Merge pull request #209 from mikey/yosys

Make yosys/nextpnr work and add to CI
jtag-port
Anton Blanchard 4 years ago committed by GitHub
commit 65fc34cf6e
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23

@ -46,3 +46,17 @@ jobs:
steps: steps:
- uses: actions/checkout@v2 - uses: actions/checkout@v2
- run: docker run -t -v $PWD:/build -w /build ghdl/vunit:llvm bash -c "make -j$(nproc) ${{ matrix.task }}" - run: docker run -t -v $PWD:/build -w /build ghdl/vunit:llvm bash -c "make -j$(nproc) ${{ matrix.task }}"

symbiflow-ecp5:
runs-on: ubuntu-latest
steps:
- uses: actions/checkout@v2
- run: make DOCKER=1 FPGA_TARGET=ECP5-EVN SYNTH_ECP5_FLAGS="-noflatten" microwatt.json
- run: make DOCKER=1 FPGA_TARGET=ECP5-EVN microwatt.bit

# test building verilog target from yosys/nextpnr
verilog:
runs-on: ubuntu-latest
steps:
- uses: actions/checkout@v2
- run: make DOCKER=1 microwatt.v

4
.gitignore vendored

@ -2,6 +2,10 @@
*~ *~
*.cf *.cf
*.s *.s
*.bit
*_out.config
microwatt.json
microwatt.svf
*_tb *_tb
main_ram.bin main_ram.bin
tests/*/*.bin tests/*/*.bin

@ -54,6 +54,7 @@ soc_files = $(core_files) wishbone_arbiter.vhdl wishbone_bram_wrapper.vhdl sync_
wishbone_debug_master.vhdl xics.vhdl syscon.vhdl soc.vhdl \ wishbone_debug_master.vhdl xics.vhdl syscon.vhdl soc.vhdl \
spi_rxtx.vhdl spi_flash_ctrl.vhdl spi_rxtx.vhdl spi_flash_ctrl.vhdl


uart_files = $(wildcard uart16550/*.v)


soc_sim_files = $(soc_files) sim_console.vhdl sim_pp_uart.vhdl sim_bram_helpers.vhdl \ soc_sim_files = $(soc_files) sim_console.vhdl sim_pp_uart.vhdl sim_bram_helpers.vhdl \
sim_bram.vhdl sim_jtag_socket.vhdl sim_jtag.vhdl dmi_dtm_xilinx.vhdl \ sim_bram.vhdl sim_jtag_socket.vhdl sim_jtag.vhdl dmi_dtm_xilinx.vhdl \
@ -142,7 +143,10 @@ RAM_INIT_FILE=hello_world/hello_world.hex
#MEMORY_SIZE=393216 #MEMORY_SIZE=393216
#RAM_INIT_FILE=micropython/firmware.hex #RAM_INIT_FILE=micropython/firmware.hex


FPGA_TARGET ?= ORANGE-CRAB

# OrangeCrab with ECP85 # OrangeCrab with ECP85
ifeq ($(FPGA_TARGET), ORANGE-CRAB)
RESET_LOW=true RESET_LOW=true
CLK_INPUT=50000000 CLK_INPUT=50000000
CLK_FREQUENCY=50000000 CLK_FREQUENCY=50000000
@ -151,16 +155,19 @@ PACKAGE=CSFBGA285
NEXTPNR_FLAGS=--um5g-85k --freq 50 NEXTPNR_FLAGS=--um5g-85k --freq 50
OPENOCD_JTAG_CONFIG=openocd/olimex-arm-usb-tiny-h.cfg OPENOCD_JTAG_CONFIG=openocd/olimex-arm-usb-tiny-h.cfg
OPENOCD_DEVICE_CONFIG=openocd/LFE5UM5G-85F.cfg OPENOCD_DEVICE_CONFIG=openocd/LFE5UM5G-85F.cfg
endif


# ECP5-EVN # ECP5-EVN
#RESET_LOW=true ifeq ($(FPGA_TARGET), ECP5-EVN)
#CLK_INPUT=12000000 RESET_LOW=true
#CLK_FREQUENCY=12000000 CLK_INPUT=12000000
#LPF=constraints/ecp5-evn.lpf CLK_FREQUENCY=12000000
#PACKAGE=CABGA381 LPF=constraints/ecp5-evn.lpf
#NEXTPNR_FLAGS=--um5g-85k --freq 12 PACKAGE=CABGA381
#OPENOCD_JTAG_CONFIG=openocd/ecp5-evn.cfg NEXTPNR_FLAGS=--um5g-85k --freq 12
#OPENOCD_DEVICE_CONFIG=openocd/LFE5UM5G-85F.cfg OPENOCD_JTAG_CONFIG=openocd/ecp5-evn.cfg
OPENOCD_DEVICE_CONFIG=openocd/LFE5UM5G-85F.cfg
endif


GHDL_IMAGE_GENERICS=-gMEMORY_SIZE=$(MEMORY_SIZE) -gRAM_INIT_FILE=$(RAM_INIT_FILE) \ GHDL_IMAGE_GENERICS=-gMEMORY_SIZE=$(MEMORY_SIZE) -gRAM_INIT_FILE=$(RAM_INIT_FILE) \
-gRESET_LOW=$(RESET_LOW) -gCLK_INPUT=$(CLK_INPUT) -gCLK_FREQUENCY=$(CLK_FREQUENCY) -gRESET_LOW=$(RESET_LOW) -gCLK_INPUT=$(CLK_INPUT) -gCLK_FREQUENCY=$(CLK_FREQUENCY)
@ -174,11 +181,11 @@ fpga_files = $(core_files) $(soc_files) fpga/soc_reset.vhdl \


synth_files = $(core_files) $(soc_files) $(fpga_files) $(clkgen) $(toplevel) $(dmi_dtm) synth_files = $(core_files) $(soc_files) $(fpga_files) $(clkgen) $(toplevel) $(dmi_dtm)


microwatt.json: $(synth_files) microwatt.json: $(synth_files) $(RAM_INIT_FILE)
$(YOSYS) -m $(GHDLSYNTH) -p "ghdl --std=08 $(GHDL_IMAGE_GENERICS) $(GHDL_TARGET_GENERICS) $(synth_files) -e toplevel; synth_ecp5 -json $@" $(YOSYS) -m $(GHDLSYNTH) -p "ghdl --std=08 --no-formal $(GHDL_IMAGE_GENERICS) $(GHDL_TARGET_GENERICS) $(synth_files) -e toplevel; synth_ecp5 -json $@ $(SYNTH_ECP5_FLAGS)" $(uart_files)


microwatt.v: $(synth_files) microwatt.v: $(synth_files) $(RAM_INIT_FILE)
$(YOSYS) -m $(GHDLSYNTH) -p "ghdl --std=08 $(GHDL_IMAGE_GENERICS) $(GHDL_TARGET_GENERICS) $(synth_files) -e toplevel; write_verilog $@" $(YOSYS) -m $(GHDLSYNTH) -p "ghdl --std=08 --no-formal $(GHDL_IMAGE_GENERICS) $(GHDL_TARGET_GENERICS) $(synth_files) -e toplevel; write_verilog $@" $(uart_files)


# Need to investigate why yosys is hitting verilator warnings, and eventually turn on -Wall # Need to investigate why yosys is hitting verilator warnings, and eventually turn on -Wall
microwatt-verilator: microwatt.v verilator/microwatt-verilator.cpp verilator/uart-verilator.c microwatt-verilator: microwatt.v verilator/microwatt-verilator.cpp verilator/uart-verilator.c
@ -187,7 +194,8 @@ microwatt-verilator: microwatt.v verilator/microwatt-verilator.cpp verilator/uar
@cp -f obj_dir/microwatt-verilator microwatt-verilator @cp -f obj_dir/microwatt-verilator microwatt-verilator


microwatt_out.config: microwatt.json $(LPF) microwatt_out.config: microwatt.json $(LPF)
$(NEXTPNR) --json $< --lpf $(LPF) --textcfg $@ $(NEXTPNR_FLAGS) --package $(PACKAGE) $(NEXTPNR) --json $< --lpf $(LPF) --textcfg $@.tmp $(NEXTPNR_FLAGS) --package $(PACKAGE)
mv -f $@.tmp $@


microwatt.bit: microwatt_out.config microwatt.bit: microwatt_out.config
$(ECPPACK) --svf microwatt.svf $< $@ $(ECPPACK) --svf microwatt.svf $< $@

Binary file not shown.

@ -14,5 +14,7 @@ int main(void)
while (1) { while (1) {
unsigned char c = getchar(); unsigned char c = getchar();
putchar(c); putchar(c);
if (c == 13) // if CR send LF
putchar(10);
} }
} }

Binary file not shown.

@ -514,19 +514,23 @@ e8010010ebc1fff0
7c0803a6ebe1fff8 7c0803a6ebe1fff8
3c4000014e800020 3c4000014e800020
7c0802a63842a000 7c0802a63842a000
f821ffe1f8010010 f8010010fbe1fff8
60000000480001dd 480001f5f821ffd1
386373a83c62ffff 3c62ffff60000000
6000000048000141 4800015d386373c0
600000004800002d 4800004960000000
480000a95463063e 7c7f1b7860000000
4bffffec60000000 57ff063e5463063e
60000000480000bd
4082ffe02c1f000d
480000a93860000a
4bffffd060000000
0100000000000000 0100000000000000
3c40000100000080 3c40000100000180
600000003842a000 600000003842a000
6000000039228000 6000000039228000
8929000039428008 8929000039428008
419e00302f890000 418200302c090000
39290014e92a0000 39290014e92a0000
7d204eaa7c0004ac 7d204eaa7c0004ac
4182ffec71290001 4182ffec71290001
@ -543,7 +547,7 @@ e86a00004082ffec
600000003842a000 600000003842a000
6000000039228000 6000000039228000
8929000039428008 8929000039428008
419e002c2f890000 4182002c2c090000
39290014e92a0000 39290014e92a0000
7d204eaa7c0004ac 7d204eaa7c0004ac
4182ffec71290020 4182ffec71290020
@ -557,48 +561,47 @@ e94a00005469063e
000000004e800020 000000004e800020
0000000000000000 0000000000000000
3842a0003c400001 3842a0003c400001
fbc1fff07c0802a6 fbe1fff87c0802a6
3bc3fffffbe1fff8 3be3fffffbc1fff0
f821ffd1f8010010 f821ffd1f8010010
2fbf00008ffe0001 2c3e00008fdf0001
38210030409e0010 3821003040820010
4bfffe5c38600000 4bfffe3c38600000
409e000c2b9f000a 4082000c281e000a
4bffff413860000d 4bffff413860000d
4bffff397fe3fb78 4bffff397fc3f378
000000004bffffd0 000000004bffffd0
0000028001000000 0000028001000000
7d4348ae39200000 386000007c6a1b78
409e000c2f8a0000 2c0900007d2a18ae
4e8000207d234b78 386300014d820020
4bffffe839290001 000000004bfffff0
0000000000000000 0000000000000000
3c40000100000000 3842a0003c400001
3d20c0003842a000 610800203d00c000
7929002061290020 7c0004ac79080020
3d20c0007d0046ea
6129000879080600
7c0004ac79290020
712900207d204eea
3d20c00041820018
7929002061290040
7d204eea7c0004ac 7d204eea7c0004ac
792906003d00c000 600000003d40c000
7908002061080008
7d0046ea7c0004ac
3940000071080020
3d40c00041820018
794a0020614a0040
7d4056ea7c0004ac
600000003d00c000
38e2800060000000 38e2800060000000
7908002061082000 794a0020614a2000
3d00001cf9028008 3d40001cf9428008
7d29439261082000 7d085392614a2000
79080fc37948f804 794a0fc3792af804
3940000141820080 3920000141820080
6108200c3d00c000 614a200c3d40c000
7908002099470000 794a002099270000
7c0004ac3940ff80 7c0004ac3920ff80
e94280087d4047aa
7d2057aa7c0004ac
7929c202e9428008
7c0004ac394a0004
e92280087d2057aa e92280087d2057aa
7d004faa7c0004ac
7908c202e9228008
7c0004ac39290004
e92280087d004faa
3929000c39400003 3929000c39400003
7d404faa7c0004ac 7d404faa7c0004ac
39290010e9228008 39290010e9228008
@ -606,26 +609,53 @@ e92280087d2057aa
39400007e9228008 39400007e9228008
7c0004ac39290008 7c0004ac39290008
4e8000207d404faa 4e8000207d404faa
990700003d40c000 994700003d20c000
614a20183929ffff 612920183908ffff
7c0004ac794a0020 7c0004ac79290020
4e8000207d2057ea 4e8000207d004fea
0000000000000000 0000000000000000
3c40000100000000 3c40000100000000
600000003842a000 600000003842a000
2ea4000039228000 2c24000039228000
2f89000089290000 2f89000089290000
e922800860000000 e922800860000000
41960024419e0030 41820024419e0030
2fa3000039400002 2c23000039400002
614a0001419e0008 614a000141820008
7c0004ac39290004 7c0004ac39290004
4e8000207d404faa 4e8000207d404faa
4bffffe039400000 4bffffe039400000
6063000241960008 6063000241820008
7c0004ac39290020 7c0004ac39290020
4e8000207c604fea 4e8000207c604fea
0000000000000000 0000000000000000
0000000000000000 0000000000000000
6f57206f6c6c6548 6f57206f6c6c6548
000000000a646c72 000000000a646c72
0000000000000010
0141780400527a01
0000001800010c1b
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300e460000000070
000000019f7e4111
0000000000000010
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0000000000000088
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0000002800000000
fffffd4c00000040
4109450000000060
300e43029e019f00
42000e0a447e4111
0000000b4106dedf
0000006c00000010
00000028fffffd80
0000001000000000
fffffd9400000080
000000000000012c
0000009400000010
00000078fffffeac
0000000000000000

@ -0,0 +1,111 @@
//////////////////////////////////////////////////////////////////////
//// ////
//// raminfr.v ////
//// ////
//// ////
//// This file is part of the "UART 16550 compatible" project ////
//// http://www.opencores.org/cores/uart16550/ ////
//// ////
//// Documentation related to this project: ////
//// - http://www.opencores.org/cores/uart16550/ ////
//// ////
//// Projects compatibility: ////
//// - WISHBONE ////
//// RS232 Protocol ////
//// 16550D uart (mostly supported) ////
//// ////
//// Overview (main Features): ////
//// Inferrable Distributed RAM for FIFOs ////
//// ////
//// Known problems (limits): ////
//// None . ////
//// ////
//// To Do: ////
//// Nothing so far. ////
//// ////
//// Author(s): ////
//// - gorban@opencores.org ////
//// - Jacob Gorban ////
//// ////
//// Created: 2002/07/22 ////
//// Last Updated: 2002/07/22 ////
//// (See log for the revision history) ////
//// ////
//// ////
//////////////////////////////////////////////////////////////////////
//// ////
//// Copyright (C) 2000, 2001 Authors ////
//// ////
//// This source file may be used and distributed without ////
//// restriction provided that this copyright statement is not ////
//// removed from the file and that any derivative work contains ////
//// the original copyright notice and the associated disclaimer. ////
//// ////
//// This source file is free software; you can redistribute it ////
//// and/or modify it under the terms of the GNU Lesser General ////
//// Public License as published by the Free Software Foundation; ////
//// either version 2.1 of the License, or (at your option) any ////
//// later version. ////
//// ////
//// This source is distributed in the hope that it will be ////
//// useful, but WITHOUT ANY WARRANTY; without even the implied ////
//// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR ////
//// PURPOSE. See the GNU Lesser General Public License for more ////
//// details. ////
//// ////
//// You should have received a copy of the GNU Lesser General ////
//// Public License along with this source; if not, download it ////
//// from http://www.opencores.org/lgpl.shtml ////
//// ////
//////////////////////////////////////////////////////////////////////
//
// CVS Revision History
//
// $Log: not supported by cvs2svn $
// Revision 1.1 2002/07/22 23:02:23 gorban
// Bug Fixes:
// * Possible loss of sync and bad reception of stop bit on slow baud rates fixed.
// Problem reported by Kenny.Tung.
// * Bad (or lack of ) loopback handling fixed. Reported by Cherry Withers.
//
// Improvements:
// * Made FIFO's as general inferrable memory where possible.
// So on FPGA they should be inferred as RAM (Distributed RAM on Xilinx).
// This saves about 1/3 of the Slice count and reduces P&R and synthesis times.
//
// * Added optional baudrate output (baud_o).
// This is identical to BAUDOUT* signal on 16550 chip.
// It outputs 16xbit_clock_rate - the divided clock.
// It's disabled by default. Define UART_HAS_BAUDRATE_OUTPUT to use.
//

