Bootloader programming issue The flash is not erased

[ting²]

Hi everyone, I am using the nRF51822, I have an issue of programming the bootloader. It is said that the flash is not erased. But I just did an erase all before programming. Is there anyone who encountered the same issue? Thanks!

[bjorn-spockeli]

Yes, P0.21 should behave as an ordinary GPIO pin if the PSELRESET registers are not set.