DS90UB949A-Q1可以通过I2C读写HDMI External Local EDID (EEPROM),需要什么前提条件,以及用什么寄存器可以更改此EDID?谢谢
您好,
已经收到了您的案例,调查需要些时间,感谢您的耐心等待。
请参阅有关EDID编程的文档。
Please refer to below files
4401.Using EDID in FPD-Link Devices (1).pdf
是否要通过 I2C 写入覆盖外部 EEPROM EDID? 您可以使用附加的脚本来执行此操作。
# Script to load EDID serAddr =0x18 exEDID = [0x00,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0x00,0x04,0x21,0x00,0x00,0x00,0x00,0x00,0x00, 0x01,0x00,0x01,0x03,0x80,0x26,0x15,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x01,0x00,0x01,0x00,0x01,0x00,0x01,0x00, 0x01,0x00,0x01,0x00,0x01,0x00,0x84,0x3A,0x80,0xB4,0x70,0x38,0x32,0x40,0x50,0x28, 0x85,0x00,0x00,0x00,0x00,0x00,0x00,0x18,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x10,0x00,0x00, 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x10, 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0xC8, 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00] board.WriteI2C(serAddr,0x48,0xD) for x in range(0,256): board.WriteI2C(serAddr,0x49,x) board.WriteI2C(serAddr,0x4B,exEDID[x])
对于本地EDID (EEPROM)-这不能通过正常949 I2C完成。
对于外部本地EDID,必须设置EDID_SEL = 1,然后REM_EDID_LOAD无关紧要。 它可以是0或1,因为SRAM访问在949 DDC接口中被禁用。
EDID的通信将直接发生在HDMI源和DDC总线上的EEPROM之间。 949根本不参与该配置的EDID事务。 您必须将EEPROM放置在EVM上的DDC总线插座上,并且必须已将EDID刷新到EEPROM中。 此外,EEPROM设备必须具有8位I2C地址0xA0,以便HDMI源可以识别它。
另请注意,要启动HDMI交换,HPD必须高于949。 要使HPD较高,949必须检测到下游DES连接,因此您需要使用正确的链接将949 EVM连接到DES EVM。