//Following is the Verilog code for a dual-port RAM with asynchronous read.
module raminfr
(clk, we, a, dpra, di, dpo);

parameter addr_width = 4;
parameter data_width = 8;
parameter depth = 16;

input clk;
input we;
input [addr_width-1:0] a;
input [addr_width-1:0] dpra;
input [data_width-1:0] di;
//output [data_width-1:0] spo;
output [data_width-1:0] dpo;
reg [data_width-1:0] ram [depth-1:0];

wire [data_width-1:0] dpo;
wire [data_width-1:0] di;
wire [addr_width-1:0] a;
wire [addr_width-1:0] dpra;
always @(posedge clk) begin
if (we)
ram[a] <= di;
end
// assign spo = ram[a];
assign dpo = ram[dpra];
endmodule

@ -0,0 +1,233 @@
//////////////////////////////////////////////////////////////////////
//// ////
//// uart_defines.v ////
//// ////
//// ////
//// This file is part of the "UART 16550 compatible" project ////
//// http://www.opencores.org/cores/uart16550/ ////
//// ////
//// Documentation related to this project: ////
//// - http://www.opencores.org/cores/uart16550/ ////
//// ////
//// Projects compatibility: ////
//// - WISHBONE ////
//// RS232 Protocol ////
//// 16550D uart (mostly supported) ////
//// ////
//// Overview (main Features): ////
//// Defines of the Core ////
//// ////
//// Known problems (limits): ////
//// None ////
//// ////
//// To Do: ////
//// Nothing. ////
//// ////
//// Author(s): ////
//// - gorban@opencores.org ////
//// - Jacob Gorban ////
//// - Igor Mohor (igorm@opencores.org) ////
//// ////
//// Created: 2001/05/12 ////
//// Last Updated: 2001/05/17 ////
//// (See log for the revision history) ////
//// ////
//// ////
//////////////////////////////////////////////////////////////////////
//// ////
//// Copyright (C) 2000, 2001 Authors ////
//// ////
//// This source file may be used and distributed without ////
//// restriction provided that this copyright statement is not ////
//// removed from the file and that any derivative work contains ////
//// the original copyright notice and the associated disclaimer. ////
//// ////
//// This source file is free software; you can redistribute it ////
//// and/or modify it under the terms of the GNU Lesser General ////
//// Public License as published by the Free Software Foundation; ////
//// either version 2.1 of the License, or (at your option) any ////
//// later version. ////
//// ////
//// This source is distributed in the hope that it will be ////
//// useful, but WITHOUT ANY WARRANTY; without even the implied ////
//// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR ////
//// PURPOSE. See the GNU Lesser General Public License for more ////
//// details. ////
//// ////
//// You should have received a copy of the GNU Lesser General ////
//// Public License along with this source; if not, download it ////
//// from http://www.opencores.org/lgpl.shtml ////
//// ////
//////////////////////////////////////////////////////////////////////
//
// CVS Revision History
//
// $Log: not supported by cvs2svn $
// Revision 1.13 2003/06/11 16:37:47 gorban
// This fixes errors in some cases when data is being read and put to the FIFO at the same time. Patch is submitted by Scott Furman. Update is very recommended.
//
// Revision 1.12 2002/07/22 23:02:23 gorban
// Bug Fixes:
// * Possible loss of sync and bad reception of stop bit on slow baud rates fixed.
// Problem reported by Kenny.Tung.
// * Bad (or lack of ) loopback handling fixed. Reported by Cherry Withers.
//
// Improvements:
// * Made FIFO's as general inferrable memory where possible.
// So on FPGA they should be inferred as RAM (Distributed RAM on Xilinx).
// This saves about 1/3 of the Slice count and reduces P&R and synthesis times.
//
// * Added optional baudrate output (baud_o).
// This is identical to BAUDOUT* signal on 16550 chip.
// It outputs 16xbit_clock_rate - the divided clock.
// It's disabled by default. Define UART_HAS_BAUDRATE_OUTPUT to use.
//
// Revision 1.10 2001/12/11 08:55:40 mohor
// Scratch register define added.
//
// Revision 1.9 2001/12/03 21:44:29 gorban
// Updated specification documentation.
// Added full 32-bit data bus interface, now as default.
// Address is 5-bit wide in 32-bit data bus mode.
// Added wb_sel_i input to the core. It's used in the 32-bit mode.
// Added debug interface with two 32-bit read-only registers in 32-bit mode.
// Bits 5 and 6 of LSR are now only cleared on TX FIFO write.
// My small test bench is modified to work with 32-bit mode.
//
// Revision 1.8 2001/11/26 21:38:54 gorban
// Lots of fixes:
// Break condition wasn't handled correctly at all.
// LSR bits could lose their values.
// LSR value after reset was wrong.
// Timing of THRE interrupt signal corrected.
// LSR bit 0 timing corrected.
//
// Revision 1.7 2001/08/24 21:01:12 mohor
// Things connected to parity changed.
// Clock devider changed.
//
// Revision 1.6 2001/08/23 16:05:05 mohor
// Stop bit bug fixed.
// Parity bug fixed.
// WISHBONE read cycle bug fixed,
// OE indicator (Overrun Error) bug fixed.
// PE indicator (Parity Error) bug fixed.
// Register read bug fixed.
//
// Revision 1.5 2001/05/31 20:08:01 gorban
// FIFO changes and other corrections.
//
// Revision 1.4 2001/05/21 19:12:02 gorban
// Corrected some Linter messages.
//
// Revision 1.3 2001/05/17 18:34:18 gorban
// First 'stable' release. Should be sythesizable now. Also added new header.
//
// Revision 1.0 2001-05-17 21:27:11+02 jacob
// Initial revision
//
//

// Uncomment this if you want your UART to have
// 16xBaudrate output port.
// If defined, the enable signal will be used to drive baudrate_o signal
// It's frequency is 16xbaudrate

// `define UART_HAS_BAUDRATE_OUTPUT

// Register addresses
`define UART_REG_RB 3'd0 // receiver buffer
`define UART_REG_TR 3'd0 // transmitter
`define UART_REG_IE 3'd1 // Interrupt enable
`define UART_REG_II 3'd2 // Interrupt identification
`define UART_REG_FC 3'd2 // FIFO control
`define UART_REG_LC 3'd3 // Line Control
`define UART_REG_MC 3'd4 // Modem control
`define UART_REG_LS 3'd5 // Line status
`define UART_REG_MS 3'd6 // Modem status
`define UART_REG_SR 3'd7 // Scratch register
`define UART_REG_DL1 3'd0 // Divisor latch bytes (1-2)
`define UART_REG_DL2 3'd1

// Interrupt Enable register bits
`define UART_IE_RDA 0 // Received Data available interrupt
`define UART_IE_THRE 1 // Transmitter Holding Register empty interrupt
`define UART_IE_RLS 2 // Receiver Line Status Interrupt
`define UART_IE_MS 3 // Modem Status Interrupt

// Interrupt Identification register bits
`define UART_II_IP 0 // Interrupt pending when 0
`define UART_II_II 3:1 // Interrupt identification

// Interrupt identification values for bits 3:1
`define UART_II_RLS 3'b011 // Receiver Line Status
`define UART_II_RDA 3'b010 // Receiver Data available
`define UART_II_TI 3'b110 // Timeout Indication
`define UART_II_THRE 3'b001 // Transmitter Holding Register empty
`define UART_II_MS 3'b000 // Modem Status

// FIFO Control Register bits
`define UART_FC_TL 1:0 // Trigger level

// FIFO trigger level values
`define UART_FC_1 2'b00
`define UART_FC_4 2'b01
`define UART_FC_8 2'b10
`define UART_FC_14 2'b11

// Line Control register bits
`define UART_LC_BITS 1:0 // bits in character
`define UART_LC_SB 2 // stop bits
`define UART_LC_PE 3 // parity enable
`define UART_LC_EP 4 // even parity
`define UART_LC_SP 5 // stick parity
`define UART_LC_BC 6 // Break control
`define UART_LC_DL 7 // Divisor Latch access bit

// Modem Control register bits
`define UART_MC_DTR 0
`define UART_MC_RTS 1
`define UART_MC_OUT1 2
`define UART_MC_OUT2 3
`define UART_MC_LB 4 // Loopback mode

// Line Status Register bits
`define UART_LS_DR 0 // Data ready
`define UART_LS_OE 1 // Overrun Error
`define UART_LS_PE 2 // Parity Error
`define UART_LS_FE 3 // Framing Error
`define UART_LS_BI 4 // Break interrupt
`define UART_LS_TFE 5 // Transmit FIFO is empty
`define UART_LS_TE 6 // Transmitter Empty indicator
`define UART_LS_EI 7 // Error indicator

// Modem Status Register bits
`define UART_MS_DCTS 0 // Delta signals
`define UART_MS_DDSR 1
`define UART_MS_TERI 2
`define UART_MS_DDCD 3
`define UART_MS_CCTS 4 // Complement signals
`define UART_MS_CDSR 5
`define UART_MS_CRI 6
`define UART_MS_CDCD 7

// FIFO parameter defines

`define UART_FIFO_WIDTH 8
`define UART_FIFO_DEPTH 16
`define UART_FIFO_POINTER_W 4
`define UART_FIFO_COUNTER_W 5
// receiver fifo has width 11 because it has break, parity and framing error bits
`define UART_FIFO_REC_WIDTH 11


`define VERBOSE_WB 0 // All activity on the WISHBONE is recorded
`define VERBOSE_LINE_STATUS 0 // Details about the lsr (line status register)
`define FAST_TEST 1 // 64/1024 packets are sent







@ -0,0 +1,475 @@
//////////////////////////////////////////////////////////////////////
//// ////
//// uart_receiver.v ////
//// ////
//// ////
//// This file is part of the "UART 16550 compatible" project ////
//// http://www.opencores.org/cores/uart16550/ ////
//// ////
//// Documentation related to this project: ////
//// - http://www.opencores.org/cores/uart16550/ ////
//// ////
//// Projects compatibility: ////
//// - WISHBONE ////
//// RS232 Protocol ////
//// 16550D uart (mostly supported) ////
//// ////
//// Overview (main Features): ////
//// UART core receiver logic ////
//// ////
//// Known problems (limits): ////
//// None known ////
//// ////
//// To Do: ////
//// Thourough testing. ////
//// ////
//// Author(s): ////
//// - gorban@opencores.org ////
//// - Jacob Gorban ////
//// - Igor Mohor (igorm@opencores.org) ////
//// ////
//// Created: 2001/05/12 ////
//// Last Updated: 2001/05/17 ////
//// (See log for the revision history) ////
//// ////
//// ////
//////////////////////////////////////////////////////////////////////
//// ////
//// Copyright (C) 2000, 2001 Authors ////
//// ////
//// This source file may be used and distributed without ////
//// restriction provided that this copyright statement is not ////
//// removed from the file and that any derivative work contains ////
//// the original copyright notice and the associated disclaimer. ////
//// ////
//// This source file is free software; you can redistribute it ////
//// and/or modify it under the terms of the GNU Lesser General ////
//// Public License as published by the Free Software Foundation; ////
//// either version 2.1 of the License, or (at your option) any ////
//// later version. ////
//// ////
//// This source is distributed in the hope that it will be ////
//// useful, but WITHOUT ANY WARRANTY; without even the implied ////
//// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR ////
//// PURPOSE. See the GNU Lesser General Public License for more ////
//// details. ////
//// ////
//// You should have received a copy of the GNU Lesser General ////
//// Public License along with this source; if not, download it ////
//// from http://www.opencores.org/lgpl.shtml ////
//// ////
//////////////////////////////////////////////////////////////////////
//
// CVS Revision History
//
// $Log: not supported by cvs2svn $
// Revision 1.29 2002/07/29 21:16:18 gorban
// The uart_defines.v file is included again in sources.
//
// Revision 1.28 2002/07/22 23:02:23 gorban
// Bug Fixes:
// * Possible loss of sync and bad reception of stop bit on slow baud rates fixed.
// Problem reported by Kenny.Tung.
// * Bad (or lack of ) loopback handling fixed. Reported by Cherry Withers.
//
// Improvements:
// * Made FIFO's as general inferrable memory where possible.
// So on FPGA they should be inferred as RAM (Distributed RAM on Xilinx).
// This saves about 1/3 of the Slice count and reduces P&R and synthesis times.
//
// * Added optional baudrate output (baud_o).
// This is identical to BAUDOUT* signal on 16550 chip.
// It outputs 16xbit_clock_rate - the divided clock.
// It's disabled by default. Define UART_HAS_BAUDRATE_OUTPUT to use.
//
// Revision 1.27 2001/12/30 20:39:13 mohor
// More than one character was stored in case of break. End of the break
// was not detected correctly.
//
// Revision 1.26 2001/12/20 13:28:27 mohor
// Missing declaration of rf_push_q fixed.
//
// Revision 1.25 2001/12/20 13:25:46 mohor
// rx push changed to be only one cycle wide.
//
// Revision 1.24 2001/12/19 08:03:34 mohor
// Warnings cleared.
//
// Revision 1.23 2001/12/19 07:33:54 mohor
// Synplicity was having troubles with the comment.
//
// Revision 1.22 2001/12/17 14:46:48 mohor
// overrun signal was moved to separate block because many sequential lsr
// reads were preventing data from being written to rx fifo.
// underrun signal was not used and was removed from the project.
//
// Revision 1.21 2001/12/13 10:31:16 mohor
// timeout irq must be set regardless of the rda irq (rda irq does not reset the
// timeout counter).
//
// Revision 1.20 2001/12/10 19:52:05 gorban
// Igor fixed break condition bugs
//
// Revision 1.19 2001/12/06 14:51:04 gorban
// Bug in LSR[0] is fixed.
// All WISHBONE signals are now sampled, so another wait-state is introduced on all transfers.
//
// Revision 1.18 2001/12/03 21:44:29 gorban
// Updated specification documentation.
// Added full 32-bit data bus interface, now as default.
// Address is 5-bit wide in 32-bit data bus mode.
// Added wb_sel_i input to the core. It's used in the 32-bit mode.
// Added debug interface with two 32-bit read-only registers in 32-bit mode.
// Bits 5 and 6 of LSR are now only cleared on TX FIFO write.
// My small test bench is modified to work with 32-bit mode.
//
// Revision 1.17 2001/11/28 19:36:39 gorban
// Fixed: timeout and break didn't pay attention to current data format when counting time
//
// Revision 1.16 2001/11/27 22:17:09 gorban
// Fixed bug that prevented synthesis in uart_receiver.v
//
// Revision 1.15 2001/11/26 21:38:54 gorban
// Lots of fixes:
// Break condition wasn't handled correctly at all.
// LSR bits could lose their values.
// LSR value after reset was wrong.
// Timing of THRE interrupt signal corrected.
// LSR bit 0 timing corrected.
//
// Revision 1.14 2001/11/10 12:43:21 gorban
// Logic Synthesis bugs fixed. Some other minor changes
//
// Revision 1.13 2001/11/08 14:54:23 mohor
// Comments in Slovene language deleted, few small fixes for better work of
// old tools. IRQs need to be fix.
//
// Revision 1.12 2001/11/07 17:51:52 gorban
// Heavily rewritten interrupt and LSR subsystems.
// Many bugs hopefully squashed.
//
// Revision 1.11 2001/10/31 15:19:22 gorban
// Fixes to break and timeout conditions
//
// Revision 1.10 2001/10/20 09:58:40 gorban
// Small synopsis fixes
//
// Revision 1.9 2001/08/24 21:01:12 mohor
// Things connected to parity changed.
// Clock devider changed.
//
// Revision 1.8 2001/08/23 16:05:05 mohor
// Stop bit bug fixed.
// Parity bug fixed.
// WISHBONE read cycle bug fixed,
// OE indicator (Overrun Error) bug fixed.
// PE indicator (Parity Error) bug fixed.
// Register read bug fixed.
//
// Revision 1.6 2001/06/23 11:21:48 gorban
// DL made 16-bit long. Fixed transmission/reception bugs.
//
// Revision 1.5 2001/06/02 14:28:14 gorban
// Fixed receiver and transmitter. Major bug fixed.
//
// Revision 1.4 2001/05/31 20:08:01 gorban
// FIFO changes and other corrections.
//
// Revision 1.3 2001/05/27 17:37:49 gorban
// Fixed many bugs. Updated spec. Changed FIFO files structure. See CHANGES.txt file.
//
// Revision 1.2 2001/05/21 19:12:02 gorban
// Corrected some Linter messages.
//
// Revision 1.1 2001/05/17 18:34:18 gorban
// First 'stable' release. Should be sythesizable now. Also added new header.
//
// Revision 1.0 2001-05-17 21:27:11+02 jacob
// Initial revision
//
//

