On this page, we will go through the status window of the PDC page.

Initial Role

Here you can selelct the role that the UCD test device has. Click here to read more about the USB-C roles.

When DRP role is selected it is possible that the contract negotiation will get “jammed”. Then we would be given the DFP role even if we have selected UCD-340 as a sink device. Our TE does not have a preference to be sink or source. This will change with UCD-500 going forward. If we select DRP and are assigned a DFP role, we have to send a data role swap request.

CC Pull-up

Before the PD contrcat is done, the CC pullup provides power for the USB-C connectors.

Reject Swaps

Show from event log. For example, if a device has been assigned to a role that is not it’s preference it can send a swap request. E.g. if a smartphone is assigned as a power source, it can send a PR swap request as it wants to be the power sink

UCD-340 Status

This window shows general information about the UCD test device such as the PD spec and the vendor ID.


From USB-C to 3,5mm jack adaptor would be a DUT. At the moment we can’t output audio. As of now we can only simulate audio accessory.

USB-C also enables analog audio. The USB standard supports “Audio Accessory Mode”, whereby the D+/D- pins switch roles to support analog audio signals.

USB-C spec supports a “Debug-Accessory Mode” specification, where some pins are allowed to be repurposed if pins CC1 and CC2 are pulled up to Logic-1. Under these circumstances, the pin functions are released, and a JTAG programmer can step in to borrow them.

  • For whom? DUT?

USB Bypass function

In UCD-340 you have both Type C and Type A connectors.  When you wanna test USB enumeration because in UCD-340 we don’t have USB data.