TFT显示屏驱动

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已经学习过VGA 时序与实现-CSDN博客

VGA 多分辨率-CSDN博客

今天就来让TFT屏显示一下

小梅哥视频：24 RGB TFT显示屏原理与驱动实现_哔哩哔哩_bilibili

1. 设置显示屏参数与时钟

注意到VGA_parameter.v中，不懂得分辨率对应于不同的频率，这里结合IP核，学习clk

现有时钟频率为50MHz ，5寸 TFT屏对应800*480为33MHz

采用PLL锁相环设置时钟频率

由于 ACZ702 的按键按下是低电平， PLL 复位设置成低电平有效。

具体设置方法如下：

本次实验只生成一个时钟频率，但在本页设置中，可以增加多个输出时钟：

同频率不同相位、不同频率等，在后续实验中，可以进行设置进行比较

本次未设置reset 、locked

2. VGA_CTRL.v

本程序中未对RGB888/RGB565进行设置

在xdc文件中进行说明

module VGA_CTRL(
                input clk ,
                input reset_n ,
                input [23:0]data ,
                output reg data_req ,
                output reg [11:0]H_addr , //当前扫描点的H坐标
                output reg [11:0]V_addr , //当前扫描点的V坐标
                output reg VGA_HS ,
                output reg VGA_VS , 
                output reg VGA_BLK , //BLK表示的是data时间段
                output reg [23:0]VGA_RGB  //{R[7:0]、G[7:0]、B[7:0]}
            );
    
    
    `include "vga_parameter.v"
     localparam VGA_HS_end = `H_Sync_Time - 1'b1 ;
     localparam Hdat_begin = `H_Sync_Time + `H_Back_Porch + `H_Left_Border - 1'b1 ;
     localparam Hdat_end = `H_Total_Time - `H_Right_Border - `H_Front_Porch - 1'b1 ;
     localparam Hpixel_end = `H_Total_Time - 1'b1 ;
     localparam VGA_VS_end = `V_Sync_Time - 1'b1 ;
     localparam Vdat_begin = `V_Sync_Time + `V_Back_Porch + `V_Top_Border - 1'b1 ;
     localparam Vdat_end = `V_Total_Time - `V_Bottom_Border - `V_Front_Porch - 1'b1 ;
     localparam Vline_end = `V_Total_Time - 1'b1 ;
    
   //行计数器
    reg[11:0]H_cnt;
    always@(posedge clk or negedge reset_n)
    if(!reset_n)    H_cnt <= 0 ;
    else if(H_cnt == Hpixel_end)
        H_cnt <= 0 ;
    else 
        H_cnt <= H_cnt + 1'b1 ;
    
    // 场计数器
    reg[11:0]V_cnt;
    always@(posedge clk or negedge reset_n)
    if(!reset_n)    V_cnt <= 0 ;
    else if(H_cnt == Hpixel_end)
        if(V_cnt == Vline_end)
            V_cnt <= 0 ;
        else 
            V_cnt <= V_cnt + 1'b1 ;
    else 
        V_cnt <= V_cnt ;
        
      //     VGA_HS
    always@(posedge clk or negedge reset_n)
    if(!reset_n)  VGA_HS <= 1;
    else if(H_cnt == 0) VGA_HS <= 0;
    else if(H_cnt > VGA_HS_end) VGA_HS <= 1;
    
    //     VGA_VS
    always@(posedge clk or negedge reset_n)
    if(!reset_n)  VGA_VS <= 1;
    else if(V_cnt == 0) VGA_VS <= 0;
    else if(V_cnt > VGA_VS_end) VGA_VS <= 1;  
        
    
 

   //     data_req
    always@(posedge clk or negedge reset_n)
    if(!reset_n)    data_req <= 0 ;
    else data_req <= ((H_cnt >= Hdat_begin)&&(H_cnt < Hdat_end)&&(V_cnt >= Vdat_begin)&&(V_cnt <= Vdat_end)) ? 1 : 0;
    
     //     VGA_BLK
    always@(posedge clk or negedge reset_n)
    if(!reset_n)    VGA_BLK <= 0 ;
    else VGA_BLK <= data_req ;
            
//    assign VGA_RGB = VGA_BLK? Data:0;
      //     VGA_RGB
    always@(posedge clk )
    if(data_req) 
       VGA_RGB <= data;
    else
        VGA_RGB <= 0;
        
   //address
    always@(posedge clk )
    if(data_req)
     begin
        H_addr <= H_cnt - Hdat_begin;
        V_addr <= V_cnt - Vdat_begin;
     end
     else
       begin
        H_addr <= 0;
        V_addr <= 0;
     end 
endmodule

