Hello,
My apologies for the delayed response, I was away during our company wide holiday shutdown. Were you able to resolve or make any progress on the issue during this time?
Thank you for sending me the scope shots. Can you please send me a copy of the schematic as well?
A couple of possible scenarios:
1.) It looks like the DDC_COM bus is disabled on the ADV3002 ?
Both the SDA and SCL lines of the DDC_COM bus are floating to +5V. It does not appear to be responding to the master.
Could you please check the setting for register address 0x04 (Auxiliary Buffer enables)? The default setting for this register should be 0x07. This ensures that the DDC buffer is enabled. If this Bit 1 of this register is set to 0 then the DDC buffer will be disabled.
2.) Is the switch setting correct?
Could you please check the state of the TX_EN, SEL1, and SEL0 pins during both configurations?
When using PORTB, TX_EN and SEL0 should be high, and SEL1 should be low
When using PORTC TX EN and SEL1 should be high, and SEL0 should be low
Alternatively, can you please verify the BIT 2 setting for register address 0x00?
If using SEL[1:0] parallel pins, this bit should be set to 0. If controlling the switch via I2C this bit should be set to 1. The switch will then be configured based on the settings of BIT 1 and BIT 0 of this register.
Regards,
Jarrod