请问如何通过FPGA驱动VGA显示一个圆形
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利用圆的方程X^2+Y^2<=z^2.x是行扫描计数值与圆心的差，y是列扫描与圆心的差。这是你要的圆的半径。我给你贴一段程序，我自己写的12个圆环，分了四个象限，比较蠢。不分象限的话要用无符号数。library ieee;use ieee.std_logic_1164.all;use ieee.std_logic_unsigned.all;entity vga_block isport (clk_40mhz:in std_logic; forming:in integer range 0 to 3; coulour:in integer range 0 to 2; h_or_f:in integer range 0 to 1;vga_out:out std_logic_vector(2 downto 0);hs1,vs1:out std_logic);end;architecture behave of vga_block issignal counter_hs:integer range 0 to 1055; --屏幕中行信号 HS 使用范围signal counter_vs:integer range 0 to 627; --屏幕中场信号 VS 使用范围signal hs,vs:std_logic:='1'; --行信号 hs 和场信号 vs 高电平signal rgb1,rgb2,rgb3:std_logic_vector(2 downto 0); --水平和垂直方向上表示 3 基色的中间变量signal coulour1,coulour2: std_logic_vector(2 downto 0);beginprocess(clk_40mhz) --40MHZ 触发在每行上逐点扫描beginif rising_edge(clk_40mhz) then if counter_hs>=1055 then counter_hs<=0;else counter_hs<=counter_hs+1;end if;end if;end process;process(counter_hs) --行消隐beginif counter_hs>=0 and counter_hs<128 thenhs<='0';elsehs<='1';end if;end process;process(hs)beginif falling_edge(hs) then --VGA 中行同步负脉冲有效if counter_vs>=627 thencounter_vs<=0;else counter_vs<=counter_vs+1; --垂直扫描end if;end if;end process;process(counter_vs) --场消隐beginif counter_vs>=0 and counter_vs<=3 thenvs<='0';elsevs<='1';end if;end process;
process(counter_hs,counter_vs）
if (counter_hs >=216 and counter_hs <=616) then if (counter_vs >=27 and counter_vs <=327) then if (((327-counter_vs)**2+(616-counter_hs)**2) <=90000 and ((327-counter_vs)**2+(616-counter_hs)**2) >=75625)or(((327-counter_vs)**2+(616-counter_hs)**2) < 62500 and ((327-counter_vs)**2+(616-counter_hs)**2) >=50625)or(((327-counter_vs)**2+(616-counter_hs)**2) < 40000 and ((327-counter_vs)**2+(616-counter_hs)**2) >=30625)or(((327-counter_vs)**2+(616-counter_hs)**2) < 22500 and ((327-counter_vs)**2+(616-counter_hs)**2) >=15625)or(((327-counter_vs)**2+(616-counter_hs)**2) < 10000 and ((327-counter_vs)**2+(616-counter_hs)**2) >=5625)or(((327-counter_vs)**2+(616-counter_hs)**2) < 2500 and ((327-counter_vs)**2+(616-counter_hs)**2) >=625) then rgb1 <=coulour1; elsif (((327-counter_vs)**2+(616-counter_hs)**2) < 75625 and ((327-counter_vs)**2+(616-counter_hs)**2) >=62500)or(((327-counter_vs)**2+(616-counter_hs)**2) < 50625 and ((327-counter_vs)**2+(616-counter_hs)**2) >=40000)or(((327-counter_vs)**2+(616-counter_hs)**2) < 30625 and ((327-counter_vs)**2+(616-counter_hs)**2) >=22500)or(((327-counter_vs)**2+(616-counter_hs)**2) < 15625 and ((327-counter_vs)**2+(616-counter_hs)**2) >=10000)or(((327-counter_vs)**2+(616-counter_hs)**2) < 5625 and ((327-counter_vs)**2+(616-counter_hs)**2) >=2500)or(((327-counter_vs)**2+(616-counter_hs)**2) < 625 and ((327-counter_vs)**2+(616-counter_hs)**2) >=0) then rgb1 <=coulour2;else rgb1 <="000";end if; elsif (counter_vs >=327 and counter_vs <=627) then if (((counter_vs-327)**2+(616-counter_hs)**2) <=90000 and ((counter_vs-327)**2+(616-counter_hs)**2) >=75625)or(((counter_vs-327)**2+(616-counter_hs)**2) < 62500 and ((counter_vs-327)**2+(616-counter_hs)**2) >=50625)or(((counter_vs-327)**2+(616-counter_hs)**2) < 40000 and ((counter_vs-327)**2+(616-counter_hs)**2) >=30625)or(((counter_vs-327)**2+(616-counter_hs)**2) < 22500 and ((counter_vs-327)**2+(616-counter_hs)**2) >=15625)or(((counter_vs-327)**2+(616-counter_hs)**2) < 10000 and ((counter_vs-327)**2+(616-counter_hs)**2) >=5625)or(((counter_vs-327)**2+(616-counter_hs)**2) < 2500 and ((counter_vs-327)**2+(616-counter_hs)**2) >=625) then rgb1 <=coulour1; elsif (((counter_vs-327)**2+(616-counter_hs)**2) < 75625 and ((counter_vs-327)**2+(616-counter_hs)**2) >=62500)or(((counter_vs-327)**2+(616-counter_hs)**2) < 50625 and ((counter_vs-327)**2+(616-counter_hs)**2) >=40000)or(((counter_vs-327)**2+(616-counter_hs)**2) < 30625 and ((counter_vs-327)**2+(616-counter_hs)**2) >=22500)or(((counter_vs-327)**2+(616-counter_hs)**2) < 15625 and ((counter_vs-327)**2+(616-counter_hs)**2) >=10000)or(((counter_vs-327)**2+(616-counter_hs)**2) < 5625 and ((counter_vs-327)**2+(616-counter_hs)**2) >=2500)or(((counter_vs-327)**2+(616-counter_hs)**2) < 625 and ((counter_vs-327)**2+(616-counter_hs)**2) >=0) then rgb1 <=coulour2;else rgb1 <="000";end if; end if; elsif (counter_hs >=616 and counter_hs <=1016) then if (counter_vs >=27 and counter_vs <=327) then if (((327-counter_vs)**2+(counter_hs-616)**2) <=90000 and ((327-counter_vs)**2+(counter_hs-616)**2) >=75625)or(((327-counter_vs)**2+(counter_hs-616)**2) < 62500 and ((327-counter_vs)**2+(counter_hs-616)**2) >=50625)or(((327-counter_vs)**2+(counter_hs-616)**2) < 40000 and ((327-counter_vs)**2+(counter_hs-616)**2) >=30625)or(((327-counter_vs)**2+(counter_hs-616)**2) < 22500 and ((327-counter_vs)**2+(counter_hs-616)**2) >=15625)or(((327-counter_vs)**2+(counter_hs-616)**2) < 10000 and ((327-counter_vs)**2+(counter_hs-616)**2) >=5625)or(((327-counter_vs)**2+(counter_hs-616)**2) < 2500 and ((327-counter_vs)**2+(counter_hs-616)**2) >=625) then rgb1 <=coulour1; elsif (((327-counter_vs)**2+(counter_hs-616)**2) < 75625 and ((327-counter_vs)**2+(counter_hs-616)**2) >=62500)or(((327-counter_vs)**2+(counter_hs-616)**2) < 50625 and ((327-counter_vs)**2+(counter_hs-616)**2) >=40000)or(((327-counter_vs)**2+(counter_hs-616)**2) < 30625 and ((327-counter_vs)**2+(counter_hs-616)**2) >=22500)or(((327-counter_vs)**2+(counter_hs-616)**2) < 15625 and ((327-counter_vs)**2+(counter_hs-616)**2) >=10000)or(((327-counter_vs)**2+(counter_hs-616)**2) < 5625 and ((327-counter_vs)**2+(counter_hs-616)**2) >=2500)or(((327-counter_vs)**2+(counter_hs-616)**2) < 625 and ((327-counter_vs)**2+(counter_hs-616)**2) >=0) then rgb1 <=coulour2;else rgb1 <="000";end if; elsif (counter_vs >=327 and counter_vs <=627) then if (((counter_vs-327)**2+(counter_hs-616)**2) <=90000 and ((counter_vs-327)**2+(counter_hs-616)**2) >=75625)or(((counter_vs-327)**2+(counter_hs-616)**2) < 62500 and ((counter_vs-327)**2+(counter_hs-616)**2) >=50625)or(((counter_vs-327)**2+(counter_hs-616)**2) < 40000 and ((counter_vs-327)**2+(counter_hs-616)**2) >=30625)or(((counter_vs-327)**2+(counter_hs-616)**2) < 