We are using a design with an nrf52832 and USB-C power only socket. We are planning to overload the USBC CC connectors so that we can program via via USB for factory production. In order to enable USBC PD charging (i.e. using s USBC power source and USBC-USBC cable) we need to have 5K1 pull down resistors on both CC lines. The circuit looks like this:
Using a DK, I am unable to program the board, presumably as the SWDIO expects to be pulled up and is more strongly being pulled down than the internal pull up can overcome.
I've tried using an external resistor pulled up against 5V to give a SWDIO voltage of 3V. However, it still won't program, perhaps as the pull up from what is in effect a voltage divider is too strong?
My question is - should this approach work? Would reducing the pull up voltage to something lower than 3V (so easier for the DK to overcome while programming) work perhaps? Or some other approach?
Many thanks.
