nrfjprog write verify failed

[gaminn]

With any nrfjprog (9.8, 9.7, WIndows 10) I get ERROR: Write verify failed.

"C:\Program Files\Nordic Semiconductor\nrf5x\bin\nrfjprog.exe" -f nrf52 --verify s.hex

I'm able to program my device using nRFgo Studio or J-Flash - it programs and verifies the firmware correctly.

I examined it a little and I can see that nrfjprog changes some bytes, mainly at offset 0x7C - 0x7F of the hex, where it programs FF FF FF FF instead of what is in the hex.

For NRF51 family nrfjprog works.

Tried different versions of nrfjprog and J-Link and also different devices to program.

[gaminn]

You are right, it is about the speed. I can use max -c 1000 with nrfjprog. When I set -c 1001 and higher it stops working. It is weird as I can set even 8 MHz in J-Flash utility and it programs and verifies it.

My cablee is 20 cm long dupont cable.

Any idea why is nrfjprog sensitive to speed setting and other programming utilities (J-Flash) not?

[Øyvind]

The valid clockspeed for nrfjprog is between 125 kHz and 50000 kHz. What programming tool are you using? 

Segger J-Flash is a more developed tool and may have more safety features when it comes to writing flash compared to nrfjprog.

[gaminn]

I use Segger J-link.

To summarize it: nRFgo studio works (don't know what speed it sets), J-Flash works (8 MHz, didn't test more) and nrfjprog works only for nrf51 (-f nrf51; didn't test with speed explicitly set).

nrfjprog with -f nrf52 fails with speed > 1000.

I will try it on different PC also...

[gaminn]

I want to enable readback protection for nrf52 but I get the same error:

"C:\Program Files (x86)\Nordic Semiconductor\nrf5x\bin\nrfjprog.exe" -f nrf52 -c 1000 --rbp ALL
ERROR: There is no debugger connected to the PC with the given serial number.

Can you please advise what could be wrong in this case?

[Øyvind]

Does is it not work with nrfjprog --ids? Ref. case 228271

-Øyvind