10 years, 1 month ago.

Access to SWD interface on the nRF51822-mKIT

I want use the mbed library in uVision 4 IDE and download/debug using the SWD. I have looked at the schematics of the board and can't figure out a good way to access to SWDIO and SWDCLK (Pins 23 and 24) on the nrF51822 chip. How can we access the pins to have SWD interface?

Question relating to:

The nRF51822-mKIT is a low cost ARM mbed enabled development board for Bluetooth® Smart designs with the nRF51822 SoC. The kit gives access to all GPIO pins via pin headers …

I used one of these chips for a job last year. Uploading code using the J-Link debugger was not a problem over SWD, If I remember correctly we had to cut some of the lines on the EVAL board to get it to work properly, but it was outlined in the user manual. Mind you we were not using the mbed api (but that will make no difference when uploading code)

posted by Luke Gary 06 Jun 2014

2 Answers

10 years, 1 month ago.


You should be able to access these lines by soldering to the exposed vias on the top layer. Take a look at the schematics and the PCB prints to see which vias I mean.

Accepted Answer
10 years, 1 month ago.

Just going out on a limb here, because I don't actually own one of these, but doesn't the on-board CMSIS-DAP interface do exactly this when used with Keil?

Thanks for the reply Neil, but I intend on removing the CMSIS-DAP interface from my custom board that I am working on. I wanted to validate my assumption by trying this out on the nRF51822-mKIT board. My design intent is to use a j-link and Keil MDK to program and debug. The nrF51822 chip has an internal pull-up and pull-down resistors for the SWD interface so theoretically all I need is access to the pins and a j-link.

What you have proposed is true, and I will try that first, but it doesn't help me validate if my design assumption for eliminating CMSIS-DAP is correct.

posted by Saif Sabti 02 Jun 2014