`include "uart_defines.v"

module uart_receiver (clk, wb_rst_i, lcr, rf_pop, srx_pad_i, enable,
counter_t, rf_count, rf_data_out, rf_error_bit, rf_overrun, rx_reset, lsr_mask, rstate, rf_push_pulse);

input clk;
input wb_rst_i;
input [7:0] lcr;
input rf_pop;
input srx_pad_i;
input enable;
input rx_reset;
input lsr_mask;

output [9:0] counter_t;
output [`UART_FIFO_COUNTER_W-1:0] rf_count;
output [`UART_FIFO_REC_WIDTH-1:0] rf_data_out;
output rf_overrun;
output rf_error_bit;
output [3:0] rstate;
output rf_push_pulse;

reg [3:0] rstate;
reg [3:0] rcounter16;
reg [2:0] rbit_counter;
reg [7:0] rshift; // receiver shift register
reg rparity; // received parity
reg rparity_error;
reg rframing_error; // framing error flag
reg rparity_xor;
reg [7:0] counter_b; // counts the 0 (low) signals
reg rf_push_q;

// RX FIFO signals
reg [`UART_FIFO_REC_WIDTH-1:0] rf_data_in;
wire [`UART_FIFO_REC_WIDTH-1:0] rf_data_out;
wire rf_push_pulse;
reg rf_push;
wire rf_pop;
wire rf_overrun;
wire [`UART_FIFO_COUNTER_W-1:0] rf_count;
wire rf_error_bit; // an error (parity or framing) is inside the fifo
wire break_error = (counter_b == 0);

// RX FIFO instance
uart_rfifo #(`UART_FIFO_REC_WIDTH) fifo_rx(
.clk( clk ),
.wb_rst_i( wb_rst_i ),
.data_in( rf_data_in ),
.data_out( rf_data_out ),
.push( rf_push_pulse ),
.pop( rf_pop ),
.overrun( rf_overrun ),
.count( rf_count ),
.error_bit( rf_error_bit ),
.fifo_reset( rx_reset ),
.reset_status(lsr_mask)
);

wire rcounter16_eq_7 = (rcounter16 == 4'd7);
wire rcounter16_eq_0 = (rcounter16 == 4'd0);

wire [3:0] rcounter16_minus_1 = rcounter16 - 3'd1;

parameter sr_idle = 4'd0;
parameter sr_rec_start = 4'd1;
parameter sr_rec_bit = 4'd2;
parameter sr_rec_parity = 4'd3;
parameter sr_rec_stop = 4'd4;
parameter sr_check_parity = 4'd5;
parameter sr_rec_prepare = 4'd6;
parameter sr_end_bit = 4'd7;
parameter sr_ca_lc_parity = 4'd8;
parameter sr_wait1 = 4'd9;
parameter sr_push = 4'd10;


always @(posedge clk or posedge wb_rst_i)
begin
if (wb_rst_i)
begin
rstate <= sr_idle;
rcounter16 <= 0;
rbit_counter <= 0;
rparity_xor <= 1'b0;
rframing_error <= 1'b0;
rparity_error <= 1'b0;
rparity <= 1'b0;
rshift <= 0;
rf_push <= 1'b0;
rf_data_in <= 0;
end
else
if (enable)
begin
case (rstate)
sr_idle : begin
rf_push <= 1'b0;
rf_data_in <= 0;
rcounter16 <= 4'b1110;
if (srx_pad_i==1'b0 & ~break_error) // detected a pulse (start bit?)
begin
rstate <= sr_rec_start;
end
end
sr_rec_start : begin
rf_push <= 1'b0;
if (rcounter16_eq_7) // check the pulse
if (srx_pad_i==1'b1) // no start bit
rstate <= sr_idle;
else // start bit detected
rstate <= sr_rec_prepare;
rcounter16 <= rcounter16_minus_1;
end
sr_rec_prepare:begin
case (lcr[/*`UART_LC_BITS*/1:0]) // number of bits in a word
2'b00 : rbit_counter <= 3'b100;
2'b01 : rbit_counter <= 3'b101;
2'b10 : rbit_counter <= 3'b110;
2'b11 : rbit_counter <= 3'b111;
endcase
if (rcounter16_eq_0)
begin
rstate <= sr_rec_bit;
rcounter16 <= 4'b1110;
rshift <= 0;
end
else
rstate <= sr_rec_prepare;
rcounter16 <= rcounter16_minus_1;
end
sr_rec_bit : begin
if (rcounter16_eq_0)
rstate <= sr_end_bit;
if (rcounter16_eq_7) // read the bit
case (lcr[/*`UART_LC_BITS*/1:0]) // number of bits in a word
2'b00 : rshift[4:0] <= {srx_pad_i, rshift[4:1]};
2'b01 : rshift[5:0] <= {srx_pad_i, rshift[5:1]};
2'b10 : rshift[6:0] <= {srx_pad_i, rshift[6:1]};
2'b11 : rshift[7:0] <= {srx_pad_i, rshift[7:1]};
endcase
rcounter16 <= rcounter16_minus_1;
end
sr_end_bit : begin
if (rbit_counter==3'b0) // no more bits in word
if (lcr[`UART_LC_PE]) // choose state based on parity
rstate <= sr_rec_parity;
else
begin
rstate <= sr_rec_stop;
rparity_error <= 1'b0; // no parity - no error :)
end
else // else we have more bits to read
begin
rstate <= sr_rec_bit;
rbit_counter <= rbit_counter - 3'd1;
end
rcounter16 <= 4'b1110;
end
sr_rec_parity: begin
if (rcounter16_eq_7) // read the parity
begin
rparity <= srx_pad_i;
rstate <= sr_ca_lc_parity;
end
rcounter16 <= rcounter16_minus_1;
end
sr_ca_lc_parity : begin // rcounter equals 6
rcounter16 <= rcounter16_minus_1;
rparity_xor <= ^{rshift,rparity}; // calculate parity on all incoming data
rstate <= sr_check_parity;
end
sr_check_parity: begin // rcounter equals 5
case ({lcr[`UART_LC_EP],lcr[`UART_LC_SP]})
2'b00: rparity_error <= rparity_xor == 0; // no error if parity 1
2'b01: rparity_error <= ~rparity; // parity should sticked to 1
2'b10: rparity_error <= rparity_xor == 1; // error if parity is odd
2'b11: rparity_error <= rparity; // parity should be sticked to 0
endcase
rcounter16 <= rcounter16_minus_1;
rstate <= sr_wait1;
end
sr_wait1 : if (rcounter16_eq_0)
begin
rstate <= sr_rec_stop;
rcounter16 <= 4'b1110;
end
else
rcounter16 <= rcounter16_minus_1;
sr_rec_stop : begin
if (rcounter16_eq_7) // read the parity
begin
rframing_error <= !srx_pad_i; // no framing error if input is 1 (stop bit)
rstate <= sr_push;
end
rcounter16 <= rcounter16_minus_1;
end
sr_push : begin
///////////////////////////////////////
// $display($time, ": received: %b", rf_data_in);
if(srx_pad_i | break_error)
begin
if(break_error)
rf_data_in <= {8'b0, 3'b100}; // break input (empty character) to receiver FIFO
else
rf_data_in <= {rshift, 1'b0, rparity_error, rframing_error};
rf_push <= 1'b1;
rstate <= sr_idle;
end
else if(~rframing_error) // There's always a framing before break_error -> wait for break or srx_pad_i
begin
rf_data_in <= {rshift, 1'b0, rparity_error, rframing_error};
rf_push <= 1'b1;
rcounter16 <= 4'b1110;
rstate <= sr_rec_start;
end
end
default : rstate <= sr_idle;
endcase
end // if (enable)
end // always of receiver

always @ (posedge clk or posedge wb_rst_i)
begin
if(wb_rst_i)
rf_push_q <= 0;
else
rf_push_q <= rf_push;
end

assign rf_push_pulse = rf_push & ~rf_push_q;

//
// Break condition detection.
// Works in conjuction with the receiver state machine

reg [9:0] toc_value; // value to be set to timeout counter

always @(lcr)
case (lcr[3:0])
4'b0000 : toc_value = 447; // 7 bits
4'b0100 : toc_value = 479; // 7.5 bits
4'b0001, 4'b1000 : toc_value = 511; // 8 bits
4'b1100 : toc_value = 543; // 8.5 bits
4'b0010, 4'b0101, 4'b1001 : toc_value = 575; // 9 bits
4'b0011, 4'b0110, 4'b1010, 4'b1101 : toc_value = 639; // 10 bits
4'b0111, 4'b1011, 4'b1110 : toc_value = 703; // 11 bits
4'b1111 : toc_value = 767; // 12 bits
endcase // case(lcr[3:0])

wire [7:0] brc_value; // value to be set to break counter
assign brc_value = toc_value[9:2]; // the same as timeout but 1 insead of 4 character times

always @(posedge clk or posedge wb_rst_i)
begin
if (wb_rst_i)
counter_b <= 8'd159;
else
if (srx_pad_i)
counter_b <= brc_value; // character time length - 1
else
if(enable & counter_b != 8'b0) // only work on enable times break not reached.
counter_b <= counter_b - 8'd1; // decrement break counter
end // always of break condition detection

///
/// Timeout condition detection
reg [9:0] counter_t; // counts the timeout condition clocks

always @(posedge clk or posedge wb_rst_i)
begin
if (wb_rst_i)
counter_t <= 10'd639; // 10 bits for the default 8N1
else
if(rf_push_pulse || rf_pop || rf_count == 0) // counter is reset when RX FIFO is empty, accessed or above trigger level
counter_t <= toc_value;
else
if (enable && counter_t != 10'b0) // we don't want to underflow
counter_t <= counter_t - 10'd1;
end
endmodule