22500 and ((counter_vs-327)**2+(counter_hs-616)**2) >=15625)or(((counter_vs-327)**2+(counter_hs-616)**2) < 10000 and ((counter_vs-327)**2+(counter_hs-616)**2) >=5625)or(((counter_vs-327)**2+(counter_hs-616)**2) < 2500 and ((counter_vs-327)**2+(counter_hs-616)**2) >=625) then rgb1 <=coulour1; elsif (((counter_vs-327)**2+(counter_hs-616)**2) < 75625 and ((counter_vs-327)**2+(counter_hs-616)**2) >=62500)or(((counter_vs-327)**2+(counter_hs-616)**2) < 50625 and ((counter_vs-327)**2+(counter_hs-616)**2) >=40000)or(((counter_vs-327)**2+(counter_hs-616)**2) < 30625 and ((counter_vs-327)**2+(counter_hs-616)**2) >=22500)or(((counter_vs-327)**2+(counter_hs-616)**2) < 15625 and ((counter_vs-327)**2+(counter_hs-616)**2) >=10000)or(((counter_vs-327)**2+(counter_hs-616)**2) < 5625 and ((counter_vs-327)**2+(counter_hs-616)**2) >=2500)or(((counter_vs-327)**2+(counter_hs-616)**2) < 625 and ((counter_vs-327)**2+(counter_hs-616)**2) >=0) then rgb1 <=coulour2;else rgb1 <="000";end if; end if; end if;--圆环
hs1 <= hs;vs1 <= vs;Vga_out<=rgb1 end process;end; 参考技术A VGA显示器是模拟的三基色输入，所以用FPGA驱动的话，首先要三个D/A转换器，当然如果只是显示一个圆形，FPGA用I/O口外搞几个电阻也是可以实现显示一个只有几种颜色的圆形。不知道你的具体要求，如果有实验箱什么的，一般上面应该有D/A转换器，而且有VGA接口，只要正确驱动就可以了。那你再具体描述一下你的要求？
FPGA的学习：HDMI显示器驱动设计与验证
HDMI的顶层模块设计如图所示：
其中包含了一个时钟产生电路，vga_pic模块，vga_ctrl模块，hdmi_ctrl模块。
各个模块的设计图如下：
其中还要用到一个encode模块：
还要用到par_to_ser以及ddio_out模块：
接下来是encode模块的实现：
`timescale 1ns/1ns
module encode
(
input wire sys_clk , //时钟信号
input wire sys_rst_n , //复位信号,低有效
input wire [7:0] data_in , //输入8bit待编码数据
input wire c0 , //控制信号c0
input wire c1 , //控制信号c1
input wire de , //使能信号
output reg [9:0] data_out //输出编码后的10bit数据
);
//parameter define
parameter DATA_OUT0 = 10'b1101010100,
DATA_OUT1 = 10'b0010101011,
DATA_OUT2 = 10'b0101010100,
DATA_OUT3 = 10'b1010101011;
//wire define
wire condition_1 ; //条件1
wire condition_2 ; //条件2
wire condition_3 ; //条件3
wire [8:0] q_m ; //第一阶段转换后的9bit数据
//reg define
reg [3:0] data_in_n1 ; //待编码数据中1的个数
reg [7:0] data_in_reg ; //待编码数据打一拍
reg [3:0] q_m_n1 ; //转换后9bit数据中1的个数
reg [3:0] q_m_n0 ; //转换后9bit数据中0的个数
reg [4:0] cnt ; //视差计数器,0-1个数差别,最高位为符号位
reg de_reg1 ; //使能信号打一拍
reg de_reg2 ; //使能信号打两拍
reg c0_reg1 ; //控制信号c0打一拍
reg c0_reg2 ; //控制信号c0打两拍
reg c1_reg1 ; //控制信号c1打一拍
reg c1_reg2 ; //控制信号c1打两拍
reg [8:0] q_m_reg ; //q_m信号打一拍
//********************************************************************//
//***************************** Main Code ****************************//
//********************************************************************//
//data_in_n1:待编码数据中1的个数
always@(posedge sys_clk or negedge sys_rst_n)
if(sys_rst_n == 1'b0)
data_in_n1 <= 4'd0;
else
data_in_n1 <= data_in[0] + data_in[1] + data_in[2]
+ data_in[3] + data_in[4] + data_in[5]
+ data_in[6] + data_in[7];
//data_in_reg:待编码数据打一拍
always@(posedge sys_clk or negedge sys_rst_n)
if(sys_rst_n == 1'b0)
data_in_reg <= 8'b0;
else
data_in_reg <= data_in;
//condition_1:条件1
assign condition_1 = ((data_in_n1 > 4'd4) || ((data_in_n1 == 4'd4)
&& (data_in_reg[0] == 1'b0)));
//q_m:第一阶段转换后的9bit数据
assign q_m[0] = data_in_reg[0];
