VGA Vesa DDC显示接口
VGA 是 Video Graphics Adapter(Array) 的缩写，VESA 是 Video Electronics Standards Association 的缩写，DDC 是 Display Data Channel 的缩写，信号类型为模拟类型，显示卡端的接口为 15 针母插座：
显示器连线端的接口为 15 针公插头： 
| 引脚定义 |
| Pin | Name | Dir | Description |
|---|---|---|---|
| 1 | RED |
| Red Video (75 ohm, 0.7 V p-p) |
| 2 | GREEN |
| Green Video (75 ohm, 0.7 V p-p) |
| 3 | BLUE |
| Blue Video (75 ohm, 0.7 V p-p) |
| 4 | RES | - | Reserved |
| 5 | GND |
| Ground |
| 6 | RGND |
| Red Ground |
| 7 | GGND |
| Green Ground |
| 8 | BGND |
| Blue Ground |
| 9 | +5V |
| +5 VDC |
| 10 | SGND |
| Sync Ground |
| 11 | ID0 |
| Monitor ID Bit 0 (optional) |
| 12 | SDA |
| DDC Serial Data Line |
| 13 | HSYNC or CSYNC |
| Horizontal Sync (or Composite Sync) |
| 14 | VSYNC |
| Vertical Sync |
| 15 | SCL |
| DDC Data Clock Line |
