PROBLEM: reconnecting a Nucleo-F767ZI with the cut ST-Link.

[loncsemi]

I'm a STM32 beginner and i'm trying to reconnect a Nucleo-F767ZI with the cut ST-Link. I'm working with ChibiOs and i get the error: target voltage may be too low for reliable debugging. But i get some kind of communication (LD1 shows red and green)

I'm using the SWD Port on the ST-Link and an external 5V powersupply (E5V) and I connected the SRT-Link like this: SWCLK to CN11 pin 15, SWDIO to CN11 pin 13, NRST to CN11 pin 14, VDD_Target to CN11 pin 5. I also detached the Jumpers CN4 on the ST-Link and got the Jumper JP3 to E5V.

[Mike_ST]

Hello,

For some reason, the ST-Link report that it cannot sense properly the target voltage through VDD_Target pin.

Check voltage CN11 pin 5, and make sure the connection is OK.

The ST-link firmware is a bit old please update it, some times it fixes problems:

https://www.st.com/en/development-tools/stsw-link007.html

I think you are not so far from make it working.

[loncsemi]

Thanks for the fast reply. I Checked the voltage on CN11 pin 5, it is 3.3V and all connetctions seem to be fine. Also the ST-Link firmwareupdate did't change anything. I'm still getting this Message:

[Mike_ST]

By the way, I don't know your setup, but the error message is talking about JTAG, when you're trying to use SWD.

Other thing is ST-LINK V2 2000KHz is not a frequency that I know.

I know 4000KHz, 1800KHz

Can you post a picture of the setup especially of the ST-Link probe ?

[loncsemi]

I'm not able to post a picture today. I'll try to do that tomorrow. But I tried to check the connection with the STM32 ST-Link Utility Program and this is what i got:

 

Is it possible that my setup is correct, but there's something wrong with my ChibiOs files?

[Mike_ST]

Ok, so your hardware setup seems to be fine.

By the way, please use STM32CubeProgrammer instead of ST-Link Utility,.

STM32CubeProgrammer displays Target voltage after connection.

[Mike_ST]

>> Is it possible that my setup is correct, but there's something wrong with my ChibiOs files?

Yes If the OpenOCD config is wrong, it won't work.

[loncsemi]

I get these with the CubeProgrammer:

The Voltage is still too low tho....

Maybe there are some soldered bridges i might need to detach?

[Mike_ST]

Ok, I found a nucleo F767 somewhere, and I see that R1 is set as N/A on the schematic.

Please fit R1 with 100 Ohms if you can.

[loncsemi]

Sorry for the late reply.

I fitted R1 with 100 Ohms now an this is what i get now:

 

But 6V seems a litte high for me, or am i wrong?