assign q_m[1] = (condition_1) ? (q_m[0] ^~ data_in_reg[1]) : (q_m[0] ^ data_in_reg[1]);
assign q_m[2] = (condition_1) ? (q_m[1] ^~ data_in_reg[2]) : (q_m[1] ^ data_in_reg[2]);
assign q_m[3] = (condition_1) ? (q_m[2] ^~ data_in_reg[3]) : (q_m[2] ^ data_in_reg[3]);
assign q_m[4] = (condition_1) ? (q_m[3] ^~ data_in_reg[4]) : (q_m[3] ^ data_in_reg[4]);
assign q_m[5] = (condition_1) ? (q_m[4] ^~ data_in_reg[5]) : (q_m[4] ^ data_in_reg[5]);
assign q_m[6] = (condition_1) ? (q_m[5] ^~ data_in_reg[6]) : (q_m[5] ^ data_in_reg[6]);
assign q_m[7] = (condition_1) ? (q_m[6] ^~ data_in_reg[7]) : (q_m[6] ^ data_in_reg[7]);
assign q_m[8] = (condition_1) ? 1'b0 : 1'b1;
//q_m_n1:转换后9bit数据中1的个数
//q_m_n0:转换后9bit数据中0的个数
always@(posedge sys_clk or negedge sys_rst_n)
if(sys_rst_n == 1'b0)
begin
q_m_n1 <= 4'd0;
q_m_n0 <= 4'd0;
end
else
begin
q_m_n1 <= q_m[0] + q_m[1] + q_m[2] + q_m[3] + q_m[4] + q_m[5] + q_m[6] + q_m[7];
q_m_n0 <= 4'd8 - (q_m[0] + q_m[1] + q_m[2] + q_m[3] + q_m[4] + q_m[5] + q_m[6] + q_m[7]);
end
//condition_2:条件2
assign condition_2 = ((cnt == 5'd0) || (q_m_n1 == q_m_n0));
//condition_3:条件3
assign condition_3 = (((~cnt[4] == 1'b1) && (q_m_n1 > q_m_n0))
|| ((cnt[4] == 1'b1) && (q_m_n0 > q_m_n1)));
//数据打拍,为了各数据同步
always@(posedge sys_clk or negedge sys_rst_n)
if(sys_rst_n == 1'b0)
begin
de_reg1 <= 1'b0;
de_reg2 <= 1'b0;
c0_reg1 <= 1'b0;
c0_reg2 <= 1'b0;
c1_reg1 <= 1'b0;
c1_reg2 <= 1'b0;
q_m_reg <= 9'b0;
end
else
begin
de_reg1 <= de;
de_reg2 <= de_reg1;
c0_reg1 <= c0;
c0_reg2 <= c0_reg1;
c1_reg1 <= c1;
c1_reg2 <= c1_reg1;
q_m_reg <= q_m;
end
//data_out:输出编码后的10bit数据
//cnt:视差计数器,0-1个数差别,最高位为符号位
always@(posedge sys_clk or negedge sys_rst_n)
if(sys_rst_n == 1'b0)
begin
data_out <= 10'b0;
cnt <= 5'b0;
end
else
begin
if(de_reg2 == 1'b1)
begin
if(condition_2 == 1'b1)
begin
data_out[9] <= ~q_m_reg[8];
data_out[8] <= q_m_reg[8];
data_out[7:0] <= (q_m_reg[8]) ? q_m_reg[7:0] : ~q_m_reg[7:0];
cnt <= (~q_m_reg[8]) ? (cnt + q_m_n0 - q_m_n1) : (cnt + q_m_n1 - q_m_n0);
end
else
begin
if(condition_3 == 1'b1)
begin
data_out[9] <= 1'b1;
data_out[8] <= q_m_reg[8];
data_out[7:0] <= ~q_m_reg[7:0];
cnt <= cnt + {q_m_reg[8], 1'b0} + (q_m_n0 - q_m_n1);
end
else
begin
data_out[9] <= 1'b0;
data_out[8] <= q_m_reg[8];
data_out[7:0] <= q_m_reg[7:0];
cnt <= cnt - {~q_m_reg[8], 1'b0} + (q_m_n1 - q_m_n0);
end
end
end
else
begin
case ({c1_reg2, c0_reg2})
2'b00: data_out <= DATA_OUT0;
2'b01: data_out <= DATA_OUT1;
2'b10: data_out <= DATA_OUT2;
default:data_out <= DATA_OUT3;
endcase
cnt <= 5'b0;
end
end
endmodule
par_to_ser模块的实现如下：
`timescale 1ns/1ns
module par_to_ser
(
input wire clk_5x , //输入系统时钟
input wire [9:0] par_data , //输入并行数据
output wire ser_data_p , //输出串行差分数据
output wire ser_data_n //输出串行差分数据
);
//********************************************************************//
//****************** Parameter and Internal Signal *******************//
//********************************************************************//
//wire define
wire [4:0] data_rise = {par_data[8],par_data[6],
par_data[4],par_data[2],par_data[0]};
