Is SWO necessary to debug the nrf52832 if SWDIO and SWDCLK are connected?

[seanbites]

Hello,

We are currently designing the hardware for a production run of our product using the nrf52832 chip and would still like to have debugging capabilities with breakpoints. Are the SWDIO and SWDCLK lines sufficient (along with gnd and vdd) to debug with breakpoints or do we also need to connect the SWO line? We will be using the SEGGER Flasher Arm device to program/debug the product.

What are the limitations of excluding the SWO line from our design? Also what are the limitations of excluding the TRACEDATA lines?

Thank you very much for your time and if you need any more information, I will gladly supply it.

[RK]

SWDIO and SWDCLK along with VCC and GND are all you need for debugging, SWO is entirely optional and TRACEDATA even more entirely optional. If you're using a standard 10 pin debug header however and have spare GPIOs then you may as well just hook up SWO to the header because it's a free option incase you ever want to use it. Since there's nowhere on that 10 pin header for TRACEDATA, there's nowhere to route that to, only the 20-pin headers support it.

If you're short on GPIOs and need P0.18 for something else, or are designing in a non-standard, even fewer pin hookup for debugging, then you can leave SWO out, you don't need it.

[seanbites]

Thank you very much, this has been very helpful!