Correct wiring for programming external module with nRF51-DK (and Keil)

RE: Correct wiring for programming external module with nRF51-DK (and Keil)

Gordon — Wed, 18 May 2016 13:32:28 GMT

Just to add - I have had no luck with P20 at all when programming nRF52. P19 works great though.

RE: Correct wiring for programming external module with nRF51-DK (and Keil)

muhkuhns — Wed, 29 Apr 2015 19:53:13 GMT

Thanks for pointing this out! Now I just need to get the software part for it running :D

RE: Correct wiring for programming external module with nRF51-DK (and Keil)

MartinBL — Wed, 29 Apr 2015 07:27:34 GMT

EDIT: Sorry, I was mistaken. You can use P20 as well. It is an additional connector meant for shields with a different pinout standard. I updated my answer above.

RE: Correct wiring for programming external module with nRF51-DK (and Keil)

muhkuhns — Wed, 29 Apr 2015 07:22:30 GMT

Thanks for your confirmation on the other two matters but are you sure about the P19/20? This is taken from the nRF51-DK User Guide. Because I have no matching connector for P19 the pin slots of P20 would be easier to use

RE: Correct wiring for programming external module with nRF51-DK (and Keil)

MartinBL — Wed, 29 Apr 2015 07:16:18 GMT

Hi! You can use P19 or P20. The Vtg (aka Vref) is only used to detect a voltage on the target board. This is how your nRF51 DK knows an external board is present. From the J-Link manual:

This is the target reference voltage. It is used to check if the target has power, to create the logic-level reference for the input comparators and to control the output logic levels to the target. It is normally fed from Vdd of the target board and must not have a series resistor.

It is perfectly fine to use the VDD pins on the nRF51 DK to provide power to your target (assuming the target needs 3 volts).