1. 概述
HDMI英文名为High Definition Multimedia Interface,是一种数字化视频、音频接口。 现已
广泛应用于高清数字电视、PC显示器等产品中。
这里我们使用Silicon Image公司的SiI9134作为HDMI发送芯片,支持HDMI 1.3标准。
2. 设计框图
视频源由FPGA内部产生,sii9134的配置通过I2C模块完成。这里以720P60为例完成设计。
3. Sii9134配置
这里将Sii9134配置成YCbCr422输入,RGB444输出模式。
void sii9134_init() { sccb_senddata(0x72,0x05,0x01); //reset all sections sccb_senddata(0x72,0x05,0x00); //disable reset sccb_senddata(0x72,0x08,0x37); //VSYNC and HSYNC, 24bit, rising edge, normal operation sccb_senddata(0x72,0x0c,0x00); sccb_senddata(0x72,0x0d,0x01); sccb_senddata(0x72,0x4B,0x00); //Blue sccb_senddata(0x72,0x4C,0x00); //Green sccb_senddata(0x72,0x4D,0xff); //Red sccb_senddata(0x72,0x82,0x25); //FPLL*IDCK, enable internal source termination sccb_senddata(0x72,0x83,0x19); //HDMI PLL/2, PLL filter feedback/4, PLL filter front/2 sccb_senddata(0x72,0x84,0x31); //50uA, PLL filter post/2 sccb_senddata(0x72,0x85,0x01); //HDMI transmitter PLL front/2 sccb_senddata(0x72,0x32,0x04); //h-blank sccb_senddata(0x72,0x33,0x41); //enable DE, positive polarity, left-blank(370 pixels) sccb_senddata(0x72,0x34,0x19); //v-blank(30 lines) sccb_senddata(0x72,0x36,0x00); //the width of active display sccb_senddata(0x72,0x37,0x05); //the width of active display(1280) sccb_senddata(0x72,0x38,0xD0); //the height of active display sccb_senddata(0x72,0x39,0x02); //the height of active display(720) sccb_senddata(0x72,0x3E,0x00); sccb_senddata(0x72,0x40,0x6e); sccb_senddata(0x72,0x41,0x00); sccb_senddata(0x72,0x44,0x29); sccb_senddata(0x72,0x45,0x00); sccb_senddata(0x72,0x46,0x05); sccb_senddata(0x72,0x47,0x06); sccb_senddata(0x72,0x48,0x30); sccb_senddata(0x72,0x49,0x00); sccb_senddata(0x72,0x4a,0x3c); //////////////////////////////////////////////// sccb_senddata(0x7a,0x01,0x02); sccb_senddata(0x7a,0x02,0x01); sccb_senddata(0x7a,0x03,0x00); sccb_senddata(0x7a,0x04,0x18); sccb_senddata(0x7a,0x05,0x00); sccb_senddata(0x7a,0x14,0x11); sccb_senddata(0x7a,0x1D,0x40); sccb_senddata(0x7a,0x21,0x02); sccb_senddata(0x7a,0x22,0x2B); sccb_senddata(0x7a,0x2F,0x01); sccb_senddata(0x7a,0x40,0x82); sccb_senddata(0x7a,0x41,0x02); sccb_senddata(0x7a,0x42,0x0d); sccb_senddata(0x7a,0x43,0x59); sccb_senddata(0x7a,0x44,0x11); sccb_senddata(0x7a,0x45,0x28); sccb_senddata(0x7a,0x46,0x00); sccb_senddata(0x7a,0x47,0x04); sccb_senddata(0x7a,0x48,0x00); sccb_senddata(0x7a,0x49,0x00); sccb_senddata(0x7a,0x4A,0x00); sccb_senddata(0x7a,0x4B,0xD1); sccb_senddata(0x7a,0x4C,0x02); sccb_senddata(0x7a,0x4D,0x00); sccb_senddata(0x7a,0x4E,0x00); sccb_senddata(0x7a,0x4F,0x01); sccb_senddata(0x7a,0x50,0x05); sccb_senddata(0x7a,0x51,0x00); sccb_senddata(0x7a,0x52,0x00); sccb_senddata(0x7a,0x80,0x84); sccb_senddata(0x7a,0x81,0x01); sccb_senddata(0x7a,0x82,0x0a); sccb_senddata(0x7a,0x83,0x70); sccb_senddata(0x7a,0x84,0x01); sccb_senddata(0x7a,0x85,0x00); sccb_senddata(0x7a,0x86,0x00); sccb_senddata(0x7a,0x87,0x00); sccb_senddata(0x7a,0x88,0x00); sccb_senddata(0x7a,0x89,0x00); sccb_senddata(0x7a,0x8a,0x00); sccb_senddata(0x7a,0x8b,0x00); sccb_senddata(0x7a,0x8c,0x00); sccb_senddata(0x7a,0x8d,0x00); sccb_senddata(0x7a,0x3e,0x33); }
4. FPGA逻辑设计
FPGA逻辑完成视频源生成、HDMI配置、RGB转YCbCr功能。下面表格给出RGB转YC的公式。
Video Format |
Formulas |
576p |
Y = 0.299R′ + 0.587G′ + 0.114B′ Cb = –0.172R′ – 0.339G′ + 0.511B′ + 128 Cr = 0.511R′ – 0.428G′ – 0.083B′ + 128 |
480p |
|
240p |
|
720p |
Y = 0.213R′ + 0.715G′ + 0.072B′ Cb = –0.117R′ – 0.394G′ + 0.511B′ + 128 Cr = 0.511R′ – 0.464G′ – 0.047B′ + 128 |
