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nRF51822 - After power up, program does not start without cycling the reset pin.

Hello, we have been using a nRF51822 8-pin RF module for a while now for various products, the pinout is as follows: power, P0.00, P0.01, P0.09, P0.11, SWDIO, SWDCLK, ground.

I am using SDK13 in Keil, using a J-link SWD device for programming, and using SEGGER RTT library and RTT Viewer for writing to prompt.

The program does not start without me shorting SWDIO to ground first. This is the case if I have the J-link connected, if I just now flash the program with Keil, or if I have no J-link connected to it and I just power the device up all on its own. I always have to short SWDIO to ground before it will start.

Can you give me any help/advice on what might be the problem here? Thanks and any help is greatly appreciated!

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