@ -0,0 +1,888 @@
//////////////////////////////////////////////////////////////////////
//// ////
//// uart_regs.v ////
//// ////
//// ////
//// This file is part of the "UART 16550 compatible" project ////
//// http://www.opencores.org/cores/uart16550/ ////
//// ////
//// Documentation related to this project: ////
//// - http://www.opencores.org/cores/uart16550/ ////
//// ////
//// Projects compatibility: ////
//// - WISHBONE ////
//// RS232 Protocol ////
//// 16550D uart (mostly supported) ////
//// ////
//// Overview (main Features): ////
//// Registers of the uart 16550 core ////
//// ////
//// Known problems (limits): ////
//// Inserts 1 wait state in all WISHBONE transfers ////
//// ////
//// To Do: ////
//// Nothing or verification. ////
//// ////
//// Author(s): ////
//// - gorban@opencores.org ////
//// - Jacob Gorban ////
//// - Igor Mohor (igorm@opencores.org) ////
//// ////
//// Created: 2001/05/12 ////
//// Last Updated: (See log for the revision history ////
//// ////
//// ////
//////////////////////////////////////////////////////////////////////
//// ////
//// Copyright (C) 2000, 2001 Authors ////
//// ////
//// This source file may be used and distributed without ////
//// restriction provided that this copyright statement is not ////
//// removed from the file and that any derivative work contains ////
//// the original copyright notice and the associated disclaimer. ////
//// ////
//// This source file is free software; you can redistribute it ////
//// and/or modify it under the terms of the GNU Lesser General ////
//// Public License as published by the Free Software Foundation; ////
//// either version 2.1 of the License, or (at your option) any ////
//// later version. ////
//// ////
//// This source is distributed in the hope that it will be ////
//// useful, but WITHOUT ANY WARRANTY; without even the implied ////
//// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR ////
//// PURPOSE. See the GNU Lesser General Public License for more ////
//// details. ////
//// ////
//// You should have received a copy of the GNU Lesser General ////
//// Public License along with this source; if not, download it ////
//// from http://www.opencores.org/lgpl.shtml ////
//// ////
//////////////////////////////////////////////////////////////////////
//
// CVS Revision History
//
// $Log: not supported by cvs2svn $
// Revision 1.41 2004/05/21 11:44:41 tadejm
// Added synchronizer flops for RX input.
//
// Revision 1.40 2003/06/11 16:37:47 gorban
// This fixes errors in some cases when data is being read and put to the FIFO at the same time. Patch is submitted by Scott Furman. Update is very recommended.
//
// Revision 1.39 2002/07/29 21:16:18 gorban
// The uart_defines.v file is included again in sources.
//
// Revision 1.38 2002/07/22 23:02:23 gorban
// Bug Fixes:
// * Possible loss of sync and bad reception of stop bit on slow baud rates fixed.
// Problem reported by Kenny.Tung.
// * Bad (or lack of ) loopback handling fixed. Reported by Cherry Withers.
//
// Improvements:
// * Made FIFO's as general inferrable memory where possible.
// So on FPGA they should be inferred as RAM (Distributed RAM on Xilinx).
// This saves about 1/3 of the Slice count and reduces P&R and synthesis times.
//
// * Added optional baudrate output (baud_o).
// This is identical to BAUDOUT* signal on 16550 chip.
// It outputs 16xbit_clock_rate - the divided clock.
// It's disabled by default. Define UART_HAS_BAUDRATE_OUTPUT to use.
//
// Revision 1.37 2001/12/27 13:24:09 mohor
// lsr[7] was not showing overrun errors.
//
// Revision 1.36 2001/12/20 13:25:46 mohor
// rx push changed to be only one cycle wide.
//
// Revision 1.35 2001/12/19 08:03:34 mohor
// Warnings cleared.
//
// Revision 1.34 2001/12/19 07:33:54 mohor
// Synplicity was having troubles with the comment.
//
// Revision 1.33 2001/12/17 10:14:43 mohor
// Things related to msr register changed. After THRE IRQ occurs, and one
// character is written to the transmit fifo, the detection of the THRE bit in the
// LSR is delayed for one character time.
//
// Revision 1.32 2001/12/14 13:19:24 mohor
// MSR register fixed.
//
// Revision 1.31 2001/12/14 10:06:58 mohor
// After reset modem status register MSR should be reset.
//
// Revision 1.30 2001/12/13 10:09:13 mohor
// thre irq should be cleared only when being source of interrupt.
//
// Revision 1.29 2001/12/12 09:05:46 mohor
// LSR status bit 0 was not cleared correctly in case of reseting the FCR (rx fifo).
//
// Revision 1.28 2001/12/10 19:52:41 gorban
// Scratch register added
//
// Revision 1.27 2001/12/06 14:51:04 gorban
// Bug in LSR[0] is fixed.
// All WISHBONE signals are now sampled, so another wait-state is introduced on all transfers.
//
// Revision 1.26 2001/12/03 21:44:29 gorban
// Updated specification documentation.
// Added full 32-bit data bus interface, now as default.
// Address is 5-bit wide in 32-bit data bus mode.
// Added wb_sel_i input to the core. It's used in the 32-bit mode.
// Added debug interface with two 32-bit read-only registers in 32-bit mode.
// Bits 5 and 6 of LSR are now only cleared on TX FIFO write.
// My small test bench is modified to work with 32-bit mode.
//
// Revision 1.25 2001/11/28 19:36:39 gorban
// Fixed: timeout and break didn't pay attention to current data format when counting time
//
// Revision 1.24 2001/11/26 21:38:54 gorban
// Lots of fixes:
// Break condition wasn't handled correctly at all.
// LSR bits could lose their values.
// LSR value after reset was wrong.
// Timing of THRE interrupt signal corrected.
// LSR bit 0 timing corrected.
//
// Revision 1.23 2001/11/12 21:57:29 gorban
// fixed more typo bugs
//
// Revision 1.22 2001/11/12 15:02:28 mohor
// lsr1r error fixed.
//
// Revision 1.21 2001/11/12 14:57:27 mohor
// ti_int_pnd error fixed.
//
// Revision 1.20 2001/11/12 14:50:27 mohor
// ti_int_d error fixed.
//
// Revision 1.19 2001/11/10 12:43:21 gorban
// Logic Synthesis bugs fixed. Some other minor changes
//
// Revision 1.18 2001/11/08 14:54:23 mohor
// Comments in Slovene language deleted, few small fixes for better work of
// old tools. IRQs need to be fix.
//
// Revision 1.17 2001/11/07 17:51:52 gorban
// Heavily rewritten interrupt and LSR subsystems.
// Many bugs hopefully squashed.
//
// Revision 1.16 2001/11/02 09:55:16 mohor
// no message
//
// Revision 1.15 2001/10/31 15:19:22 gorban
// Fixes to break and timeout conditions
//
// Revision 1.14 2001/10/29 17:00:46 gorban
// fixed parity sending and tx_fifo resets over- and underrun
//
// Revision 1.13 2001/10/20 09:58:40 gorban
// Small synopsis fixes
//
// Revision 1.12 2001/10/19 16:21:40 gorban
// Changes data_out to be synchronous again as it should have been.
//
// Revision 1.11 2001/10/18 20:35:45 gorban
// small fix
//
// Revision 1.10 2001/08/24 21:01:12 mohor
// Things connected to parity changed.
// Clock devider changed.
//
// Revision 1.9 2001/08/23 16:05:05 mohor
// Stop bit bug fixed.
// Parity bug fixed.
// WISHBONE read cycle bug fixed,
// OE indicator (Overrun Error) bug fixed.
// PE indicator (Parity Error) bug fixed.
// Register read bug fixed.
//
// Revision 1.10 2001/06/23 11:21:48 gorban
// DL made 16-bit long. Fixed transmission/reception bugs.
//
// Revision 1.9 2001/05/31 20:08:01 gorban
// FIFO changes and other corrections.
//
// Revision 1.8 2001/05/29 20:05:04 gorban
// Fixed some bugs and synthesis problems.
//
// Revision 1.7 2001/05/27 17:37:49 gorban
// Fixed many bugs. Updated spec. Changed FIFO files structure. See CHANGES.txt file.
//
// Revision 1.6 2001/05/21 19:12:02 gorban
// Corrected some Linter messages.
//
// Revision 1.5 2001/05/17 18:34:18 gorban
// First 'stable' release. Should be sythesizable now. Also added new header.
//
// Revision 1.0 2001-05-17 21:27:11+02 jacob
// Initial revision
//
//

`include "uart_defines.v"

`define UART_DL1 7:0
`define UART_DL2 15:8

module uart_regs
#(parameter SIM = 0)
(clk,
wb_rst_i, wb_addr_i, wb_dat_i, wb_dat_o, wb_we_i, wb_re_i,

// additional signals
modem_inputs,
stx_pad_o, srx_pad_i,

rts_pad_o, dtr_pad_o, int_o
`ifdef UART_HAS_BAUDRATE_OUTPUT
, baud_o
`endif

);

input clk;
input wb_rst_i;
input [2:0] wb_addr_i;
input [7:0] wb_dat_i;
output [7:0] wb_dat_o;
input wb_we_i;
input wb_re_i;

output stx_pad_o;
input srx_pad_i;

input [3:0] modem_inputs;
output rts_pad_o;
output dtr_pad_o;
output int_o;
`ifdef UART_HAS_BAUDRATE_OUTPUT
output baud_o;
`endif

wire [3:0] modem_inputs;
reg enable;
`ifdef UART_HAS_BAUDRATE_OUTPUT
assign baud_o = enable; // baud_o is actually the enable signal
`endif


wire stx_pad_o; // received from transmitter module
wire srx_pad_i;
wire srx_pad;

reg [7:0] wb_dat_o;

wire [2:0] wb_addr_i;
wire [7:0] wb_dat_i;


reg [3:0] ier;
reg [3:0] iir;
reg [1:0] fcr; /// bits 7 and 6 of fcr. Other bits are ignored
reg [4:0] mcr;
reg [7:0] lcr;
reg [7:0] msr;
reg [15:0] dl; // 32-bit divisor latch
reg [7:0] scratch; // UART scratch register
reg start_dlc; // activate dlc on writing to UART_DL1
reg lsr_mask_d; // delay for lsr_mask condition
reg msi_reset; // reset MSR 4 lower bits indicator
//reg threi_clear; // THRE interrupt clear flag
reg [15:0] dlc; // 32-bit divisor latch counter
reg int_o;

reg [3:0] trigger_level; // trigger level of the receiver FIFO
reg rx_reset;
reg tx_reset;

wire dlab; // divisor latch access bit
wire cts_pad_i, dsr_pad_i, ri_pad_i, dcd_pad_i; // modem status bits
wire loopback; // loopback bit (MCR bit 4)
wire cts, dsr, ri, dcd; // effective signals
wire cts_c, dsr_c, ri_c, dcd_c; // Complement effective signals (considering loopback)
wire rts_pad_o, dtr_pad_o; // modem control outputs

// LSR bits wires and regs
wire [7:0] lsr;
wire lsr0, lsr1, lsr2, lsr3, lsr4, lsr5, lsr6, lsr7;
reg lsr0r, lsr1r, lsr2r, lsr3r, lsr4r, lsr5r, lsr6r, lsr7r;
wire lsr_mask; // lsr_mask

//
// ASSINGS
//

assign lsr[7:0] = { lsr7r, lsr6r, lsr5r, lsr4r, lsr3r, lsr2r, lsr1r, lsr0r };

assign {cts_pad_i, dsr_pad_i, ri_pad_i, dcd_pad_i} = modem_inputs;
assign {cts, dsr, ri, dcd} = ~{cts_pad_i,dsr_pad_i,ri_pad_i,dcd_pad_i};

assign {cts_c, dsr_c, ri_c, dcd_c} = loopback ? {mcr[`UART_MC_RTS],mcr[`UART_MC_DTR],mcr[`UART_MC_OUT1],mcr[`UART_MC_OUT2]}
: {cts_pad_i,dsr_pad_i,ri_pad_i,dcd_pad_i};

assign dlab = lcr[`UART_LC_DL];
assign loopback = mcr[4];

// assign modem outputs
assign rts_pad_o = mcr[`UART_MC_RTS];
assign dtr_pad_o = mcr[`UART_MC_DTR];

// Interrupt signals
wire rls_int; // receiver line status interrupt
wire rda_int; // receiver data available interrupt
wire ti_int; // timeout indicator interrupt
wire thre_int; // transmitter holding register empty interrupt
wire ms_int; // modem status interrupt

// FIFO signals
reg tf_push;
reg rf_pop;
wire [`UART_FIFO_REC_WIDTH-1:0] rf_data_out;
wire rf_error_bit; // an error (parity or framing) is inside the fifo
wire rf_overrun;
wire rf_push_pulse;
wire [`UART_FIFO_COUNTER_W-1:0] rf_count;
wire [`UART_FIFO_COUNTER_W-1:0] tf_count;
wire [2:0] tstate;
wire [3:0] rstate;
wire [9:0] counter_t;

wire thre_set_en; // THRE status is delayed one character time when a character is written to fifo.
reg [7:0] block_cnt; // While counter counts, THRE status is blocked (delayed one character cycle)
reg [7:0] block_value; // One character length minus stop bit

// Transmitter Instance
wire serial_out;

uart_transmitter #(.SIM (SIM)) transmitter(clk, wb_rst_i, lcr, tf_push, wb_dat_i, enable, serial_out, tstate, tf_count, tx_reset, lsr_mask);

// Synchronizing and sampling serial RX input
uart_sync_flops i_uart_sync_flops
(
.rst_i (wb_rst_i),
.clk_i (clk),
.stage1_rst_i (1'b0),
.stage1_clk_en_i (1'b1),
.async_dat_i (srx_pad_i),
.sync_dat_o (srx_pad)
);
defparam i_uart_sync_flops.width = 1;
defparam i_uart_sync_flops.init_value = 1'b1;

// handle loopback
wire serial_in = loopback ? serial_out : srx_pad;
assign stx_pad_o = loopback ? 1'b1 : serial_out;

// Receiver Instance
uart_receiver receiver(clk, wb_rst_i, lcr, rf_pop, serial_in, enable,
counter_t, rf_count, rf_data_out, rf_error_bit, rf_overrun, rx_reset, lsr_mask, rstate, rf_push_pulse);


// Asynchronous reading here because the outputs are sampled in uart_wb.v file
always @(dl or dlab or ier or iir or scratch
or lcr or lsr or msr or rf_data_out or wb_addr_i or wb_re_i) // asynchrounous reading
begin
case (wb_addr_i)
`UART_REG_RB : wb_dat_o = dlab ? dl[`UART_DL1] : rf_data_out[10:3];
`UART_REG_IE : wb_dat_o = dlab ? dl[`UART_DL2] : {4'd0,ier};
`UART_REG_II : wb_dat_o = {4'b1100,iir};
`UART_REG_LC : wb_dat_o = lcr;
`UART_REG_LS : wb_dat_o = lsr;
`UART_REG_MS : wb_dat_o = msr;
`UART_REG_SR : wb_dat_o = scratch;
default: wb_dat_o = 8'b0; // ??
endcase // case(wb_addr_i)
end // always @ (dl or dlab or ier or iir or scratch...


// rf_pop signal handling
always @(posedge clk or posedge wb_rst_i)
begin
if (wb_rst_i)
rf_pop <= 0;
else
if (rf_pop) // restore the signal to 0 after one clock cycle
rf_pop <= 0;
else
if (wb_re_i && wb_addr_i == `UART_REG_RB && !dlab)
rf_pop <= 1; // advance read pointer
end

wire lsr_mask_condition;
wire iir_read;
wire msr_read;
wire fifo_read;
wire fifo_write;

assign lsr_mask_condition = (wb_re_i && wb_addr_i == `UART_REG_LS && !dlab);
assign iir_read = (wb_re_i && wb_addr_i == `UART_REG_II && !dlab);
assign msr_read = (wb_re_i && wb_addr_i == `UART_REG_MS && !dlab);
assign fifo_read = (wb_re_i && wb_addr_i == `UART_REG_RB && !dlab);
assign fifo_write = (wb_we_i && wb_addr_i == `UART_REG_TR && !dlab);

// lsr_mask_d delayed signal handling
always @(posedge clk or posedge wb_rst_i)
begin
if (wb_rst_i)
lsr_mask_d <= 0;
else // reset bits in the Line Status Register
lsr_mask_d <= lsr_mask_condition;
end

// lsr_mask is rise detected
assign lsr_mask = lsr_mask_condition && ~lsr_mask_d;

// msi_reset signal handling
always @(posedge clk or posedge wb_rst_i)
begin
if (wb_rst_i)
msi_reset <= 1;
else
if (msi_reset)
msi_reset <= 0;
else
if (msr_read)
msi_reset <= 1; // reset bits in Modem Status Register
end


//
// WRITES AND RESETS //
//
// Line Control Register
always @(posedge clk or posedge wb_rst_i)
if (wb_rst_i)
lcr <= 8'b00000011; // 8n1 setting
else
if (wb_we_i && wb_addr_i==`UART_REG_LC)
lcr <= wb_dat_i;

// Interrupt Enable Register or UART_DL2
always @(posedge clk or posedge wb_rst_i)
if (wb_rst_i)
begin
ier <= 4'b0000; // no interrupts after reset
`ifdef PRESCALER_PRESET_HARD
dl[`UART_DL2] <= `PRESCALER_HIGH_PRESET;
`else
dl[`UART_DL2] <= 8'b0;
`endif
end
else
if (wb_we_i && wb_addr_i==`UART_REG_IE)
if (dlab)
begin
dl[`UART_DL2] <=
`ifdef PRESCALER_PRESET_HARD
dl[`UART_DL2];
`else
wb_dat_i;
`endif
end
else
ier <= wb_dat_i[3:0]; // ier uses only 4 lsb


// FIFO Control Register and rx_reset, tx_reset signals
always @(posedge clk or posedge wb_rst_i)
if (wb_rst_i) begin
fcr <= 2'b11;
rx_reset <= 0;
tx_reset <= 0;
end else
if (wb_we_i && wb_addr_i==`UART_REG_FC) begin
fcr <= wb_dat_i[7:6];
rx_reset <= wb_dat_i[1];
tx_reset <= wb_dat_i[2];
end else begin
rx_reset <= 0;
tx_reset <= 0;
end

// Modem Control Register
always @(posedge clk or posedge wb_rst_i)
if (wb_rst_i)
mcr <= 5'b0;
else
if (wb_we_i && wb_addr_i==`UART_REG_MC)
mcr <= wb_dat_i[4:0];

// Scratch register
// Line Control Register
always @(posedge clk or posedge wb_rst_i)
if (wb_rst_i)
scratch <= 0; // 8n1 setting
else
if (wb_we_i && wb_addr_i==`UART_REG_SR)
scratch <= wb_dat_i;

