zcy
/
pluto_hdl_adi
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

util_pulse_gen: Reload registers when counter is at one 

This patch fixes an issue where the pulse width is only updated two
periods after the current one.

Signed-off-by: David Winter <david.winter@analog.com>
main
David Winter 2021-12-22 17:09:40 +01:00 committed by Laszlo Nagy
parent 6dddaaaa78
commit fcd3bfd349
1 changed files with 4 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

11
library/common/util_pulse_gen.v
View File

@ -58,8 +58,6 @@ module util_pulse_gen #(
reg [31:0] pulse_period_d = 32'b0; reg [31:0] pulse_period_d = 32'b0;
reg [31:0] pulse_width_d = 32'b0; reg [31:0] pulse_width_d = 32'b0;
wire end_of_period_s;
// flop the desired period // flop the desired period
always @(posedge clk) begin always @(posedge clk) begin
@ -75,7 +73,7 @@ module util_pulse_gen #(
pulse_width_read <= pulse_width; pulse_width_read <= pulse_width;
end end
// update the current period/width at the end of the period // update the current period/width at the end of the period
if (end_of_period_s) begin if (pulse_period_cnt == 32'h1) begin
pulse_period_d <= pulse_period_read; pulse_period_d <= pulse_period_read;
pulse_width_d <= pulse_width_read; pulse_width_d <= pulse_width_read;
end end
@ -85,18 +83,17 @@ module util_pulse_gen #(
// a free running counter // a free running counter
always @(posedge clk) begin always @(posedge clk) begin
if (pulse_period_cnt == 1'b0) begin if (pulse_period_cnt == 'b0) begin
pulse_period_cnt <= pulse_period_d; pulse_period_cnt <= pulse_period_d;
end else begin end else begin
pulse_period_cnt <= pulse_period_cnt - 1'b1; pulse_period_cnt <= pulse_period_cnt - 32'b1;
end end
end end
assign end_of_period_s = (pulse_period_cnt == 32'b0) ? 1'b1 : 1'b0;
// generate pulse with a specified width // generate pulse with a specified width
always @ (posedge clk) begin always @ (posedge clk) begin
if ((end_of_period_s == 1'b1) || (rstn == 1'b0)) begin if ((pulse_period_cnt == 'h0) || (rstn == 1'b0)) begin
pulse <= 1'b0; pulse <= 1'b0;
end else if (pulse_period_cnt == pulse_width_d) begin end else if (pulse_period_cnt == pulse_width_d) begin
pulse <= 1'b1; pulse <= 1'b1;