cksiang80
Newbie level 1
edid no display
I have a problem on DVI-D display. There is no display when connect a specify model of a LCD monitor to board.
EDID header format, byte 0~7 contains 00 FF FF FF FF FF FF 00 respectively. On a monitor that has no display, it return 00 FF FF FF FF FF FF FF while on a good monitor with display, it returns 00 FF FF FF FF FF FF 00 on oscilloscope.
When further zoom in, at the last falling edge of SCL (30%), the hold time of SDA line with reference to the SDA (70%) is
1. 2nS on board.
2. -210nS at monitor.
The hold time at board is small and propagation delay through monitor cable causing the the negative hold time at monitor receiving side.
I check the I2C spec, it state that the hold time at device should > 0nS. But i did not see any hold time specified for the driver/source.
Do we have spec for source?
What is the significant of EDID header? Does monitor based on the full header or particular byte to turn on the display on screen?
I have a problem on DVI-D display. There is no display when connect a specify model of a LCD monitor to board.
EDID header format, byte 0~7 contains 00 FF FF FF FF FF FF 00 respectively. On a monitor that has no display, it return 00 FF FF FF FF FF FF FF while on a good monitor with display, it returns 00 FF FF FF FF FF FF 00 on oscilloscope.
When further zoom in, at the last falling edge of SCL (30%), the hold time of SDA line with reference to the SDA (70%) is
1. 2nS on board.
2. -210nS at monitor.
The hold time at board is small and propagation delay through monitor cable causing the the negative hold time at monitor receiving side.
I check the I2C spec, it state that the hold time at device should > 0nS. But i did not see any hold time specified for the driver/source.
Do we have spec for source?
What is the significant of EDID header? Does monitor based on the full header or particular byte to turn on the display on screen?