// TX_FIFO or UART_DL1
always @(posedge clk or posedge wb_rst_i)
if (wb_rst_i)
begin
`ifdef PRESCALER_PRESET_HARD
dl[`UART_DL1] <= `PRESCALER_LOW_PRESET;
`else
dl[`UART_DL1] <= 8'b0;
`endif
tf_push <= 1'b0;
start_dlc <= 1'b0;
end
else
if (wb_we_i && wb_addr_i==`UART_REG_TR)
if (dlab)
begin
`ifdef PRESCALER_PRESET_HARD
dl[`UART_DL1] <= dl[`UART_DL1];
`else
dl[`UART_DL1] <= wb_dat_i;
`endif
start_dlc <= 1'b1; // enable DL counter
tf_push <= 1'b0;
end
else
begin
tf_push <= 1'b1;
start_dlc <= 1'b0;
end // else: !if(dlab)
else
begin
start_dlc <= 1'b0;
tf_push <= 1'b0;
end // else: !if(dlab)

// Receiver FIFO trigger level selection logic (asynchronous mux)
always @(fcr)
case (fcr[`UART_FC_TL])
2'b00 : trigger_level = 1;
2'b01 : trigger_level = 4;
2'b10 : trigger_level = 8;
2'b11 : trigger_level = 14;
endcase // case(fcr[`UART_FC_TL])
//
// STATUS REGISTERS //
//

// Modem Status Register
reg [3:0] delayed_modem_signals;
always @(posedge clk or posedge wb_rst_i)
begin
if (wb_rst_i)
begin
msr <= 0;
delayed_modem_signals[3:0] <= 0;
end
else begin
msr[`UART_MS_DDCD:`UART_MS_DCTS] <= msi_reset ? 4'b0 :
msr[`UART_MS_DDCD:`UART_MS_DCTS] | ({dcd, ri, dsr, cts} ^ delayed_modem_signals[3:0]);
msr[`UART_MS_CDCD:`UART_MS_CCTS] <= {dcd_c, ri_c, dsr_c, cts_c};
delayed_modem_signals[3:0] <= {dcd, ri, dsr, cts};
end
end


// Line Status Register

// activation conditions
assign lsr0 = (rf_count==0 && rf_push_pulse); // data in receiver fifo available set condition
assign lsr1 = rf_overrun; // Receiver overrun error
assign lsr2 = rf_data_out[1]; // parity error bit
assign lsr3 = rf_data_out[0]; // framing error bit
assign lsr4 = rf_data_out[2]; // break error in the character
assign lsr5 = (tf_count==5'b0 && thre_set_en); // transmitter fifo is empty
assign lsr6 = (tf_count==5'b0 && thre_set_en && (tstate == /*`S_IDLE */ 0)); // transmitter empty
assign lsr7 = rf_error_bit | rf_overrun;

// lsr bit0 (receiver data available)
reg lsr0_d;

always @(posedge clk or posedge wb_rst_i)
if (wb_rst_i) lsr0_d <= 0;
else lsr0_d <= lsr0;

always @(posedge clk or posedge wb_rst_i)
if (wb_rst_i) lsr0r <= 0;
else lsr0r <= (rf_count==1 && rf_pop && !rf_push_pulse || rx_reset) ? 1'b0 : // deassert condition
lsr0r || (lsr0 && ~lsr0_d); // set on rise of lsr0 and keep asserted until deasserted

// lsr bit 1 (receiver overrun)
reg lsr1_d; // delayed

always @(posedge clk or posedge wb_rst_i)
if (wb_rst_i) lsr1_d <= 0;
else lsr1_d <= lsr1;

always @(posedge clk or posedge wb_rst_i)
if (wb_rst_i) lsr1r <= 0;
else lsr1r <= lsr_mask ? 1'b0 : lsr1r || (lsr1 && ~lsr1_d); // set on rise

// lsr bit 2 (parity error)
reg lsr2_d; // delayed

always @(posedge clk or posedge wb_rst_i)
if (wb_rst_i) lsr2_d <= 0;
else lsr2_d <= lsr2;

always @(posedge clk or posedge wb_rst_i)
if (wb_rst_i) lsr2r <= 0;
else lsr2r <= lsr_mask ? 1'b0 : lsr2r || (lsr2 && ~lsr2_d); // set on rise

// lsr bit 3 (framing error)
reg lsr3_d; // delayed

always @(posedge clk or posedge wb_rst_i)
if (wb_rst_i) lsr3_d <= 0;
else lsr3_d <= lsr3;

always @(posedge clk or posedge wb_rst_i)
if (wb_rst_i) lsr3r <= 0;
else lsr3r <= lsr_mask ? 1'b0 : lsr3r || (lsr3 && ~lsr3_d); // set on rise

// lsr bit 4 (break indicator)
reg lsr4_d; // delayed

always @(posedge clk or posedge wb_rst_i)
if (wb_rst_i) lsr4_d <= 0;
else lsr4_d <= lsr4;

always @(posedge clk or posedge wb_rst_i)
if (wb_rst_i) lsr4r <= 0;
else lsr4r <= lsr_mask ? 1'b0 : lsr4r || (lsr4 && ~lsr4_d);

// lsr bit 5 (transmitter fifo is empty)
reg lsr5_d;

always @(posedge clk or posedge wb_rst_i)
if (wb_rst_i) lsr5_d <= 1;
else lsr5_d <= lsr5;

always @(posedge clk or posedge wb_rst_i)
if (wb_rst_i) lsr5r <= 1;
else lsr5r <= (fifo_write) ? 1'b0 : lsr5r || (lsr5 && ~lsr5_d);

// lsr bit 6 (transmitter empty indicator)
reg lsr6_d;

always @(posedge clk or posedge wb_rst_i)
if (wb_rst_i) lsr6_d <= 1;
else lsr6_d <= lsr6;

always @(posedge clk or posedge wb_rst_i)
if (wb_rst_i) lsr6r <= 1;
else lsr6r <= (fifo_write) ? 1'b0 : lsr6r || (lsr6 && ~lsr6_d);

// lsr bit 7 (error in fifo)
reg lsr7_d;

always @(posedge clk or posedge wb_rst_i)
if (wb_rst_i) lsr7_d <= 0;
else lsr7_d <= lsr7;

always @(posedge clk or posedge wb_rst_i)
if (wb_rst_i) lsr7r <= 0;
else lsr7r <= lsr_mask ? 1'b0 : lsr7r || (lsr7 && ~lsr7_d);

// Frequency divider
always @(posedge clk or posedge wb_rst_i)
begin
if (wb_rst_i)
dlc <= 0;
else
if (start_dlc | ~ (|dlc))
dlc <= dl - 16'd1; // preset counter
else
dlc <= dlc - 16'd1; // decrement counter
end

// Enable signal generation logic
always @(posedge clk or posedge wb_rst_i)
begin
if (wb_rst_i)
enable <= 1'b0;
else
if (|dl & ~(|dlc)) // dl>0 & dlc==0
enable <= 1'b1;
else
enable <= 1'b0;
end

// Delaying THRE status for one character cycle after a character is written to an empty fifo.
always @(lcr)
case (lcr[3:0])
4'b0000 : block_value = 95; // 6 bits
4'b0100 : block_value = 103; // 6.5 bits
4'b0001, 4'b1000 : block_value = 111; // 7 bits
4'b1100 : block_value = 119; // 7.5 bits
4'b0010, 4'b0101, 4'b1001 : block_value = 127; // 8 bits
4'b0011, 4'b0110, 4'b1010, 4'b1101 : block_value = 143; // 9 bits
4'b0111, 4'b1011, 4'b1110 : block_value = 159; // 10 bits
4'b1111 : block_value = 175; // 11 bits
endcase // case(lcr[3:0])

// Counting time of one character minus stop bit
always @(posedge clk or posedge wb_rst_i)
begin
if (wb_rst_i)
block_cnt <= 8'd0;
else
if(lsr5r & fifo_write) // THRE bit set & write to fifo occured
block_cnt <= SIM ? 8'd1 : block_value;
else
if (enable & block_cnt != 8'b0) // only work on enable times
block_cnt <= block_cnt - 8'd1; // decrement break counter
end // always of break condition detection

// Generating THRE status enable signal
assign thre_set_en = ~(|block_cnt);


//
// INTERRUPT LOGIC
//

assign rls_int = ier[`UART_IE_RLS] && (lsr[`UART_LS_OE] || lsr[`UART_LS_PE] || lsr[`UART_LS_FE] || lsr[`UART_LS_BI]);
assign rda_int = ier[`UART_IE_RDA] && (rf_count >= {1'b0,trigger_level});
assign thre_int = ier[`UART_IE_THRE] && lsr[`UART_LS_TFE];
assign ms_int = ier[`UART_IE_MS] && (| msr[3:0]);
assign ti_int = ier[`UART_IE_RDA] && (counter_t == 10'b0) && (|rf_count);

reg rls_int_d;
reg thre_int_d;
reg ms_int_d;
reg ti_int_d;
reg rda_int_d;

// delay lines
always @(posedge clk or posedge wb_rst_i)
if (wb_rst_i) rls_int_d <= 0;
else rls_int_d <= rls_int;

always @(posedge clk or posedge wb_rst_i)
if (wb_rst_i) rda_int_d <= 0;
else rda_int_d <= rda_int;

always @(posedge clk or posedge wb_rst_i)
if (wb_rst_i) thre_int_d <= 0;
else thre_int_d <= thre_int;

always @(posedge clk or posedge wb_rst_i)
if (wb_rst_i) ms_int_d <= 0;
else ms_int_d <= ms_int;

always @(posedge clk or posedge wb_rst_i)
if (wb_rst_i) ti_int_d <= 0;
else ti_int_d <= ti_int;

// rise detection signals

wire rls_int_rise;
wire thre_int_rise;
wire ms_int_rise;
wire ti_int_rise;
wire rda_int_rise;

assign rda_int_rise = rda_int & ~rda_int_d;
assign rls_int_rise = rls_int & ~rls_int_d;
assign thre_int_rise = thre_int & ~thre_int_d;
assign ms_int_rise = ms_int & ~ms_int_d;
assign ti_int_rise = ti_int & ~ti_int_d;

// interrupt pending flags
reg rls_int_pnd;
reg rda_int_pnd;
reg thre_int_pnd;
reg ms_int_pnd;
reg ti_int_pnd;

// interrupt pending flags assignments
always @(posedge clk or posedge wb_rst_i)
if (wb_rst_i) rls_int_pnd <= 0;
else
rls_int_pnd <= lsr_mask ? 1'b0 : // reset condition
rls_int_rise ? 1'b1 : // latch condition
rls_int_pnd && ier[`UART_IE_RLS]; // default operation: remove if masked

always @(posedge clk or posedge wb_rst_i)
if (wb_rst_i) rda_int_pnd <= 0;
else
rda_int_pnd <= ((rf_count == {1'b0,trigger_level}) && fifo_read) ? 1'b0 : // reset condition
rda_int_rise ? 1'b1 : // latch condition
rda_int_pnd && ier[`UART_IE_RDA]; // default operation: remove if masked

always @(posedge clk or posedge wb_rst_i)
if (wb_rst_i) thre_int_pnd <= 0;
else
thre_int_pnd <= fifo_write || (iir_read & ~iir[`UART_II_IP] & iir[`UART_II_II] == `UART_II_THRE)? 1'b0 :
thre_int_rise ? 1'b1 :
thre_int_pnd && ier[`UART_IE_THRE];

always @(posedge clk or posedge wb_rst_i)
if (wb_rst_i) ms_int_pnd <= 0;
else
ms_int_pnd <= msr_read ? 1'b0 :
ms_int_rise ? 1'b1 :
ms_int_pnd && ier[`UART_IE_MS];

always @(posedge clk or posedge wb_rst_i)
if (wb_rst_i) ti_int_pnd <= 0;
else
ti_int_pnd <= fifo_read ? 1'b0 :
ti_int_rise ? 1'b1 :
ti_int_pnd && ier[`UART_IE_RDA];
// end of pending flags

// INT_O logic
always @(posedge clk or posedge wb_rst_i)
begin
if (wb_rst_i)
int_o <= 1'b0;
else
int_o <=
rls_int_pnd ? ~lsr_mask :
rda_int_pnd ? 1'b1 :
ti_int_pnd ? ~fifo_read :
thre_int_pnd ? !(fifo_write & iir_read) :
ms_int_pnd ? ~msr_read :
1'd0; // if no interrupt are pending
end


// Interrupt Identification register
always @(posedge clk or posedge wb_rst_i)
begin
if (wb_rst_i)
iir <= 1;
else
if (rls_int_pnd) // interrupt is pending
begin
iir[`UART_II_II] <= `UART_II_RLS; // set identification register to correct value
iir[`UART_II_IP] <= 1'b0; // and clear the IIR bit 0 (interrupt pending)
end else // the sequence of conditions determines priority of interrupt identification
if (rda_int)
begin
iir[`UART_II_II] <= `UART_II_RDA;
iir[`UART_II_IP] <= 1'b0;
end
else if (ti_int_pnd)
begin
iir[`UART_II_II] <= `UART_II_TI;
iir[`UART_II_IP] <= 1'b0;
end
else if (thre_int_pnd)
begin
iir[`UART_II_II] <= `UART_II_THRE;
iir[`UART_II_IP] <= 1'b0;
end
else if (ms_int_pnd)
begin
iir[`UART_II_II] <= `UART_II_MS;
iir[`UART_II_IP] <= 1'b0;
end else // no interrupt is pending
begin
iir[`UART_II_II] <= 0;
iir[`UART_II_IP] <= 1'b1;
end
end

