fix gs glitches with contended timings

This commit is contained in:
Eugene Lozovoy
2022-12-18 14:30:19 +03:00
parent bd57e87d4f
commit 4fe3fd7606
2 changed files with 20 additions and 6 deletions

View File

@ -75,6 +75,12 @@ always @(negedge clk32 or negedge rst_n) begin
rom_m1_access <= a[15:14] == 2'b00;
end
reg n_rd_wr_delayed, n_rd_wr_delayed1;
always @(posedge clk32) begin
n_rd_wr_delayed <= n_rd_wr_delayed1;
n_rd_wr_delayed1 <= n_wr & n_rd;
end
/* CONFIGURATION */
wire ym_ena = cfg[0];
@ -221,20 +227,28 @@ wire gs_dac3_wr = gs_dac3_cs && ~n_grd;
reg gs_flag_cmd, gs_flag_data;
wire [7:0] gs_status = {gs_flag_data, 6'b111111, gs_flag_cmd};
always @(posedge clk32) begin
if ((~n_giorq && n_gm1 && ga[3:0] == 4'h2) || (ioreq_rd && port_b3))
always @(posedge clk32 or negedge rst_n) begin
if (!rst_n)
gs_flag_data <= 1'b0;
else if ((~n_giorq && n_gm1 && ga[3:0] == 4'h3) || (ioreq_wr && port_b3))
else if (~n_iorq && ~n_rd && n_rd_wr_delayed && port_b3)
gs_flag_data <= 1'b0;
else if (~n_iorq && ~n_wr && n_rd_wr_delayed && port_b3)
gs_flag_data <= 1'b1;
else if (~n_giorq && n_gm1 && ga[3:0] == 4'h2)
gs_flag_data <= 1'b0;
else if (~n_giorq && n_gm1 && ga[3:0] == 4'h3)
gs_flag_data <= 1'b1;
else if (~n_giorq && n_gm1 && ga[3:0] == 4'hA)
gs_flag_data <= ~gs_reg00[0];
end
always @(posedge clk32) begin
if (~n_giorq && n_gm1 && ga[3:0] == 4'h5)
always @(posedge clk32 or negedge rst_n) begin
if (!rst_n)
gs_flag_cmd <= 1'b0;
else if (ioreq_wr && port_bb)
else if (~n_iorq && ~n_wr && n_rd_wr_delayed && port_bb)
gs_flag_cmd <= 1'b1;
else if (~n_giorq && n_gm1 && ga[3:0] == 4'h5)
gs_flag_cmd <= 1'b0;
else if (~n_giorq && n_gm1 && ga[3:0] == 4'hB)
gs_flag_cmd <= vol3[5];
end