wire [4:0] data_fall = {par_data[9],par_data[7],
par_data[5],par_data[3],par_data[1]};
//reg define
reg [4:0] data_rise_s = 0;
reg [4:0] data_fall_s = 0;
reg [2:0] cnt = 0;
always @ (posedge clk_5x)
begin
cnt <= (cnt[2]) ? 3'd0 : cnt + 3'd1;
data_rise_s <= cnt[2] ? data_rise : data_rise_s[4:1];
data_fall_s <= cnt[2] ? data_fall : data_fall_s[4:1];
end
//********************************************************************//
//**************************** Instantiate ***************************//
//********************************************************************//
//------------- ddio_out_inst0 -------------
ddio_out ddio_out_inst0
(
.datain_h (data_rise_s[0] ),
.datain_l (data_fall_s[0] ),
.outclock (~clk_5x ),
.dataout (ser_data_p )
);
//------------- ddio_out_inst1 -------------
ddio_out ddio_out_inst1
(
.datain_h (~data_rise_s[0]),
.datain_l (~data_fall_s[0]),
.outclock (~clk_5x ),
.dataout (ser_data_n )
);
endmodule
HDMI控制模块如下：
`timescale 1ns/1ns
module hdmi_ctrl
(
input wire clk_1x , //输入系统时钟
input wire clk_5x , //输入5倍系统时钟
input wire sys_rst_n , //复位信号,低有效
input wire [7:0] rgb_blue , //蓝色分量
input wire [7:0] rgb_green , //绿色分量
input wire [7:0] rgb_red , //红色分量
input wire hsync , //行同步信号
input wire vsync , //场同步信号
input wire de , //使能信号
output wire hdmi_clk_p ,
output wire hdmi_clk_n , //时钟差分信号
output wire hdmi_r_p ,
output wire hdmi_r_n , //红色分量差分信号
output wire hdmi_g_p ,
output wire hdmi_g_n , //绿色分量差分信号
output wire hdmi_b_p ,
output wire hdmi_b_n //蓝色分量差分信号
);
//********************************************************************//
//****************** Parameter and Internal Signal *******************//
//********************************************************************//
wire [9:0] red ; //8b转10b后的红色分量
wire [9:0] green ; //8b转10b后的绿色分量
wire [9:0] blue ; //8b转10b后的蓝色分量
//********************************************************************//
//**************************** Instantiate ***************************//
//********************************************************************//
//------------- encode_inst0 -------------
encode encode_inst0
(
.sys_clk (clk_1x ),
.sys_rst_n (sys_rst_n ),
.data_in (rgb_blue ),
.c0 (hsync ),
.c1 (vsync ),
.de (de ),
.data_out (blue )
);
//------------- encode_inst1 -------------
encode encode_inst1
(
.sys_clk (clk_1x ),
.sys_rst_n (sys_rst_n ),
.data_in (rgb_green ),
.c0 (hsync ),
.c1 (vsync ),
.de (de ),
.data_out (green )
);
//------------- encode_inst2 -------------
encode encode_inst2
(
.sys_clk (clk_1x ),
.sys_rst_n (sys_rst_n ),
.data_in (rgb_red ),
.c0 (hsync ),
.c1 (vsync ),
.de (de ),
.data_out (red )
);
//------------- par_to_ser_inst0 -------------
par_to_ser par_to_ser_inst0
(
.clk_5x (clk_5x ),
.par_data (blue ),
.ser_data_p (hdmi_b_p ),
.ser_data_n (hdmi_b_n )
);
//------------- par_to_ser_inst1 -------------
par_to_ser par_to_ser_inst1
(
.clk_5x (clk_5x ),
.par_data (green ),
.ser_data_p (hdmi_g_p ),
.ser_data_n (hdmi_g_n )
);
//------------- par_to_ser_inst2 -------------
par_to_ser par_to_ser_inst2
(
.clk_5x (clk_5x ),
.par_data (red ),
