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：
Pin
Name
DescripTIon
Pin
Name
DescripTIon
1
RED
Red Video (75 ohm, 0.7 V p-p)
9
+5V
+5 VDC
2
GREEN
Green Video (75 ohm, 0.7 V p-p)
10
SGND
Sync Ground
3
BLUE
Blue Video (75 ohm, 0.7 V p-p)
11
ID0
Monitor ID Bit 0
4
RES
Reserved
12
SDA
DDC Serial Data Line
5
GND
Ground
13
HSYNC or CSYNC
Horizontal Sync (or Composite Sync)
6
RGND
Red Ground
14
VSYNC
VerTIcal Sync
7
GGND
Green Ground
15
SCL
DDC Data Clock Line
8
BGND
Blue Ground
