About the Buttonless DFU of NRF51822 QFAA, SDK12.3.0.

[cgha]

app and dfu works after I program the merged hex from bootloader_setting, bootloader, softdevice, app using Program application tab, but if I erase chip, reprogram it with "Lock entire chip from readback" enabled, my app seems can not work. Why? I use NRF51822 and SDK12.3.0, external 32K crystal.

[Vidar Berg]

Hello,

This should not be a problem as long as you are not enabling code region protection (UICR.CLENR0). Can you post a screenshot showing which setting your are enabling in your programmer app?

Best regards,

Vidar

[cgha]

I just use nrfgo 1.21.2.10 for programming

[Vidar Berg]

Please try to enable readback protection with nrfjprog instead (nRF Command line tools), and see if you observe the same problem. nRFGo studio was deprecated several years ago and may not be compatible with newer versions of the Jlink drivers.

nrfjprog --program HEX_FILE --chiperase --verify --reset
# Enable readback protection
nrfjprog --rbp all

[cgha]

It's OK to use nrfjprog. But Sometimes the nrfjprog --rbp all command can not execute successfully. It complain "can not connect any NRF device". May be my board has an external HW watchdog chip named tps3823 lead to this issue. Thanks!

[Vidar Berg]

Yes, this operation will fail if the chip is reset by the WD during the write.