3. VGA_CTRL_test.v

显示彩条：

TFT_BL表示背光，拉高即可

module VGA_CTRL_test(
  
    input clk , //50MHZ时钟
    input reset_n ,
    output VGA_CLK,
    output VGA_HS, //TFT行同步信号
    output VGA_VS, //TFT场同步信号
    output VGA_BLK,        //VGA 场消隐信号
    output [23:0] VGA_RGB ,//TFT数据输出
    output TFT_BL  //背光
);


    assign TFT_BL = 1;
        
    reg [23:0]disp_data;
    wire [11:0]hcount;
    wire [11:0]vcount;
    wire Clk25M; 
	wire Data_Req;
	
	
	assign VGA_CLK= Clk25M;
	
//	vga_pll vga_pll(
//        .clk_out1(Clk25M),
//        .clk_in1(Clk)
//    );      
clk_vga vga_clk(
        .clk_out1(Clk25M),
        .clk_in1(clk)
    );      
    VGA_CTRL VGA_CTRL(
        .clk(Clk25M),    //系统输入时钟25MHZ
        .reset_n(reset_n),
        .data(disp_data),    //待显示数据
		.data_req(Data_Req),
        .H_addr(hcount),        //VGA行扫描计数器
        .V_addr(vcount),        //VGA场扫描计数器
        .VGA_HS(VGA_HS),        //VGA行同步信号
        .VGA_VS(VGA_VS),        //VGA场同步信号
        .VGA_BLK(VGA_BLK) ,     //VGA 场消隐信号
        .VGA_RGB(VGA_RGB)  //VGA数据输出
    );
         
//定义颜色编码
localparam 
    BLACK       = 24'h000000, //黑色
    BLUE        = 24'h0000FF, //蓝色
    RED     = 24'hFF0000, //红色
    PURPPLE = 24'hFF00FF, //紫色
    GREEN       = 24'h00FF00, //绿色
    CYAN        = 24'h00FFFF, //青色
    YELLOW  = 24'hFFFF00, //黄色
    WHITE       = 24'hFFFFFF; //白色
    
//定义每个像素块的默认显示颜色值
localparam 
    R0_C0 = BLACK,  //第0行0列像素块
    R0_C1 = BLUE,   //第0行1列像素块
    R1_C0 = RED,    //第1行0列像素块
    R1_C1 = PURPPLE,//第1行1列像素块
    R2_C0 = GREEN,  //第2行0列像素块
    R2_C1 = CYAN,   //第2行1列像素块
    R3_C0 = YELLOW, //第3行0列像素块
    R3_C1 = WHITE;  //第3行1列像素块

    wire R0_act = vcount >= 0 && vcount < 120;  //正在扫描第0行
    wire R1_act = vcount >= 120 && vcount < 240;//正在扫描第1行
    wire R2_act = vcount >= 240 && vcount < 360;//正在扫描第2行
    wire R3_act = vcount >= 360 && vcount < 480;//正在扫描第3行
    
    wire C0_act = hcount >= 0 && hcount < 400; //正在扫描第0列
    wire C1_act = hcount >= 400 && hcount < 800;//正在扫描第1列 
    
    wire R0_C0_act=R0_act & C0_act;//第0行0列像素块处于被扫描中标志信号
    wire R0_C1_act=R0_act & C1_act;//第0行1列像素块处于被扫描中标志信号
    wire R1_C0_act=R1_act & C0_act;//第1行0列像素块处于被扫描中标志信号
    wire R1_C1_act=R1_act & C1_act;//第1行1列像素块处于被扫描中标志信号
    wire R2_C0_act=R2_act & C0_act;//第2行0列像素块处于被扫描中标志信号
    wire R2_C1_act=R2_act & C1_act;//第2行1列像素块处于被扫描中标志信号
    wire R3_C0_act=R3_act & C0_act;//第3行0列像素块处于被扫描中标志信号
    wire R3_C1_act=R3_act & C1_act;//第3行1列像素块处于被扫描中标志信号
    
    always@(*)
        case({R3_C1_act,R3_C0_act,R2_C1_act,R2_C0_act,
                R1_C1_act,R1_C0_act,R0_C1_act,R0_C0_act})
            8'b0000_0001:disp_data = R0_C0;
            8'b0000_0010:disp_data = R0_C1;
            8'b0000_0100:disp_data = R1_C0;
            8'b0000_1000:disp_data = R1_C1;
            8'b0001_0000:disp_data = R2_C0;
            8'b0010_0000:disp_data = R2_C1;
            8'b0100_0000:disp_data = R3_C0;
            8'b1000_0000:disp_data = R3_C1;
            default:disp_data = R0_C0;
        endcase
        
endmodule

4. VGA_CTRL_test.xdc

由于使用的是RGB565格式

设置中data 与 VGA_RGB 都为24位

此时在I/O中有几位是无需链接的，会出现[DRC NSTD-1]