endmodule

@ -0,0 +1,316 @@
//////////////////////////////////////////////////////////////////////
//// ////
//// uart_rfifo.v (Modified from uart_fifo.v) ////
//// ////
//// ////
//// This file is part of the "UART 16550 compatible" project ////
//// http://www.opencores.org/cores/uart16550/ ////
//// ////
//// Documentation related to this project: ////
//// - http://www.opencores.org/cores/uart16550/ ////
//// ////
//// Projects compatibility: ////
//// - WISHBONE ////
//// RS232 Protocol ////
//// 16550D uart (mostly supported) ////
//// ////
//// Overview (main Features): ////
//// UART core receiver FIFO ////
//// ////
//// To Do: ////
//// Nothing. ////
//// ////
//// Author(s): ////
//// - gorban@opencores.org ////
//// - Jacob Gorban ////
//// - Igor Mohor (igorm@opencores.org) ////
//// ////
//// Created: 2001/05/12 ////
//// Last Updated: 2002/07/22 ////
//// (See log for the revision history) ////
//// ////
//// ////
//////////////////////////////////////////////////////////////////////
//// ////
//// Copyright (C) 2000, 2001 Authors ////
//// ////
//// This source file may be used and distributed without ////
//// restriction provided that this copyright statement is not ////
//// removed from the file and that any derivative work contains ////
//// the original copyright notice and the associated disclaimer. ////
//// ////
//// This source file is free software; you can redistribute it ////
//// and/or modify it under the terms of the GNU Lesser General ////
//// Public License as published by the Free Software Foundation; ////
//// either version 2.1 of the License, or (at your option) any ////
//// later version. ////
//// ////
//// This source is distributed in the hope that it will be ////
//// useful, but WITHOUT ANY WARRANTY; without even the implied ////
//// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR ////
//// PURPOSE. See the GNU Lesser General Public License for more ////
//// details. ////
//// ////
//// You should have received a copy of the GNU Lesser General ////
//// Public License along with this source; if not, download it ////
//// from http://www.opencores.org/lgpl.shtml ////
//// ////
//////////////////////////////////////////////////////////////////////
//
// CVS Revision History
//
// $Log: not supported by cvs2svn $
// Revision 1.3 2003/06/11 16:37:47 gorban
// This fixes errors in some cases when data is being read and put to the FIFO at the same time. Patch is submitted by Scott Furman. Update is very recommended.
//
// Revision 1.2 2002/07/29 21:16:18 gorban
// The uart_defines.v file is included again in sources.
//
// Revision 1.1 2002/07/22 23:02:23 gorban
// Bug Fixes:
// * Possible loss of sync and bad reception of stop bit on slow baud rates fixed.
// Problem reported by Kenny.Tung.
// * Bad (or lack of ) loopback handling fixed. Reported by Cherry Withers.
//
// Improvements:
// * Made FIFO's as general inferrable memory where possible.
// So on FPGA they should be inferred as RAM (Distributed RAM on Xilinx).
// This saves about 1/3 of the Slice count and reduces P&R and synthesis times.
//
// * Added optional baudrate output (baud_o).
// This is identical to BAUDOUT* signal on 16550 chip.
// It outputs 16xbit_clock_rate - the divided clock.
// It's disabled by default. Define UART_HAS_BAUDRATE_OUTPUT to use.
//
// Revision 1.16 2001/12/20 13:25:46 mohor
// rx push changed to be only one cycle wide.
//
// Revision 1.15 2001/12/18 09:01:07 mohor
// Bug that was entered in the last update fixed (rx state machine).
//
// Revision 1.14 2001/12/17 14:46:48 mohor
// overrun signal was moved to separate block because many sequential lsr
// reads were preventing data from being written to rx fifo.
// underrun signal was not used and was removed from the project.
//
// Revision 1.13 2001/11/26 21:38:54 gorban
// Lots of fixes:
// Break condition wasn't handled correctly at all.
// LSR bits could lose their values.
// LSR value after reset was wrong.
// Timing of THRE interrupt signal corrected.
// LSR bit 0 timing corrected.
//
// Revision 1.12 2001/11/08 14:54:23 mohor
// Comments in Slovene language deleted, few small fixes for better work of
// old tools. IRQs need to be fix.
//
// Revision 1.11 2001/11/07 17:51:52 gorban
// Heavily rewritten interrupt and LSR subsystems.
// Many bugs hopefully squashed.
//
// Revision 1.10 2001/10/20 09:58:40 gorban
// Small synopsis fixes
//
// Revision 1.9 2001/08/24 21:01:12 mohor
// Things connected to parity changed.
// Clock devider changed.
//
// Revision 1.8 2001/08/24 08:48:10 mohor
// FIFO was not cleared after the data was read bug fixed.
//
// Revision 1.7 2001/08/23 16:05:05 mohor
// Stop bit bug fixed.
// Parity bug fixed.
// WISHBONE read cycle bug fixed,
// OE indicator (Overrun Error) bug fixed.
// PE indicator (Parity Error) bug fixed.
// Register read bug fixed.
//
// Revision 1.3 2001/05/31 20:08:01 gorban
// FIFO changes and other corrections.
//
// Revision 1.3 2001/05/27 17:37:48 gorban
// Fixed many bugs. Updated spec. Changed FIFO files structure. See CHANGES.txt file.
//
// Revision 1.2 2001/05/17 18:34:18 gorban
// First 'stable' release. Should be sythesizable now. Also added new header.
//
// Revision 1.0 2001-05-17 21:27:12+02 jacob
// Initial revision
//
//

`include "uart_defines.v"

module uart_rfifo (clk,
wb_rst_i, data_in, data_out,
// Control signals
push, // push strobe, active high
pop, // pop strobe, active high
// status signals
overrun,
count,
error_bit,
fifo_reset,
reset_status
);


// FIFO parameters
parameter fifo_width = `UART_FIFO_WIDTH;
parameter fifo_depth = `UART_FIFO_DEPTH;
parameter fifo_pointer_w = `UART_FIFO_POINTER_W;
parameter fifo_counter_w = `UART_FIFO_COUNTER_W;

input clk;
input wb_rst_i;
input push;
input pop;
input [fifo_width-1:0] data_in;
input fifo_reset;
input reset_status;

output [fifo_width-1:0] data_out;
output overrun;
output [fifo_counter_w-1:0] count;
output error_bit;

wire [fifo_width-1:0] data_out;
wire [7:0] data8_out;
// flags FIFO
reg [2:0] fifo[fifo_depth-1:0];

// FIFO pointers
reg [fifo_pointer_w-1:0] top;
reg [fifo_pointer_w-1:0] bottom;

reg [fifo_counter_w-1:0] count;
reg overrun;

wire [fifo_pointer_w-1:0] top_plus_1 = top + 4'h1;

raminfr #(fifo_pointer_w,8,fifo_depth) rfifo
(.clk(clk),
.we(push),
.a(top),
.dpra(bottom),
.di(data_in[fifo_width-1:fifo_width-8]),
.dpo(data8_out)
);

always @(posedge clk or posedge wb_rst_i) // synchronous FIFO
begin
if (wb_rst_i)
begin
top <= 0;
bottom <= 0;
count <= 0;
fifo[0] <= 0;
fifo[1] <= 0;
fifo[2] <= 0;
fifo[3] <= 0;
fifo[4] <= 0;
fifo[5] <= 0;
fifo[6] <= 0;
fifo[7] <= 0;
fifo[8] <= 0;
fifo[9] <= 0;
fifo[10] <= 0;
fifo[11] <= 0;
fifo[12] <= 0;
fifo[13] <= 0;
fifo[14] <= 0;
fifo[15] <= 0;
end
else
if (fifo_reset) begin
top <= 0;
bottom <= 0;
count <= 0;
fifo[0] <= 0;
fifo[1] <= 0;
fifo[2] <= 0;
fifo[3] <= 0;
fifo[4] <= 0;
fifo[5] <= 0;
fifo[6] <= 0;
fifo[7] <= 0;
fifo[8] <= 0;
fifo[9] <= 0;
fifo[10] <= 0;
fifo[11] <= 0;
fifo[12] <= 0;
fifo[13] <= 0;
fifo[14] <= 0;
fifo[15] <= 0;
end
else
begin
case ({push, pop})
2'b10 : if (count<fifo_depth) // overrun condition
begin
top <= top_plus_1;
fifo[top] <= data_in[2:0];
count <= count + 5'd1;
end
2'b01 : if(count>0)
begin
fifo[bottom] <= 0;
bottom <= bottom + 4'd1;
count <= count - 5'd1;
end
2'b11 : begin
bottom <= bottom + 4'd1;
top <= top_plus_1;
fifo[top] <= data_in[2:0];
end
default: ;
endcase
end
end // always

always @(posedge clk or posedge wb_rst_i) // synchronous FIFO
begin
if (wb_rst_i)
overrun <= 1'b0;
else
if(fifo_reset | reset_status)
overrun <= 1'b0;
else
if(push & ~pop & (count==fifo_depth))
overrun <= 1'b1;
end // always


// please note though that data_out is only valid one clock after pop signal
assign data_out = {data8_out,fifo[bottom]};

// Additional logic for detection of error conditions (parity and framing) inside the FIFO
// for the Line Status Register bit 7

wire [2:0] word0 = fifo[0];
wire [2:0] word1 = fifo[1];
wire [2:0] word2 = fifo[2];
wire [2:0] word3 = fifo[3];
wire [2:0] word4 = fifo[4];
wire [2:0] word5 = fifo[5];
wire [2:0] word6 = fifo[6];
wire [2:0] word7 = fifo[7];

wire [2:0] word8 = fifo[8];
wire [2:0] word9 = fifo[9];
wire [2:0] word10 = fifo[10];
wire [2:0] word11 = fifo[11];
wire [2:0] word12 = fifo[12];
wire [2:0] word13 = fifo[13];
wire [2:0] word14 = fifo[14];
wire [2:0] word15 = fifo[15];

// a 1 is returned if any of the error bits in the fifo is 1
assign error_bit = |(word0[2:0] | word1[2:0] | word2[2:0] | word3[2:0] |
word4[2:0] | word5[2:0] | word6[2:0] | word7[2:0] |
word8[2:0] | word9[2:0] | word10[2:0] | word11[2:0] |
word12[2:0] | word13[2:0] | word14[2:0] | word15[2:0] );

endmodule

@ -0,0 +1,117 @@
//////////////////////////////////////////////////////////////////////
//// ////
//// uart_sync_flops.v ////
//// ////
//// ////
//// This file is part of the "UART 16550 compatible" project ////
//// http://www.opencores.org/cores/uart16550/ ////
//// ////
//// Documentation related to this project: ////
//// - http://www.opencores.org/cores/uart16550/ ////
//// ////
//// Projects compatibility: ////
//// - WISHBONE ////
//// RS232 Protocol ////
//// 16550D uart (mostly supported) ////
//// ////
//// Overview (main Features): ////
//// UART core receiver logic ////
//// ////
//// Known problems (limits): ////
//// None known ////
//// ////
//// To Do: ////
//// Thourough testing. ////
//// ////
//// Author(s): ////
//// - Andrej Erzen (andreje@flextronics.si) ////
//// - Tadej Markovic (tadejm@flextronics.si) ////
//// ////
//// Created: 2004/05/20 ////
//// Last Updated: 2004/05/20 ////
//// (See log for the revision history) ////
//// ////
//// ////
//////////////////////////////////////////////////////////////////////
//// ////
//// Copyright (C) 2000, 2001 Authors ////
//// ////
//// This source file may be used and distributed without ////
//// restriction provided that this copyright statement is not ////
//// removed from the file and that any derivative work contains ////
//// the original copyright notice and the associated disclaimer. ////
//// ////
//// This source file is free software; you can redistribute it ////
//// and/or modify it under the terms of the GNU Lesser General ////
//// Public License as published by the Free Software Foundation; ////
//// either version 2.1 of the License, or (at your option) any ////
//// later version. ////
//// ////
//// This source is distributed in the hope that it will be ////
//// useful, but WITHOUT ANY WARRANTY; without even the implied ////
//// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR ////
//// PURPOSE. See the GNU Lesser General Public License for more ////
//// details. ////
//// ////
//// You should have received a copy of the GNU Lesser General ////
//// Public License along with this source; if not, download it ////
//// from http://www.opencores.org/lgpl.shtml ////
//// ////
//////////////////////////////////////////////////////////////////////
//
// CVS Revision History
//
// $Log: not supported by cvs2svn $
//

module uart_sync_flops
(
// internal signals
rst_i,
clk_i,
stage1_rst_i,
stage1_clk_en_i,
async_dat_i,
sync_dat_o
);

parameter width = 1;
parameter init_value = 1'b0;

input rst_i; // reset input
input clk_i; // clock input
input stage1_rst_i; // synchronous reset for stage 1 FF
input stage1_clk_en_i; // synchronous clock enable for stage 1 FF
input [width-1:0] async_dat_i; // asynchronous data input
output [width-1:0] sync_dat_o; // synchronous data output


//
// Interal signal declarations
//

reg [width-1:0] sync_dat_o;
reg [width-1:0] flop_0;


// first stage
always @ (posedge clk_i or posedge rst_i)
begin
if (rst_i)
flop_0 <= {width{init_value}};
else
flop_0 <= async_dat_i;
end

// second stage
always @ (posedge clk_i or posedge rst_i)
begin
if (rst_i)
sync_dat_o <= {width{init_value}};
else if (stage1_rst_i)
sync_dat_o <= {width{init_value}};
else if (stage1_clk_en_i)
sync_dat_o <= flop_0;
end

endmodule

@ -0,0 +1,239 @@
//////////////////////////////////////////////////////////////////////
//// ////
//// uart_tfifo.v ////
//// ////
//// ////
//// This file is part of the "UART 16550 compatible" project ////
//// http://www.opencores.org/cores/uart16550/ ////
//// ////
//// Documentation related to this project: ////
//// - http://www.opencores.org/cores/uart16550/ ////
//// ////
//// Projects compatibility: ////
//// - WISHBONE ////
//// RS232 Protocol ////
//// 16550D uart (mostly supported) ////
//// ////
//// Overview (main Features): ////
//// UART core transmitter FIFO ////
//// ////
//// To Do: ////
//// Nothing. ////
//// ////
//// Author(s): ////
//// - gorban@opencores.org ////
//// - Jacob Gorban ////
//// - Igor Mohor (igorm@opencores.org) ////
//// ////
//// Created: 2001/05/12 ////
//// Last Updated: 2002/07/22 ////
//// (See log for the revision history) ////
//// ////
//// ////
//////////////////////////////////////////////////////////////////////
//// ////
//// Copyright (C) 2000, 2001 Authors ////
//// ////
//// This source file may be used and distributed without ////
//// restriction provided that this copyright statement is not ////
//// removed from the file and that any derivative work contains ////
//// the original copyright notice and the associated disclaimer. ////
//// ////
//// This source file is free software; you can redistribute it ////
//// and/or modify it under the terms of the GNU Lesser General ////
//// Public License as published by the Free Software Foundation; ////
//// either version 2.1 of the License, or (at your option) any ////
//// later version. ////
//// ////
//// This source is distributed in the hope that it will be ////
//// useful, but WITHOUT ANY WARRANTY; without even the implied ////
//// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR ////
//// PURPOSE. See the GNU Lesser General Public License for more ////
//// details. ////
//// ////
//// You should have received a copy of the GNU Lesser General ////
//// Public License along with this source; if not, download it ////
//// from http://www.opencores.org/lgpl.shtml ////
//// ////
//////////////////////////////////////////////////////////////////////
//
// CVS Revision History
//
// $Log: not supported by cvs2svn $
// Revision 1.1 2002/07/22 23:02:23 gorban
// Bug Fixes:
// * Possible loss of sync and bad reception of stop bit on slow baud rates fixed.
// Problem reported by Kenny.Tung.
// * Bad (or lack of ) loopback handling fixed. Reported by Cherry Withers.
//
// Improvements:
// * Made FIFO's as general inferrable memory where possible.
// So on FPGA they should be inferred as RAM (Distributed RAM on Xilinx).
// This saves about 1/3 of the Slice count and reduces P&R and synthesis times.
//
// * Added optional baudrate output (baud_o).
// This is identical to BAUDOUT* signal on 16550 chip.
// It outputs 16xbit_clock_rate - the divided clock.
// It's disabled by default. Define UART_HAS_BAUDRATE_OUTPUT to use.
//
// Revision 1.16 2001/12/20 13:25:46 mohor
// rx push changed to be only one cycle wide.
//
// Revision 1.15 2001/12/18 09:01:07 mohor
// Bug that was entered in the last update fixed (rx state machine).
//
// Revision 1.14 2001/12/17 14:46:48 mohor
// overrun signal was moved to separate block because many sequential lsr
// reads were preventing data from being written to rx fifo.
// underrun signal was not used and was removed from the project.
//
// Revision 1.13 2001/11/26 21:38:54 gorban
// Lots of fixes:
// Break condition wasn't handled correctly at all.
// LSR bits could lose their values.
// LSR value after reset was wrong.
// Timing of THRE interrupt signal corrected.
// LSR bit 0 timing corrected.
//
// Revision 1.12 2001/11/08 14:54:23 mohor
// Comments in Slovene language deleted, few small fixes for better work of
// old tools. IRQs need to be fix.
//
// Revision 1.11 2001/11/07 17:51:52 gorban
// Heavily rewritten interrupt and LSR subsystems.
// Many bugs hopefully squashed.
//
// Revision 1.10 2001/10/20 09:58:40 gorban
// Small synopsis fixes
//
// Revision 1.9 2001/08/24 21:01:12 mohor
// Things connected to parity changed.
// Clock devider changed.
//
// Revision 1.8 2001/08/24 08:48:10 mohor
// FIFO was not cleared after the data was read bug fixed.
//
// Revision 1.7 2001/08/23 16:05:05 mohor
// Stop bit bug fixed.
// Parity bug fixed.
// WISHBONE read cycle bug fixed,
// OE indicator (Overrun Error) bug fixed.
// PE indicator (Parity Error) bug fixed.
// Register read bug fixed.
//
// Revision 1.3 2001/05/31 20:08:01 gorban
// FIFO changes and other corrections.
//
// Revision 1.3 2001/05/27 17:37:48 gorban
// Fixed many bugs. Updated spec. Changed FIFO files structure. See CHANGES.txt file.
//
// Revision 1.2 2001/05/17 18:34:18 gorban
// First 'stable' release. Should be sythesizable now. Also added new header.
//
// Revision 1.0 2001-05-17 21:27:12+02 jacob
// Initial revision
//
//

