Delete uart_transmitter.v
This commit is contained in:
parent
7345ca579f
commit
ef6e473216
|
@ -1,354 +0,0 @@
|
|||
//////////////////////////////////////////////////////////////////////
|
||||
//// ////
|
||||
//// 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
|
Loading…
Reference in New Issue