DS90UB940-Q1EVM: I2C initialization necessary?

Hi Wei,

Assuming PCLK is matched, there is no need for I2C initialization to achieve LOCK between the devices.

What register are you reading to indicate that your 940 EVM has valid PASS and LOCK?

Best,

Nikolas

The Lock pin measures close to 0v. Usb2any doesn’t get the serializer info as well.

We double checked the schematic. Differences from the evm are We missed 10uf, 1 uf and 0.1uf for pin 33, only used 0.01uf; power filter used is 60r at 100Mhz instead of 120r; voltage for mode_sel0 is not accurate. Can any of these render the ic not functioning?

Hi Nikolas, 

Any further insight on the issue? Thank you.

Hi Wei,

In this case since the USB2ANY detect the serializer we should be focusing on the 927. Is the serializer an EVM or a custom board? 

Wei Xiao said:

We double checked the schematic. Differences from the evm are We missed 10uf, 1 uf and 0.1uf for pin 33, only used 0.01uf; power filter used is 60r at 100Mhz instead of 120r; voltage for mode_sel0 is not accurate. Can any of these render the ic not functioning?

Is this for 927 or 940?

Best Regards,

Gil Abarca

It’s for 940. We can NOT get the serializer info. The serializer is in an oem radio. We visually examined and found it’s ub927

Hi Wei,

Since you cannot detect the downstream serializer, this indicates there may be some link or lock instability?

Is video being sent by the source when you are trying to detect the serializer. By default, RX_LOCK is established only when receiving active video (based on register 0x34[6].

If video is not being sent, please set 0x34[6] = 1 and see if LOCK is established.

Best,

Nikolas