1080p |
//file name: hdmi_vid_gen.v //author: shugen.yin //date: 2016.9.21 //function: hdmi video generation //log: module hdmi_vid_gen( input clk, //74.25MHz input rst_n, output hdmi_clk, output hdmi_txde, output hdmi_hs, output hdmi_vs, output [15:0] hdmi_data ); parameter IMG_HDISP = 16‘d1280; parameter IMG_VDISP = 16‘d720; parameter H_OFFSET = 0; wire pclk; assign pclk = clk; assign hdmi_clk = pclk; assign hdmi_hs = hsync; assign hdmi_txde = data_valid; assign hdmi_vs = vsync; assign hdmi_data = data; reg [11:0] vcnt; reg [15:0] hcnt; reg vsync; reg hsync; reg data_valid; reg [15:0] data; reg [7:0] red; reg [7:0] green; reg [7:0] blue; always @(posedge pclk) if(hcnt>=(IMG_HDISP+259)) //720p hcnt <= 0; else hcnt <= hcnt + 1‘b1; always @(posedge pclk) if(hcnt>=(IMG_HDISP+259)) if(vcnt>=(IMG_VDISP+24)) vcnt <= 0; else vcnt <= vcnt + 1‘b1; else vcnt <= vcnt; always @(posedge pclk) if((hcnt>=IMG_HDISP+H_OFFSET) & (hcnt<=(IMG_HDISP+H_OFFSET+32)) & (vcnt>=0 | (vcnt<IMG_VDISP))) hsync <= 1‘b1; else hsync <= 1‘b0; always @(posedge pclk) if(vcnt<=(IMG_VDISP+2+6) & vcnt>=(IMG_VDISP+2)) vsync <= 1‘b1; else vsync <= 1‘b0; reg cbcr_reg; always @(posedge pclk) if(vsync) begin data <= 0; cbcr_reg <= 0; red <= 0; green <= 0; blue <= 0; end else if((hcnt>=0) & (hcnt<(IMG_HDISP+0)) & (vcnt>=0) & (vcnt<(0+IMG_VDISP/4))) begin if(~cbcr_reg) begin data[7:0] <= y; data[15:8] <= cb; end else begin data[7:0] <= y; data[15:8] <= cr; end cbcr_reg <= ~cbcr_reg; red <= 8‘hf0; green <= 8‘hf0; blue <= 8‘h00; end else if((hcnt>=0) & (hcnt<(IMG_HDISP+0)) & (vcnt>=(0+IMG_VDISP/4)) & (vcnt<(0+2*IMG_VDISP/4))) begin if(~cbcr_reg) begin data[7:0] <= y; data[15:8] <= cb; end else begin data[7:0] <= y; data[15:8] <= cr; end cbcr_reg <= ~cbcr_reg; red <= 8‘hf0; green <= 8‘h00; blue <= 8‘h00; end else if((hcnt>=0) & (hcnt<(IMG_HDISP+0)) & (vcnt>=(0+2*IMG_VDISP/4)) & (vcnt<(0+3*IMG_VDISP/4))) begin if(~cbcr_reg) begin data[7:0] <= y; data[15:8] <= cb; end else begin data[7:0] <= y; data[15:8] <= cr; end cbcr_reg <= ~cbcr_reg; red <= 8‘h00; green <= 8‘hf0; blue <= 8‘h00; end else if((hcnt>=0) & (hcnt<(IMG_HDISP+0)) & (vcnt>=(0+3*IMG_VDISP/4)) & (vcnt<(0+IMG_VDISP))) begin if(~cbcr_reg) begin data[7:0] <= y; data[15:8] <= cb; end else begin data[7:0] <= y; data[15:8] <= cr; end cbcr_reg <= ~cbcr_reg; red <= 8‘h00; green <= 8‘h00; blue <= 8‘hf0; end else begin data <= 0; cbcr_reg <= 0; red <= 0; green <= 0; blue <= 0; end always @(posedge pclk) if(vsync) data_valid <= 0; else if((hcnt>=0) & (hcnt<(IMG_HDISP+0)) & (vcnt>=0) & (vcnt<(0+IMG_VDISP/4))) data_valid <= 1; else if((hcnt>=0) & (hcnt<(IMG_HDISP+0)) & (vcnt>=(0+IMG_VDISP/4)) & (vcnt<(0+2*IMG_VDISP/4))) data_valid <= 1; else if((hcnt>=0) & (hcnt<(IMG_HDISP+0)) & (vcnt>=(0+2*IMG_VDISP/4)) & (vcnt<(0+3*IMG_VDISP/4))) data_valid <= 1; else if((hcnt>=0) & (hcnt<(IMG_HDISP+0)) & (vcnt>=(0+3*IMG_VDISP/4)) & (vcnt<(0+IMG_VDISP))) data_valid <= 1; else data_valid <= 0; wire [7:0] y; wire [7:0] cb; wire [7:0] cr; rgb2ycbcr rgb2ycbcr_inst ( .clk(pclk) , // input clk_sig .rst_n(rst_n) , // input rst_n_sig .red(red) , // input [7:0] red_sig .green(green) , // input [7:0] green_sig .blue(blue) , // input [7:0] blue_sig .y(y) , // output [7:0] y_sig .cb(cb) , // output [7:0] cb_sig .cr(cr) // output [7:0] cr_sig ); endmodule
5. 最终结果
在显示器上显示1280*[email protected]帧的彩条视频。
时间: 2024-11-14 01:40:48