Updating the firmware of a X-NUCLEO-BNRG2A1 using the integrated ST-LINK V2-1 of a NUCLEO-L476RG

[paul19]

I'm having trouble updating the firmware of a X-NUCLEO-BNRG2A1 using the procedure described in AN5651 page 4 ("Direct update on the X-NUCLEO-BNRG2A1 expansion board" through the NUCLEO64-L476RG integrated ST-LINK 2-1).

I get this error message in FAIL.TXT: "The interface firmware FAILED to reset/halt the target MCU". And then STM32CubeProgrammer says "Error: No STM32 target found!" when trying to connect.

Maybe this issue relates to SB12, as the Nucleo-64 doc says: "SB12 NRST (target STM32 RESET) must be OFF if CN4 pin 5 is used in the external application".

So should I unsolder SB12? I prefer to ask, because AN5651 doesn't mention it.

Also, if I unsolder SB12, will I have to re-solder it for using the NUCLEO64-L476RG in the standalone way I'm used to?

[paul19]

Anyone on this?

[Mike_ST]

Hello,

yes, better to remove it an replace after you completed the update.

[paul19]

Thanks, @Mike_ST​ . For now I've given up on unsoldering SB12. I purchased a ST-LINK V2 clone instead. I have to say this whole situation is confusing: why do you say it's "better" to unsolder SB12? Is it required or not? Why doesn't AN5651 mention the SB12 issue? And why, if SB12 must be unsoldered and soldered back, isn't there a jumper for this? I will let it go now, and try with my new ST-LINK V2.