STM32L072 does not run the code when activating Reaout protection

[Carlos Bula]

Posted on July 13, 2017 at 16:59

Dear members of ST community,

I have a firmware that is runs perfectly on a L072Z -LRWAN1 discovery board, but the program stops working when activating RDP level 1. I tried removing the stlink jumpers and load the hex using the embeded mcu bootlader, no luck. I tried loading the fw using st-link, the program runs ok, but when activating RDP level 1 using st-link utility,  the program stops working. What could be the problem here?...

Thanks in advance...

[Tesla DeLorean]

Posted on July 13, 2017 at 17:14

Have the firmware output telemetry via the serial port so you understand what's happening internally. Have a Hard Fault Handler that works. Have code in there that writes the option bytes to the desired setting.

[STOne-32]

Posted on July 16, 2017 at 17:12

Dear Carlos,

If you activated RDP Level 1 via ST-link that means your debug is still connected via SWD and so the CPU will halt as it may be seen as an Intrusion.   You need to completely disconnect all St-link signals going to the MCU ( Murata module) and do a complete power cycle of the board to see the program running.  Again , all ST-link signals should be physically disconnected after the power on.

Cheers,

STOne-32.