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STM32F303 debug

Associate II


I am working on a project (a custom borad with STM32F303) is it possible to debug it using my nucleo board 32H745 ?

The only pinout I did for the MCU is SWD interface with (SWO, SWDIO and SWCLK). I tried connecting pins on the nucleo board in connector CN2 to my MCU but in STM32CubeIDE shows this : 

Target no device found

Error in initializing ST-LINK device.
Reason: No device found on target.



Yes. You need to connect GND/SWDIO/SWCLK between the board and remove/disconnect the two jumpers for SWDIO/SWCLK on the nucleo boad. The user manual goes over how to do this, but they should be fairly obvious to spot, right on the stlink portion. Unclear if SWO will be available. Perhaps it will be if you hold the STM32H7 chip in reset, or don't initialize it on that chip.

Your target board also needs to be powered. Voltage should show up in STM32CubeProgrammer.

Also possible your custom board has hardware errors that are preventing the connection.

Wrong, mostly.

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The jumpers you mentionned on Nucleo32H745 are the SB16 and SB17 ? 

> Nucleo32H745 

The only nucleo board with an H745 is a nucleo-144 board. I am assuming you mean NUCLEO-H745ZI-Q.

> SB16 and SB17

Hmm, on other boards they are jumpers on male header pins. On this board, I'm not actually sure you can disconnect them from the target MCU, despite what I thought above. Apologies for that. At least you can't do it easily.

SB16 and SB17 aren't what you want.

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Yes the board I'm using is the NUCLEO-H745ZI-Q, regarding the power of my custom board, I've checked the voltage it's 3.3V to MCU, SWDIO on PA13 and SWCLK on PA14.

On the NUCLEO-H745ZI-Q side I can see that T_SWDIO and T_SWCLK are connected to MCU through a level shifter U10, is unsoldering this component will resolve the problem ?

Thank you for your feedbacks.