Hi Devzone. I have a PCA10056 that I'm using to set up for CI / HIL testing, using an external nRF52840 on another PCB. The external SWD on P19 is working perfectly. I am able to flash and debug the external nRF52. I'm trying to connect the external nRF52 UART to RXD/P0.08 and TXD/P0.06 for scripting, without HW flow control. The interface MCU does not seem to be routing the UART traffic to USB CDC I can verify my UART signal on TP2 / IMCU_RxD, so IF_OFF seems to be set correctly. I tried a few things, such as flipping SW6, but that causes my USB CDC to drop out. SW7 does not seem to affect anything either. When I use the on board nRF52840, the virtual COM port does function. So this is strictly a problem when trying to inject the external UART to the virtual COM port.

PCA10056 + external SWD (debug out P19) and external UART to Virtual COM port

ms360 5 hours ago

Hi Devzone.

I have a PCA10056 that I'm using to set up for CI / HIL testing, using an external nRF52840 on another PCB.

The external SWD on P19 is working perfectly.
- I am able to flash and debug the external nRF52.
I'm trying to connect the external nRF52 UART to RXD/P0.08 and TXD/P0.06 for scripting, without HW flow control.
- The interface MCU does not seem to be routing the UART traffic to USB CDC
- I can verify my UART signal on TP2 / IMCU_RxD, so IF_OFF seems to be set correctly.

I tried a few things, such as flipping SW6, but that causes my USB CDC to drop out.
SW7 does not seem to affect anything either.

When I use the on board nRF52840, the virtual COM port does function.
So this is strictly a problem when trying to inject the external UART to the virtual COM port.