`include "uart_defines.v"

module uart_tfifo (clk,
wb_rst_i, data_in, data_out,
// Control signals
push, // push strobe, active high
pop, // pop strobe, active high
// status signals
overrun,
count,
fifo_reset,
reset_status
);


// FIFO parameters
parameter fifo_width = `UART_FIFO_WIDTH;
parameter fifo_depth = `UART_FIFO_DEPTH;
parameter fifo_pointer_w = `UART_FIFO_POINTER_W;
parameter fifo_counter_w = `UART_FIFO_COUNTER_W;

input clk;
input wb_rst_i;
input push;
input pop;
input [fifo_width-1:0] data_in;
input fifo_reset;
input reset_status;

output [fifo_width-1:0] data_out;
output overrun;
output [fifo_counter_w-1:0] count;

wire [fifo_width-1:0] data_out;

// FIFO pointers
reg [fifo_pointer_w-1:0] top;
reg [fifo_pointer_w-1:0] bottom;

reg [fifo_counter_w-1:0] count;
reg overrun;
wire [fifo_pointer_w-1:0] top_plus_1 = top + 4'd1;

raminfr #(fifo_pointer_w,fifo_width,fifo_depth) tfifo
(.clk(clk),
.we(push),
.a(top),
.dpra(bottom),
.di(data_in),
.dpo(data_out)
);


always @(posedge clk or posedge wb_rst_i) // synchronous FIFO
begin
if (wb_rst_i)
begin
top <= 0;
bottom <= 0;
count <= 0;
end
else
if (fifo_reset) begin
top <= 0;
bottom <= 0;
count <= 0;
end
else
begin
case ({push, pop})
2'b10 : if (count<fifo_depth) // overrun condition
begin
top <= top_plus_1;
count <= count + 5'd1;
end
2'b01 : if(count>0)
begin
bottom <= bottom + 4'd1;
count <= count - 5'd1;
end
2'b11 : begin
bottom <= bottom + 4'd1;
top <= top_plus_1;
end
default: ;
endcase
end
end // always

always @(posedge clk or posedge wb_rst_i) // synchronous FIFO
begin
if (wb_rst_i)
overrun <= 1'b0;
else
if(fifo_reset | reset_status)
overrun <= 1'b0;
else
if(push & (count==fifo_depth))
overrun <= 1'b1;
end // always

endmodule

@ -0,0 +1,261 @@
//////////////////////////////////////////////////////////////////////
//// ////
//// uart_top.v ////
//// ////
//// ////
//// This file is part of the "UART 16550 compatible" project ////
//// http://www.opencores.org/cores/uart16550/ ////
//// ////
//// Documentation related to this project: ////
//// - http://www.opencores.org/cores/uart16550/ ////
//// ////
//// Projects compatibility: ////
//// - WISHBONE ////
//// RS232 Protocol ////
//// 16550D uart (mostly supported) ////
//// ////
//// Overview (main Features): ////
//// UART core top level. ////
//// ////
//// Known problems (limits): ////
//// Note that transmitter and receiver instances are inside ////
//// the uart_regs.v file. ////
//// ////
//// To Do: ////
//// Nothing so far. ////
//// ////
//// Author(s): ////
//// - gorban@opencores.org ////
//// - Jacob Gorban ////
//// - Igor Mohor (igorm@opencores.org) ////
//// ////
//// Created: 2001/05/12 ////
//// Last Updated: 2001/05/17 ////
//// (See log for the revision history) ////
//// ////
//// ////
//////////////////////////////////////////////////////////////////////
//// ////
//// Copyright (C) 2000, 2001 Authors ////
//// ////
//// This source file may be used and distributed without ////
//// restriction provided that this copyright statement is not ////
//// removed from the file and that any derivative work contains ////
//// the original copyright notice and the associated disclaimer. ////
//// ////
//// This source file is free software; you can redistribute it ////
//// and/or modify it under the terms of the GNU Lesser General ////
//// Public License as published by the Free Software Foundation; ////
//// either version 2.1 of the License, or (at your option) any ////
//// later version. ////
//// ////
//// This source is distributed in the hope that it will be ////
//// useful, but WITHOUT ANY WARRANTY; without even the implied ////
//// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR ////
//// PURPOSE. See the GNU Lesser General Public License for more ////
//// details. ////
//// ////
//// You should have received a copy of the GNU Lesser General ////
//// Public License along with this source; if not, download it ////
//// from http://www.opencores.org/lgpl.shtml ////
//// ////
//////////////////////////////////////////////////////////////////////
//
// CVS Revision History
//
// $Log: not supported by cvs2svn $
// Revision 1.18 2002/07/22 23:02:23 gorban
// Bug Fixes:
// * Possible loss of sync and bad reception of stop bit on slow baud rates fixed.
// Problem reported by Kenny.Tung.
// * Bad (or lack of ) loopback handling fixed. Reported by Cherry Withers.
//
// Improvements:
// * Made FIFO's as general inferrable memory where possible.
// So on FPGA they should be inferred as RAM (Distributed RAM on Xilinx).
// This saves about 1/3 of the Slice count and reduces P&R and synthesis times.
//
// * Added optional baudrate output (baud_o).
// This is identical to BAUDOUT* signal on 16550 chip.
// It outputs 16xbit_clock_rate - the divided clock.
// It's disabled by default. Define UART_HAS_BAUDRATE_OUTPUT to use.
//
// Revision 1.17 2001/12/19 08:40:03 mohor
// Warnings fixed (unused signals removed).
//
// Revision 1.16 2001/12/06 14:51:04 gorban
// Bug in LSR[0] is fixed.
// All WISHBONE signals are now sampled, so another wait-state is introduced on all transfers.
//
// Revision 1.15 2001/12/03 21:44:29 gorban
// Updated specification documentation.
// Added full 32-bit data bus interface, now as default.
// Address is 5-bit wide in 32-bit data bus mode.
// Added wb_sel_i input to the core. It's used in the 32-bit mode.
// Added debug interface with two 32-bit read-only registers in 32-bit mode.
// Bits 5 and 6 of LSR are now only cleared on TX FIFO write.
// My small test bench is modified to work with 32-bit mode.
//
// Revision 1.14 2001/11/07 17:51:52 gorban
// Heavily rewritten interrupt and LSR subsystems.
// Many bugs hopefully squashed.
//
// Revision 1.13 2001/10/20 09:58:40 gorban
// Small synopsis fixes
//
// Revision 1.12 2001/08/25 15:46:19 gorban
// Modified port names again
//
// Revision 1.11 2001/08/24 21:01:12 mohor
// Things connected to parity changed.
// Clock devider changed.
//
// Revision 1.10 2001/08/23 16:05:05 mohor
// Stop bit bug fixed.
// Parity bug fixed.
// WISHBONE read cycle bug fixed,
// OE indicator (Overrun Error) bug fixed.
// PE indicator (Parity Error) bug fixed.
// Register read bug fixed.
//
// Revision 1.4 2001/05/31 20:08:01 gorban
// FIFO changes and other corrections.
//
// Revision 1.3 2001/05/21 19:12:02 gorban
// Corrected some Linter messages.
//
// Revision 1.2 2001/05/17 18:34:18 gorban
// First 'stable' release. Should be sythesizable now. Also added new header.
//
// Revision 1.0 2001-05-17 21:27:12+02 jacob
// Initial revision
//
//

`include "uart_defines.v"

module uart_top (
wb_clk_i,
// Wishbone signals
wb_rst_i, wb_adr_i, wb_dat_i, wb_dat_o, wb_we_i, wb_stb_i, wb_cyc_i, wb_ack_o, wb_sel_i,
int_o, // interrupt request

// UART signals
// serial input/output
stx_pad_o, srx_pad_i,

// modem signals
rts_pad_o, cts_pad_i, dtr_pad_o, dsr_pad_i, ri_pad_i, dcd_pad_i
`ifdef UART_HAS_BAUDRATE_OUTPUT
, baud_o
`endif
);
parameter SIM = 0;
parameter debug = 0;

input wb_clk_i;

// WISHBONE interface
input wb_rst_i;
input [2:0] wb_adr_i;
input [7:0] wb_dat_i;
output [7:0] wb_dat_o;
input wb_we_i;
input wb_stb_i;
input wb_cyc_i;
input [3:0] wb_sel_i;
output wb_ack_o;
output int_o;

// UART signals
input srx_pad_i;
output stx_pad_o;
output rts_pad_o;
input cts_pad_i;
output dtr_pad_o;
input dsr_pad_i;
input ri_pad_i;
input dcd_pad_i;

// optional baudrate output
`ifdef UART_HAS_BAUDRATE_OUTPUT
output baud_o;
`endif


wire stx_pad_o;
wire rts_pad_o;
wire dtr_pad_o;

wire [2:0] wb_adr_i;
wire [7:0] wb_dat_i;
wire [7:0] wb_dat_o;

wire [7:0] wb_dat8_i; // 8-bit internal data input
wire [7:0] wb_dat8_o; // 8-bit internal data output
wire [31:0] wb_dat32_o; // debug interface 32-bit output
wire [3:0] wb_sel_i; // WISHBONE select signal
wire [2:0] wb_adr_int;
wire we_o; // Write enable for registers
wire re_o; // Read enable for registers
//
// MODULE INSTANCES
//

//// WISHBONE interface module
uart_wb wb_interface(
.clk( wb_clk_i ),
.wb_rst_i( wb_rst_i ),
.wb_dat_i(wb_dat_i),
.wb_dat_o(wb_dat_o),
.wb_dat8_i(wb_dat8_i),
.wb_dat8_o(wb_dat8_o),
.wb_dat32_o(32'b0),
.wb_sel_i(4'b0),
.wb_we_i( wb_we_i ),
.wb_stb_i( wb_stb_i ),
.wb_cyc_i( wb_cyc_i ),
.wb_ack_o( wb_ack_o ),
.wb_adr_i(wb_adr_i),
.wb_adr_int(wb_adr_int),
.we_o( we_o ),
.re_o(re_o)
);

// Registers
uart_regs #(.SIM (SIM)) regs(
.clk( wb_clk_i ),
.wb_rst_i( wb_rst_i ),
.wb_addr_i( wb_adr_int ),
.wb_dat_i( wb_dat8_i ),
.wb_dat_o( wb_dat8_o ),
.wb_we_i( we_o ),
.wb_re_i(re_o),
.modem_inputs( {cts_pad_i, dsr_pad_i,
ri_pad_i, dcd_pad_i} ),
.stx_pad_o( stx_pad_o ),
.srx_pad_i( srx_pad_i ),
.rts_pad_o( rts_pad_o ),
.dtr_pad_o( dtr_pad_o ),
.int_o( int_o )
`ifdef UART_HAS_BAUDRATE_OUTPUT
, .baud_o(baud_o)
`endif

);

initial
begin
if(debug) begin
`ifdef UART_HAS_BAUDRATE_OUTPUT
$display("(%m) UART INFO: Has baudrate output\n");
`else
$display("(%m) UART INFO: Doesn't have baudrate output\n");
`endif
end
end

endmodule


@ -0,0 +1,354 @@
//////////////////////////////////////////////////////////////////////
//// ////
//// uart_transmitter.v ////
//// ////
//// ////
//// This file is part of the "UART 16550 compatible" project ////
//// http://www.opencores.org/cores/uart16550/ ////
//// ////
//// Documentation related to this project: ////
//// - http://www.opencores.org/cores/uart16550/ ////
//// ////
//// Projects compatibility: ////
//// - WISHBONE ////
//// RS232 Protocol ////
//// 16550D uart (mostly supported) ////
//// ////
//// Overview (main Features): ////
//// UART core transmitter logic ////
//// ////
//// Known problems (limits): ////
//// None known ////
//// ////
//// To Do: ////
//// Thourough testing. ////
//// ////
//// Author(s): ////
//// - gorban@opencores.org ////
//// - Jacob Gorban ////
//// - Igor Mohor (igorm@opencores.org) ////
//// ////
//// Created: 2001/05/12 ////
//// Last Updated: 2001/05/17 ////
//// (See log for the revision history) ////
//// ////
//// ////
//////////////////////////////////////////////////////////////////////
//// ////
//// Copyright (C) 2000, 2001 Authors ////
//// ////
//// This source file may be used and distributed without ////
//// restriction provided that this copyright statement is not ////
//// removed from the file and that any derivative work contains ////
//// the original copyright notice and the associated disclaimer. ////
//// ////
//// This source file is free software; you can redistribute it ////
//// and/or modify it under the terms of the GNU Lesser General ////
//// Public License as published by the Free Software Foundation; ////
//// either version 2.1 of the License, or (at your option) any ////
//// later version. ////
//// ////
//// This source is distributed in the hope that it will be ////
//// useful, but WITHOUT ANY WARRANTY; without even the implied ////
//// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR ////
//// PURPOSE. See the GNU Lesser General Public License for more ////
//// details. ////
//// ////
//// You should have received a copy of the GNU Lesser General ////
//// Public License along with this source; if not, download it ////
//// from http://www.opencores.org/lgpl.shtml ////
//// ////
//////////////////////////////////////////////////////////////////////
//
// CVS Revision History
//
// $Log: not supported by cvs2svn $
// Revision 1.18 2002/07/22 23:02:23 gorban
// Bug Fixes:
// * Possible loss of sync and bad reception of stop bit on slow baud rates fixed.
// Problem reported by Kenny.Tung.
// * Bad (or lack of ) loopback handling fixed. Reported by Cherry Withers.
//
// Improvements:
// * Made FIFO's as general inferrable memory where possible.
// So on FPGA they should be inferred as RAM (Distributed RAM on Xilinx).
// This saves about 1/3 of the Slice count and reduces P&R and synthesis times.
//
// * Added optional baudrate output (baud_o).
// This is identical to BAUDOUT* signal on 16550 chip.
// It outputs 16xbit_clock_rate - the divided clock.
// It's disabled by default. Define UART_HAS_BAUDRATE_OUTPUT to use.
//
// Revision 1.16 2002/01/08 11:29:40 mohor
// tf_pop was too wide. Now it is only 1 clk cycle width.
//
// Revision 1.15 2001/12/17 14:46:48 mohor
// overrun signal was moved to separate block because many sequential lsr
// reads were preventing data from being written to rx fifo.
// underrun signal was not used and was removed from the project.
//
// Revision 1.14 2001/12/03 21:44:29 gorban
// Updated specification documentation.
// Added full 32-bit data bus interface, now as default.
// Address is 5-bit wide in 32-bit data bus mode.
// Added wb_sel_i input to the core. It's used in the 32-bit mode.
// Added debug interface with two 32-bit read-only registers in 32-bit mode.
// Bits 5 and 6 of LSR are now only cleared on TX FIFO write.
// My small test bench is modified to work with 32-bit mode.
//
// Revision 1.13 2001/11/08 14:54:23 mohor
// Comments in Slovene language deleted, few small fixes for better work of
// old tools. IRQs need to be fix.
//
// Revision 1.12 2001/11/07 17:51:52 gorban
// Heavily rewritten interrupt and LSR subsystems.
// Many bugs hopefully squashed.
//
// Revision 1.11 2001/10/29 17:00:46 gorban
// fixed parity sending and tx_fifo resets over- and underrun
//
// Revision 1.10 2001/10/20 09:58:40 gorban
// Small synopsis fixes
//
// Revision 1.9 2001/08/24 21:01:12 mohor
// Things connected to parity changed.
// Clock devider changed.
//
// Revision 1.8 2001/08/23 16:05:05 mohor
// Stop bit bug fixed.
// Parity bug fixed.
// WISHBONE read cycle bug fixed,
// OE indicator (Overrun Error) bug fixed.
// PE indicator (Parity Error) bug fixed.
// Register read bug fixed.
//
// Revision 1.6 2001/06/23 11:21:48 gorban
// DL made 16-bit long. Fixed transmission/reception bugs.
//
// Revision 1.5 2001/06/02 14:28:14 gorban
// Fixed receiver and transmitter. Major bug fixed.
//
// Revision 1.4 2001/05/31 20:08:01 gorban
// FIFO changes and other corrections.
//
// Revision 1.3 2001/05/27 17:37:49 gorban
// Fixed many bugs. Updated spec. Changed FIFO files structure. See CHANGES.txt file.
//
// Revision 1.2 2001/05/21 19:12:02 gorban
// Corrected some Linter messages.
//
// Revision 1.1 2001/05/17 18:34:18 gorban
// First 'stable' release. Should be sythesizable now. Also added new header.
//
// Revision 1.0 2001-05-17 21:27:12+02 jacob
// Initial revision
//
//

