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updated presets

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Steven Hugg 2018-01-13 14:48:58 -06:00
parent 45756f682d
commit a456f3d9cf
1 changed files with 28 additions and 25 deletions
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53
presets/verilog/hvsync_generator.v
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@ -2,55 +2,58 @@
`define HVSYNC_GENERATOR_H
module hvsync_generator(
clk, reset, hsync, vsync, display_on, hpos, vpos);
input clk;
input reset;
output reg hsync, vsync;
output reg display_on;
output reg [8:0] hpos;
output reg [8:0] vpos;
input clk,
input reset,
output hsync, vsync,
output display_on,
output [8:0] hpos,
output [8:0] vpos
);
// constant declarations for TV-simulator sync parameters
localparam H_DISPLAY = 256; // horizontal display area
localparam H_L_BORDER = 23; // horizontal left border (back porch)
localparam H_R_BORDER = 7; // horizontal right border (front porch)
localparam H_RETRACE = 23; // horizontal retrace (sync)
localparam H_MAX = H_DISPLAY + H_L_BORDER + H_R_BORDER + H_RETRACE - 1;
localparam START_H_RETRACE = H_DISPLAY + H_R_BORDER;
localparam END_H_RETRACE = H_DISPLAY + H_R_BORDER + H_RETRACE - 1;
localparam H_DISPLAY = 256; // horizontal display width
localparam H_BACK = 23; // horizontal left border (back porch)
localparam H_FRONT = 7; // horizontal right border (front porch)
localparam H_SYNC = 23; // horizontal sync width
localparam H_SYNC_START = H_DISPLAY + H_FRONT;
localparam H_SYNC_END = H_DISPLAY + H_FRONT + H_SYNC - 1;
localparam H_MAX = H_DISPLAY + H_BACK + H_FRONT + H_SYNC - 1;
localparam V_DISPLAY = 240; // vertical display area
localparam V_T_BORDER = 4; // vertical top border
localparam V_B_BORDER = 14; // vertical bottom border
localparam V_RETRACE = 4; // vertical retrace (sync)
localparam V_MAX = V_DISPLAY + V_T_BORDER + V_B_BORDER + V_RETRACE - 1;
localparam START_V_RETRACE = V_DISPLAY + V_B_BORDER;
localparam END_V_RETRACE = V_DISPLAY + V_B_BORDER + V_RETRACE - 1;
localparam V_DISPLAY = 240; // vertical display height
localparam V_TOP = 5; // vertical top border
localparam V_BOTTOM = 14; // vertical bottom border
localparam V_SYNC = 3; // vertical sync # lines
localparam V_SYNC_START = V_DISPLAY + V_BOTTOM;
localparam V_SYNC_END = V_DISPLAY + V_BOTTOM + V_SYNC - 1;
localparam V_MAX = V_DISPLAY + V_TOP + V_BOTTOM + V_SYNC - 1;
wire hmaxxed = (hpos == H_MAX) || reset;
wire vmaxxed = (vpos == V_MAX) || reset;
// increment horizontal position counter
always @(posedge clk)
begin
if(hmaxxed)
hpos <= 0;
else
hpos <= hpos + 1;
end;
// increment vertical position counter
always @(posedge clk)
begin
if(hmaxxed)
if (!vmaxxed)
vpos <= vpos + 1;
else
vpos <= 0;
end;
// compute hsync + vsync + display_on signals
always @(posedge clk)
begin
hsync <= (hpos>=START_H_RETRACE && hpos<=END_H_RETRACE);
vsync <= (vpos==START_V_RETRACE);
hsync <= (hpos>=H_SYNC_START && hpos<=H_SYNC_END);
vsync <= (vpos>=V_SYNC_START && vpos<=V_SYNC_END);
display_on <= (hpos<H_DISPLAY) && (vpos<V_DISPLAY);
end