How to perform reset on nRF51822 chip?

[Andrew]

We have made a custom board using nRF51822 connected to a MPU6050 accelerometer running on a battery.

Currently, we have issues performing reset on the chip. We have to reload the firmware to reset it. Is there a way to reset the device through unplugging the board from the battery then plugging it back on?

[Vidar Berg]

It sounds strange. Is it possible that the board was still powered via the debug connection when you tried power-cycling the board? Also, do you see the same behavior with the SDK examples on your board?

[Andrew]

Hi Vidar. Actually this is a strange issue. I currently use a nRF51822 evaluation board with a MPU6050 module. My firmware uses the MPU6050's zero-G interrupt to detect falls. After flashing the board, everything works fine. Then after removing the power and connecting it back on, the fall detection doesn't work. It is only through re-flashing the board or pressing the reset button will the firmware works properly again.

Is it possible doing a power cycling doesn't completely reset the chip?

For our production boards, we might not have space for a button. So we have to do power on then off to do the resetting.