`include "uart_defines.v"

module uart_transmitter
#(parameter SIM = 0)
(clk, wb_rst_i, lcr, tf_push, wb_dat_i, enable, stx_pad_o, tstate, tf_count, tx_reset, lsr_mask);

input clk;
input wb_rst_i;
input [7:0] lcr;
input tf_push;
input [7:0] wb_dat_i;
input enable;
input tx_reset;
input lsr_mask; //reset of fifo
output stx_pad_o;
output [2:0] tstate;
output [`UART_FIFO_COUNTER_W-1:0] tf_count;

reg [2:0] tstate;
reg [4:0] counter;
reg [2:0] bit_counter; // counts the bits to be sent
reg [6:0] shift_out; // output shift register
reg stx_o_tmp;
reg parity_xor; // parity of the word
reg tf_pop;
reg bit_out;

// TX FIFO instance
//
// Transmitter FIFO signals
wire [`UART_FIFO_WIDTH-1:0] tf_data_in;
wire [`UART_FIFO_WIDTH-1:0] tf_data_out;
wire tf_push;
wire tf_overrun;
wire [`UART_FIFO_COUNTER_W-1:0] tf_count;

assign tf_data_in = wb_dat_i;

uart_tfifo fifo_tx( // error bit signal is not used in transmitter FIFO
.clk( clk ),
.wb_rst_i( wb_rst_i ),
.data_in( tf_data_in ),
.data_out( tf_data_out ),
.push( tf_push ),
.pop( tf_pop ),
.overrun( tf_overrun ),
.count( tf_count ),
.fifo_reset( tx_reset ),
.reset_status(lsr_mask)
);

// TRANSMITTER FINAL STATE MACHINE

localparam s_idle = 3'd0;
localparam s_send_start = 3'd1;
localparam s_send_byte = 3'd2;
localparam s_send_parity = 3'd3;
localparam s_send_stop = 3'd4;
localparam s_pop_byte = 3'd5;

always @(posedge clk or posedge wb_rst_i)
begin
if (wb_rst_i)
begin
tstate <= s_idle;
stx_o_tmp <= 1'b1;
counter <= 5'b0;
shift_out <= 7'b0;
bit_out <= 1'b0;
parity_xor <= 1'b0;
tf_pop <= 1'b0;
bit_counter <= 3'b0;
end
else
if (enable | SIM)
begin
case (tstate)
s_idle : if (~|tf_count) // if tf_count==0
begin
tstate <= s_idle;
stx_o_tmp <= 1'b1;
end
else
begin
tf_pop <= 1'b0;
stx_o_tmp <= 1'b1;
tstate <= s_pop_byte;
end
s_pop_byte : begin
tf_pop <= 1'b1;
case (lcr[/*`UART_LC_BITS*/1:0]) // number of bits in a word
2'b00 : begin
bit_counter <= 3'b100;
parity_xor <= ^tf_data_out[4:0];
end
2'b01 : begin
bit_counter <= 3'b101;
parity_xor <= ^tf_data_out[5:0];
end
2'b10 : begin
bit_counter <= 3'b110;
parity_xor <= ^tf_data_out[6:0];
end
2'b11 : begin
bit_counter <= 3'b111;
parity_xor <= ^tf_data_out[7:0];
end
endcase
{shift_out[6:0], bit_out} <= tf_data_out;
tstate <= s_send_start;
end
s_send_start : begin
tf_pop <= 1'b0;
if (~|counter)
counter <= 5'b01111;
else
if (counter == 5'b00001)
begin
counter <= 0;
tstate <= s_send_byte;
end
else
counter <= counter - 5'd1;
stx_o_tmp <= 1'b0;
if (SIM) begin
tstate <= s_idle;
$write("%c", tf_data_out);
$fflush(32'h80000001);
end
end
s_send_byte : begin
if (~|counter)
counter <= 5'b01111;
else
if (counter == 5'b00001)
begin
if (bit_counter > 3'b0)
begin
bit_counter <= bit_counter - 3'd1;
{shift_out[5:0],bit_out } <= {shift_out[6:1], shift_out[0]};
tstate <= s_send_byte;
end
else // end of byte
if (~lcr[`UART_LC_PE])
begin
tstate <= s_send_stop;
end
else
begin
case ({lcr[`UART_LC_EP],lcr[`UART_LC_SP]})
2'b00: bit_out <= ~parity_xor;
2'b01: bit_out <= 1'b1;
2'b10: bit_out <= parity_xor;
2'b11: bit_out <= 1'b0;
endcase
tstate <= s_send_parity;
end
counter <= 0;
end
else
counter <= counter - 5'd1;
stx_o_tmp <= bit_out; // set output pin
end
s_send_parity : begin
if (~|counter)
counter <= 5'b01111;
else
if (counter == 5'b00001)
begin
counter <= 5'd0;
tstate <= s_send_stop;
end
else
counter <= counter - 5'd1;
stx_o_tmp <= bit_out;
end
s_send_stop : begin
if (~|counter)
begin
casez ({lcr[`UART_LC_SB],lcr[`UART_LC_BITS]})
3'b0??: counter <= 5'b01101; // 1 stop bit ok igor
3'b100: counter <= 5'b10101; // 1.5 stop bit
default: counter <= 5'b11101; // 2 stop bits
endcase
end
else
if (counter == 5'b00001)
begin
counter <= 0;
tstate <= s_idle;
end
else
counter <= counter - 5'd1;
stx_o_tmp <= 1'b1;
end

default : // should never get here
tstate <= s_idle;
endcase
end // end if enable
else
tf_pop <= 1'b0; // tf_pop must be 1 cycle width
end // transmitter logic

assign stx_pad_o = lcr[`UART_LC_BC] ? 1'b0 : stx_o_tmp; // Break condition
endmodule

@ -0,0 +1,258 @@
//////////////////////////////////////////////////////////////////////
//// ////
//// uart_wb.v ////
//// ////
//// ////
//// This file is part of the "UART 16550 compatible" project ////
//// http://www.opencores.org/cores/uart16550/ ////
//// ////
//// Documentation related to this project: ////
//// - http://www.opencores.org/cores/uart16550/ ////
//// ////
//// Projects compatibility: ////
//// - WISHBONE ////
//// RS232 Protocol ////
//// 16550D uart (mostly supported) ////
//// ////
//// Overview (main Features): ////
//// UART core WISHBONE interface. ////
//// ////
//// Known problems (limits): ////
//// Inserts one wait state on all transfers. ////
//// Note affected signals and the way they are affected. ////
//// ////
//// To Do: ////
//// Nothing. ////
//// ////
//// Author(s): ////
//// - gorban@opencores.org ////
//// - Jacob Gorban ////
//// - Igor Mohor (igorm@opencores.org) ////
//// ////
//// Created: 2001/05/12 ////
//// Last Updated: 2001/05/17 ////
//// (See log for the revision history) ////
//// ////
//// ////
//////////////////////////////////////////////////////////////////////
//// ////
//// Copyright (C) 2000, 2001 Authors ////
//// ////
//// This source file may be used and distributed without ////
//// restriction provided that this copyright statement is not ////
//// removed from the file and that any derivative work contains ////
//// the original copyright notice and the associated disclaimer. ////
//// ////
//// This source file is free software; you can redistribute it ////
//// and/or modify it under the terms of the GNU Lesser General ////
//// Public License as published by the Free Software Foundation; ////
//// either version 2.1 of the License, or (at your option) any ////
//// later version. ////
//// ////
//// This source is distributed in the hope that it will be ////
//// useful, but WITHOUT ANY WARRANTY; without even the implied ////
//// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR ////
//// PURPOSE. See the GNU Lesser General Public License for more ////
//// details. ////
//// ////
//// You should have received a copy of the GNU Lesser General ////
//// Public License along with this source; if not, download it ////
//// from http://www.opencores.org/lgpl.shtml ////
//// ////
//////////////////////////////////////////////////////////////////////
//
// CVS Revision History
//
// $Log: not supported by cvs2svn $
// Revision 1.16 2002/07/29 21:16:18 gorban
// The uart_defines.v file is included again in sources.
//
// Revision 1.15 2002/07/22 23:02:23 gorban
// Bug Fixes:
// * Possible loss of sync and bad reception of stop bit on slow baud rates fixed.
// Problem reported by Kenny.Tung.
// * Bad (or lack of ) loopback handling fixed. Reported by Cherry Withers.
//
// Improvements:
// * Made FIFO's as general inferrable memory where possible.
// So on FPGA they should be inferred as RAM (Distributed RAM on Xilinx).
// This saves about 1/3 of the Slice count and reduces P&R and synthesis times.
//
// * Added optional baudrate output (baud_o).
// This is identical to BAUDOUT* signal on 16550 chip.
// It outputs 16xbit_clock_rate - the divided clock.
// It's disabled by default. Define UART_HAS_BAUDRATE_OUTPUT to use.
//
// Revision 1.12 2001/12/19 08:03:34 mohor
// Warnings cleared.
//
// Revision 1.11 2001/12/06 14:51:04 gorban
// Bug in LSR[0] is fixed.
// All WISHBONE signals are now sampled, so another wait-state is introduced on all transfers.
//
// Revision 1.10 2001/12/03 21:44:29 gorban
// Updated specification documentation.
// Added full 32-bit data bus interface, now as default.
// Address is 5-bit wide in 32-bit data bus mode.
// Added wb_sel_i input to the core. It's used in the 32-bit mode.
// Added debug interface with two 32-bit read-only registers in 32-bit mode.
// Bits 5 and 6 of LSR are now only cleared on TX FIFO write.
// My small test bench is modified to work with 32-bit mode.
//
// Revision 1.9 2001/10/20 09:58:40 gorban
// Small synopsis fixes
//
// Revision 1.8 2001/08/24 21:01:12 mohor
// Things connected to parity changed.
// Clock devider changed.
//
// Revision 1.7 2001/08/23 16:05:05 mohor
// Stop bit bug fixed.
// Parity bug fixed.
// WISHBONE read cycle bug fixed,
// OE indicator (Overrun Error) bug fixed.
// PE indicator (Parity Error) bug fixed.
// Register read bug fixed.
//
// Revision 1.4 2001/05/31 20:08:01 gorban
// FIFO changes and other corrections.
//
// Revision 1.3 2001/05/21 19:12:01 gorban
// Corrected some Linter messages.
//
// Revision 1.2 2001/05/17 18:34:18 gorban
// First 'stable' release. Should be sythesizable now. Also added new header.
//
// Revision 1.0 2001-05-17 21:27:13+02 jacob
// Initial revision
//
//

// UART core WISHBONE interface
//
// Author: Jacob Gorban (jacob.gorban@flextronicssemi.com)
// Company: Flextronics Semiconductor
//

`include "uart_defines.v"
module uart_wb (clk, wb_rst_i,
wb_we_i, wb_stb_i, wb_cyc_i, wb_ack_o, wb_adr_i,
wb_adr_int, wb_dat_i, wb_dat_o, wb_dat8_i, wb_dat8_o, wb_dat32_o, wb_sel_i,
we_o, re_o // Write and read enable output for the core
);

input clk;

// WISHBONE interface
input wb_rst_i;
input wb_we_i;
input wb_stb_i;
input wb_cyc_i;
input [3:0] wb_sel_i;
input [2:0] wb_adr_i; //WISHBONE address line

input [7:0] wb_dat_i; //input WISHBONE bus
output [7:0] wb_dat_o;
reg [7:0] wb_dat_o;
wire [7:0] wb_dat_i;
reg [7:0] wb_dat_is;

output [2:0] wb_adr_int; // internal signal for address bus
input [7:0] wb_dat8_o; // internal 8 bit output to be put into wb_dat_o
output [7:0] wb_dat8_i;
input [31:0] wb_dat32_o; // 32 bit data output (for debug interface)
output wb_ack_o;
output we_o;
output re_o;

wire we_o;
reg wb_ack_o;
reg [7:0] wb_dat8_i;
wire [7:0] wb_dat8_o;
wire [2:0] wb_adr_int; // internal signal for address bus
reg [2:0] wb_adr_is;
reg wb_we_is;
reg wb_cyc_is;
reg wb_stb_is;
wire [3:0] wb_sel_i;
reg wre ;// timing control signal for write or read enable

// wb_ack_o FSM
reg [1:0] wbstate;
always @(posedge clk or posedge wb_rst_i)
if (wb_rst_i) begin
wb_ack_o <= 1'b0;
wbstate <= 0;
wre <= 1'b1;
end else
case (wbstate)
0: begin
if (wb_stb_is & wb_cyc_is) begin
wre <= 0;
wbstate <= 1;
wb_ack_o <= 1;
end else begin
wre <= 1;
wb_ack_o <= 0;
end
end
1: begin
wb_ack_o <= 0;
wbstate <= 2;
wre <= 0;
end
2: begin
wb_ack_o <= 0;
wbstate <= 3;
wre <= 0;
end
3: begin
wb_ack_o <= 0;
wbstate <= 0;
wre <= 1;
end
endcase

assign we_o = wb_we_is & wb_stb_is & wb_cyc_is & wre ; //WE for registers
assign re_o = ~wb_we_is & wb_stb_is & wb_cyc_is & wre ; //RE for registers

// Sample input signals
always @(posedge clk or posedge wb_rst_i)
if (wb_rst_i) begin
wb_adr_is <= 0;
wb_we_is <= 0;
wb_cyc_is <= 0;
wb_stb_is <= 0;
wb_dat_is <= 0;
end else begin
wb_adr_is <= wb_adr_i;
wb_we_is <= wb_we_i;
wb_cyc_is <= wb_cyc_i;
wb_stb_is <= wb_stb_i;
wb_dat_is <= wb_dat_i;
end

always @(posedge clk or posedge wb_rst_i)
if (wb_rst_i)
wb_dat_o <= 0;
else
wb_dat_o <= wb_dat8_o;

always @(wb_dat_is)
wb_dat8_i = wb_dat_is;

assign wb_adr_int = wb_adr_is;


endmodule










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