【Vivado常见问题】【DRC NSTD-1 DRC UCIO-1】无法生成bitstream（部分管脚位置或电平未指定） - Vivado软件使用和设置 - 芯路恒电子技术论坛 - Powered by Discuz! (corecourse.cn)

xdc文件添加：

set_property SEVERITY {Warning} [get_drc_checks NSTD-1]
set_property SEVERITY {Warning} [get_drc_checks RTSTAT-1]
set_property SEVERITY {Warning} [get_drc_checks UCIO-1]

set_property SEVERITY {Warning} [get_drc_checks NSTD-1]
set_property SEVERITY {Warning} [get_drc_checks RTSTAT-1]
set_property SEVERITY {Warning} [get_drc_checks UCIO-1]

set_property IOSTANDARD LVCMOS33 [get_ports {VGA_RGB[23]}]
set_property IOSTANDARD LVCMOS33 [get_ports {VGA_RGB[22]}]
set_property IOSTANDARD LVCMOS33 [get_ports {VGA_RGB[21]}]
set_property IOSTANDARD LVCMOS33 [get_ports {VGA_RGB[20]}]
set_property IOSTANDARD LVCMOS33 [get_ports {VGA_RGB[19]}]
set_property IOSTANDARD LVCMOS33 [get_ports {VGA_RGB[18]}]
set_property IOSTANDARD LVCMOS33 [get_ports {VGA_RGB[17]}]
set_property IOSTANDARD LVCMOS33 [get_ports {VGA_RGB[16]}]
set_property IOSTANDARD LVCMOS33 [get_ports {VGA_RGB[15]}]
set_property IOSTANDARD LVCMOS33 [get_ports {VGA_RGB[14]}]
set_property IOSTANDARD LVCMOS33 [get_ports {VGA_RGB[13]}]
set_property IOSTANDARD LVCMOS33 [get_ports {VGA_RGB[12]}]
set_property IOSTANDARD LVCMOS33 [get_ports {VGA_RGB[11]}]
set_property IOSTANDARD LVCMOS33 [get_ports {VGA_RGB[10]}]
set_property IOSTANDARD LVCMOS33 [get_ports {VGA_RGB[9]}]
set_property IOSTANDARD LVCMOS33 [get_ports {VGA_RGB[8]}]
set_property IOSTANDARD LVCMOS33 [get_ports {VGA_RGB[7]}]
set_property IOSTANDARD LVCMOS33 [get_ports {VGA_RGB[6]}]
set_property IOSTANDARD LVCMOS33 [get_ports {VGA_RGB[5]}]
set_property IOSTANDARD LVCMOS33 [get_ports {VGA_RGB[4]}]
set_property IOSTANDARD LVCMOS33 [get_ports {VGA_RGB[3]}]
set_property IOSTANDARD LVCMOS33 [get_ports {VGA_RGB[2]}]
set_property IOSTANDARD LVCMOS33 [get_ports {VGA_RGB[1]}]
set_property IOSTANDARD LVCMOS33 [get_ports {VGA_RGB[0]}]
set_property IOSTANDARD LVCMOS33 [get_ports clk]
set_property IOSTANDARD LVCMOS33 [get_ports reset_n]
set_property IOSTANDARD LVCMOS33 [get_ports VGA_BLK]
set_property IOSTANDARD LVCMOS33 [get_ports TFT_BL]
set_property IOSTANDARD LVCMOS33 [get_ports VGA_CLK]
set_property IOSTANDARD LVCMOS33 [get_ports VGA_HS]
set_property IOSTANDARD LVCMOS33 [get_ports VGA_VS]
set_property PACKAGE_PIN W20 [get_ports {VGA_RGB[23]}]
set_property PACKAGE_PIN W19 [get_ports {VGA_RGB[22]}]
set_property PACKAGE_PIN V17 [get_ports {VGA_RGB[21]}]
set_property PACKAGE_PIN V16 [get_ports {VGA_RGB[20]}]
set_property PACKAGE_PIN T15 [get_ports {VGA_RGB[19]}]
set_property PACKAGE_PIN V20 [get_ports {VGA_RGB[15]}]
set_property PACKAGE_PIN U17 [get_ports {VGA_RGB[14]}]
set_property PACKAGE_PIN V18 [get_ports {VGA_RGB[13]}]
set_property PACKAGE_PIN T16 [get_ports {VGA_RGB[12]}]
set_property PACKAGE_PIN R16 [get_ports {VGA_RGB[11]}]
set_property PACKAGE_PIN U19 [get_ports {VGA_RGB[10]}]
set_property PACKAGE_PIN Y19 [get_ports {VGA_RGB[7]}]
set_property PACKAGE_PIN Y18 [get_ports {VGA_RGB[5]}]
set_property PACKAGE_PIN W16 [get_ports {VGA_RGB[4]}]
set_property PACKAGE_PIN Y17 [get_ports {VGA_RGB[3]}]
set_property PACKAGE_PIN W14 [get_ports VGA_VS]
set_property PACKAGE_PIN U14 [get_ports VGA_HS]
set_property PACKAGE_PIN U15 [get_ports VGA_CLK]
set_property PACKAGE_PIN R17 [get_ports TFT_BL ]
set_property PACKAGE_PIN U18 [get_ports clk]
set_property PACKAGE_PIN H18 [get_ports reset_n]


set_property PACKAGE_PIN W15 [get_ports VGA_BLK]