.ser_data_p (hdmi_r_p ),
.ser_data_n (hdmi_r_n )
);
//------------- par_to_ser_inst3 -------------
par_to_ser par_to_ser_inst3
(
.clk_5x (clk_5x ),
.par_data (10'b1111100000),
.ser_data_p (hdmi_clk_p ),
.ser_data_n (hdmi_clk_n )
);
endmodule
vga_ctrl和vga_pic模块分别如下：
`timescale 1ns/1ns
module vga_ctrl
(
input wire vga_clk , //输入工作时钟,频率25MHz
input wire sys_rst_n , //输入复位信号,低电平有效
input wire [15:0] pix_data , //输入像素点色彩信息
output wire [11:0] pix_x , //输出VGA有效显示区域像素点X轴坐标
output wire [11:0] pix_y , //输出VGA有效显示区域像素点Y轴坐标
output wire hsync , //输出行同步信号
output wire vsync , //输出场同步信号
output wire rgb_valid ,
output wire [15:0] rgb //输出像素点色彩信息
);
//********************************************************************//
//****************** Parameter and Internal Signal *******************//
//********************************************************************//
//parameter define
parameter H_SYNC = 10'd96 , //行同步
H_BACK = 10'd40 , //行时序后沿
H_LEFT = 10'd8 , //行时序左边框
H_VALID = 10'd640 , //行有效数据
H_RIGHT = 10'd8 , //行时序右边框
H_FRONT = 10'd8 , //行时序前沿
H_TOTAL = 10'd800 ; //行扫描周期
parameter V_SYNC = 10'd2 , //场同步
V_BACK = 10'd25 , //场时序后沿
V_TOP = 10'd8 , //场时序上边框
V_VALID = 10'd480 , //场有效数据
V_BOTTOM = 10'd8 , //场时序下边框
V_FRONT = 10'd2 , //场时序前沿
V_TOTAL = 10'd525 ; //场扫描周期
//wire define
wire pix_data_req ; //像素点色彩信息请求信号
//reg define
reg [11:0] cnt_h ; //行同步信号计数器
reg [11:0] cnt_v ; //场同步信号计数器
//********************************************************************//
//***************************** Main Code ****************************//
//********************************************************************//
//cnt_h:行同步信号计数器
always@(posedge vga_clk or negedge sys_rst_n)
if(sys_rst_n == 1'b0)
cnt_h <= 12'd0 ;
else if(cnt_h == H_TOTAL - 1'd1)
cnt_h <= 12'd0 ;
else
cnt_h <= cnt_h + 1'd1 ;
//hsync:行同步信号
assign hsync = (cnt_h <= H_SYNC - 1'd1) ? 1'b1 : 1'b0 ;
//cnt_v:场同步信号计数器
always@(posedge vga_clk or negedge sys_rst_n)
if(sys_rst_n == 1'b0)
cnt_v <= 12'd0 ;
else if((cnt_v == V_TOTAL - 1'd1) && (cnt_h == H_TOTAL-1'd1))
cnt_v <= 12'd0 ;
else if(cnt_h == H_TOTAL - 1'd1)
cnt_v <= cnt_v + 1'd1 ;
else
cnt_v <= cnt_v ;
//vsync:场同步信号
assign vsync = (cnt_v <= V_SYNC - 1'd1) ? 1'b1 : 1'b0 ;
//rgb_valid:VGA有效显示区域
assign rgb_valid = (((cnt_h >= H_SYNC + H_BACK + H_LEFT)
&& (cnt_h < H_SYNC + H_BACK + H_LEFT + H_VALID))
&&((cnt_v >= V_SYNC + V_BACK + V_TOP)
&& (cnt_v < V_SYNC + V_BACK + V_TOP + V_VALID)))
? 1'b1 : 1'b0;
//pix_data_req:像素点色彩信息请求信号,超前rgb_valid信号一个时钟周期
assign pix_data_req = (((cnt_h >= H_SYNC + H_BACK + H_LEFT - 1'b1)
&& (cnt_h < H_SYNC + H_BACK + H_LEFT + H_VALID - 1'b1))
&&((cnt_v >= V_SYNC + V_BACK + V_TOP)
&& (cnt_v < V_SYNC + V_BACK + V_TOP + V_VALID)))
? 1'b1 : 1'b0;
//pix_x,pix_y:VGA有效显示区域像素点坐标
assign pix_x = (pix_data_req == 1'b1)
? (cnt_h - (H_SYNC + H_BACK + H_LEFT - 1'b1)) : 12'hfff;
assign pix_y = (pix_data_req == 1'b1)
? (cnt_v - (V_SYNC + V_BACK + V_TOP)) : 12'hfff;
//rgb:输出像素点色彩信息
assign rgb = (rgb_valid == 1'b1) ? pix_data : 16'b0 ;
endmodule
`timescale 1ns/1ns
module vga_pic
(
input wire vga_clk , //输入工作时钟,频率25MHz
