I have a nRF5340 development board, and I want to switch to high voltage mode. ( in order to generate 3.3v voltage on GPIO as the result.)
This is my steps:
1. switch the dev board to Li-Po.
2. use "TRACE" and J-Link to connect the board to PC (via SWCLK and SWDIO).
3. erase the board,
4. run the command: nrfjprog -f nrf53 --memwr 0x00FF8010 --val 0xFFFFFFFD
to write the register.
5. flash my program into the board.
I hope the forth step could change the board into high voltage mode, and I could get the 3.3v from GPIO. But after I test, I still get 1.8v from GPIO.
Is there something wrong? How can I solve this problem and get 3.3v GPIO output？