STM32L151RET6 is in halt state

[Nimit Vachhani]

Greetings,

I have a board with STM32L151RET6. I can program the controller using st-link, but as soon as i try to enter debug mode it ide says cannot read memory. I am using keil and i am trying to enter debug modue using keil debugger and stlink.

I have also connected 10k ohm to boot0 and gnd. Still keil cannot enter debugger. It says error *** error 122: AGDI: memory read failed (0xFFFFFFFE)

Please help me with the error.

Controller can be programmed using st link as well as keil.

[Tesla DeLorean]

Make sure NRST is connected, and select "Connect Under Reset" in options.

​

M​ake sure not to reconfigure to debug pins, or go into low power modes.

[Nimit Vachhani]

NRST is connected to GND using 0.1uF capacitor and "Connect Under Reset" is selected. Are there any chances that controller is blown ?

[Tesla DeLorean]

Is NRST connected to the ST-LINK?​

[Nimit Vachhani]

nopes. I never connect nrst to st link. Let me be clear that this controller was bought from china. I have already made one board with original ic bought from st website and it is working perfectly fine.

[Nimit Vachhani]

Hi,

I have connected 0.1uF capacitor to NRST and other end at ground. Still the problem remains. I tried debugging in stm32 cube ide and getting below error

Break at address "0xfffffffe" with no debug information available, or outside of program code.

fffffffe:  Failed to execute MI command: -data-disassemble -s 4294967294 -e 4294967393 -- 3  Error message from debugger back end: Cannot access memory at ddress 0xfffffffe

Any idea what is going on ?

[Tesla DeLorean]

Can you connect to and inspect the part using STM32 Cube Programmer or the ST-LINK Utilities?​

[Nimit Vachhani]

Greetings Tesla,

Problem found. It was in options byte - nBFB2 was un-checked. I checked it and it started running from internal memory. After lots of reading suddenly my attention was drawn to that bit / flag.

Now controller is running as it should.

Thanks for help.