Other Parts Discussed in Thread: DS90UH949-Q1EVM
Hello members,
I am using a 1024x8 bits EEPROM (AT24C08A) with the DS90UB949-Q1EVM kit. The external EEPROM is placed on the position of "U3" in the evaluation kit. I have DELL laptop device connected to the Serializer EVK kit using the HDMI cable, and on the other hand the Serializer is connected to a display device using the LVDS cable.
I have programmed the AT24C08A EEPROM using an external MCU device, and written the E-EDID bytes of 512 bytes in the EEPROM device. I can share the E-EDID data bytes if you need just in case.
I have connected a I2C sniffer device to see the communication happening on the DDC I2C bus. I have connected the I2C sniffer device on the SCL, SDA lines of the "J24" header.
All the jumpers are connected with the default setting as mentioned in the "DS90UH949-Q1EVM User's Guide" while the "MODE_SEL0" DIP switch is set to #5 and "MODE_SEL1" DIP switch is set to #1.
Now, when I am powering up the EVK kit, I can see on the I2C sniffer device that the I2C master (possibly Serializer device) is querying for the "0x50" (7-bit address) device on the I2C bus for the E-EDID data bytes, and the connected "AT24C08A" EEPROM device is sending the contents of EEPROM data on the serializer bus. I can see the data bytes are same the E-EDID data bytes that I have programmed in the EEPROM device.
As per I2C sniffer device, Master requests the data from 0x50 address I2C slave device at memory address of 0x00, then the EEPROM is sending the data bytes present the queried memory address. After transferring the 0x7F data bytes, "STOP" is generated by the Serializer device (I2C master), and again requesting the data from the 0x50 address I2C slave from the memory address of 0x80 and then again EEPROM is sending the data contents present at 0x80 memory address, and sending again next 128 data bytes, before "STOP" generated by the Serializer device (I2C master).
After that, the Serializer device ((I2C master) is again requesting the 0x50 address I2C slave device at memory address of 0x00, and again the steps are continued as above paragraph.
On the connected DELL laptop, I can just receive the 256 bytes of E-EDID data bytes sent by the Serializer device, but if I have programmed the 512 bytes of external EEPROM then why the Serializer device is only requesting till 8-bit memory address, it is only reading the 256 data bytes of E-EDID from the EEPROM.
I need to solve this issue, as I want to send the 512 bytes of E-EDID information from the Serializer device to the DELL laptop (or can be any other device). Is there any setting using which I can configure the Serializer device to request for 512 bytes of E-EDID information from the external EEPROM connected on the board.
Please help me to sort this issue. Please reply asap.
Thanks & Regards,
Vivek Karna