input wire sys_rst_n , //输入复位信号,低电平有效
input wire [11:0] pix_x , //输入VGA有效显示区域像素点X轴坐标
input wire [11:0] pix_y , //输入VGA有效显示区域像素点Y轴坐标
output reg [15:0] pix_data //输出像素点色彩信息
);
//********************************************************************//
//****************** Parameter and Internal Signal *******************//
//********************************************************************//
//parameter define
parameter H_VALID = 12'd640 , //行有效数据
V_VALID = 12'd480 ; //场有效数据
parameter RED = 16'hF800, //红色
ORANGE = 16'hFC00, //橙色
YELLOW = 16'hFFE0, //黄色
GREEN = 16'h07E0, //绿色
CYAN = 16'h07FF, //青色
BLUE = 16'h001F, //蓝色
PURPPLE = 16'hF81F, //紫色
BLACK = 16'h0000, //黑色
WHITE = 16'hFFFF, //白色
GRAY = 16'hD69A; //灰色
//********************************************************************//
//***************************** Main Code ****************************//
//********************************************************************//
//pix_data:输出像素点色彩信息,根据当前像素点坐标指定当前像素点颜色数据
always@(posedge vga_clk or negedge sys_rst_n)
if(sys_rst_n == 1'b0)
pix_data <= 16'd0;
else if((pix_x >= 0) && (pix_x < (H_VALID/10)*1))
pix_data <= RED;
else if((pix_x >= (H_VALID/10)*1) && (pix_x < (H_VALID/10)*2))
pix_data <= ORANGE;
else if((pix_x >= (H_VALID/10)*2) && (pix_x < (H_VALID/10)*3))
pix_data <= YELLOW;
else if((pix_x >= (H_VALID/10)*3) && (pix_x < (H_VALID/10)*4))
pix_data <= GREEN;
else if((pix_x >= (H_VALID/10)*4) && (pix_x < (H_VALID/10)*5))
pix_data <= CYAN;
else if((pix_x >= (H_VALID/10)*5) && (pix_x < (H_VALID/10)*6))
pix_data <= BLUE;
else if((pix_x >= (H_VALID/10)*6) && (pix_x < (H_VALID/10)*7))
pix_data <= PURPPLE;
else if((pix_x >= (H_VALID/10)*7) && (pix_x < (H_VALID/10)*8))
pix_data <= BLACK;
else if((pix_x >= (H_VALID/10)*8) && (pix_x < (H_VALID/10)*9))
pix_data <= WHITE;
else if((pix_x >= (H_VALID/10)*9) && (pix_x < H_VALID))
pix_data <= GRAY;
else
pix_data <= BLACK;
endmodule
最后是主程序的实现：
`timescale 1ns/1ns
module hdmi_colorbar
(
input wire sys_clk , //输入工作时钟,频率50MHz
input wire sys_rst_n , //输入复位信号,低电平有效
output wire ddc_scl ,
output wire ddc_sda ,
output wire tmds_clk_p ,
output wire tmds_clk_n , //HDMI时钟差分信号
output wire [2:0] tmds_data_p ,
output wire [2:0] tmds_data_n //HDMI图像差分信号
);
//********************************************************************//
//****************** Parameter and Internal Signal *******************//
//********************************************************************//
//wire define
wire vga_clk ; //VGA工作时钟,频率25MHz
wire clk_5x ;
wire locked ; //PLL locked信号
wire rst_n ; //VGA模块复位信号
wire [11:0] pix_x ; //VGA有效显示区域X轴坐标
wire [11:0] pix_y ; //VGA有效显示区域Y轴坐标
wire [15:0] pix_data; //VGA像素点色彩信息
wire hsync ; //输出行同步信号
wire vsync ; //输出场同步信号
wire [15:0] rgb ; //输出像素信息
wire rgb_valid;
//rst_n:VGA模块复位信号
assign rst_n = (sys_rst_n & locked);
assign ddc_scl = 1'b1;
assign ddc_sda = 1'b1;
//********************************************************************//
//*************************** Instantiation **************************//
//********************************************************************//
//------------- clk_gen_inst -------------
clk_gen clk_gen_inst
(
.areset (~sys_rst_n ), //输入复位信号,高电平有效,1bit
.inclk0 (sys_clk ), //输入50MHz晶振时钟,1bit
.c0 (vga_clk ), //输出VGA工作时钟,频率25Mhz,1bit
.c1 (clk_5x ),
.locked (locked ) //输出pll locked信号,1bit
);
//------------- vga_ctrl_inst -------------
vga_ctrl vga_ctrl_inst
(
.vga_clk (vga_clk ), //输入工作时钟,频率25MHz,1bit
.sys_rst_n (rst_n ), //输入复位信号,低电平有效,1bit
.pix_data (pix_data ), //输入像素点色彩信息,16bit
.pix_x (pix_x ), //输出VGA有效显示区域像素点X轴坐标,10bit
.pix_y (pix_y ), //输出VGA有效显示区域像素点Y轴坐标,10bit
.hsync (hsync ), //输出行同步信号,1bit
.vsync (vsync ), //输出场同步信号,1bit
.rgb_valid (rgb_valid ),
.rgb (rgb ) //输出像素点色彩信息,16bit
);
//------------- vga_pic_inst -------------
vga_pic vga_pic_inst
(
.vga_clk (vga_clk ), //输入工作时钟,频率25MHz,1bit
.sys_rst_n (rst_n ), //输入复位信号,低电平有效,1bit
.pix_x (pix_x ), //输入VGA有效显示区域像素点X轴坐标,10bit
.pix_y (pix_y ), //输入VGA有效显示区域像素点Y轴坐标,10bit
.pix_data (pix_data ) //输出像素点色彩信息,16bit
);
//------------- hdmi_ctrl_inst -------------
hdmi_ctrl hdmi_ctrl_inst
(
.clk_1x (vga_clk ), //输入系统时钟
.clk_5x (clk_5x ), //输入5倍系统时钟
.sys_rst_n (rst_n ), //复位信号,低有效
.rgb_blue ({rgb[4:0],3'b0} ), //蓝色分量
.rgb_green ({rgb[10:5],2'b0} ), //绿色分量
.rgb_red ({rgb[15:11],3'b0} ), //红色分量
.hsync (hsync ), //行同步信号
.vsync (vsync ), //场同步信号
.de (rgb_valid ), //使能信号
.hdmi_clk_p (tmds_clk_p ),
.hdmi_clk_n (tmds_clk_n ), //时钟差分信号
.hdmi_r_p (tmds_data_p[2] ),
.hdmi_r_n (tmds_data_n[2] ), //红色分量差分信号
.hdmi_g_p (tmds_data_p[1] ),
.hdmi_g_n (tmds_data_n[1] ), //绿色分量差分信号
.hdmi_b_p (tmds_data_p[0] ),
.hdmi_b_n (tmds_data_n[0] ) //蓝色分量差分信号
);
endmodule
进行仿真：
`timescale 1ns/1ns
module tb_hdmi_colorbar();
//********************************************************************//
//****************** Parameter and Internal Signal *******************//
//********************************************************************//
//wire define
wire ddc_scl ;
wire ddc_sda ;
wire tmds_clk_p ;
wire tmds_clk_n ;
wire [2:0] tmds_data_p ;
wire [2:0] tmds_data_n ;
//reg define
reg sys_clk ;
reg sys_rst_n ;
//********************************************************************//
//**************************** Clk And Rst ***************************//
//********************************************************************//
//sys_clk,sys_rst_n初始赋值
initial
begin
sys_clk = 1'b1;
sys_rst_n <= 1'b0;
#200
sys_rst_n <= 1'b1;
end
//sys_clk：产生时钟
always #10 sys_clk = ~sys_clk ;
//********************************************************************//
//*************************** Instantiation **************************//
//********************************************************************//
//------------- hdmi_colorbar_inst -------------
hdmi_colorbar hdmi_colorbar_inst
(
.sys_clk (sys_clk ), //输入工作时钟,频率50MHz
.sys_rst_n (sys_rst_n ), //输入复位信号,低电平有效
.ddc_scl (ddc_scl ),
.ddc_sda (ddc_sda ),
.tmds_clk_p (tmds_clk_p ),
.tmds_clk_n (tmds_clk_n ), //HDMI时钟差分信号
.tmds_data_p (tmds_data_p),
.tmds_data_n (tmds_data_n) //HDMI图像差分信号
);
endmodule
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