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Visitor II
August 14, 2025
Question

Debugging STM32F446ZE Nucleo SWD with external ST-Link v2

  • August 14, 2025
  • 3 replies
  • 1115 views
    This topic has been closed for replies.

    3 replies

    Graduate II
    August 14, 2025

    SWDIO and SWCLK  you mean? SWD ? What's SDW, dyslexia?

    You'd need to connect directly to the respective PA13/PA14, most readily via the CN4 jumpers you'll remove to disconnect the local ST-LINK from the STM32 Target.

    You'll need to look at the schematic and probe the pins to understand which side connects to what.

    You'd need to power the ST-LINK/V2 buffers via a connection to Pin 1 VTarget on the 20-pin header.

    PB3 (SWO) and NRST are connected more directly, so might be solder bridges or traces to be cut to adequately separate the them from the on-board ST-LINK

    For CubeIDE you'll need to select the debug pod you plan on using.

    SWD20PINSTLINK.jpg

     

    Graduate II
    August 15, 2025

    "Can anyone advise on how to connect the SDIO, SDW pin on the Nucleo board to the external ST-Link v2?"

    Trying to decipher what the question is because all the terms are jumbled and mistyped/misspelled.

    Type more better..

    Super User
    August 14, 2025

    If you want external ST-Link instead of the on-board one, you likely want the V3. It is faster, easier to connect and has USB to serial interface (aka VCOM).

     

    Visitor II
    August 15, 2025

    Yes i would like to learn how to use v3, can it be used for debugging and programming? please advise the connection pin and configuration on CubeIDE, I have both the F446ZE and H743 Nucleo, albeit, the H743 nucleo has a MIPI connector for v3 ST-link..Please advise, thx.

    Super User
    August 15, 2025

    Yes V3 can be used for all that. For pinout of ST-LINKv3 please see UM2910

    Nucleo H743 already has ST-LINKv3 on board so you don't need anything else.

    Enjoy!

     

    Visitor II
    August 15, 2025

    hello.. can anyone help to decipher the SWD connector CN6 pinout? i need to know CN6 pin 1 to 6 connect to what pin eg, which PIN is SWCLK, which is SWDIO, RST ... i m using external ST-Link v2 to connect to CN6. Please advise, thx

     

    HMSEdinburge_0-1755270107377.png

     

    Graduate II
    August 15, 2025

    CN6 Exports an SWD connection, it's NOT for connecting an external ST-LINK to the LOCAL TARGET

    SN6.1 VCC being measured

    SN6.2 SWCLK

    SN6.3 GND

    SN6.4 SWDIO

    SN6.5 NRESET

    SN6.6 SWO (PB4) Serial Wire Viewer

    If you want to connect an External ST-LINK CN4 will be better

    Remove the JUMPERS to disconnect on-board ST-LINK

    CN4.2 TCK/SWCLK LOCAL TARGET Connect External ST-LINK SWCLK

    CN4.4 TMS/SWDIO LOCAL TARGET Connect External ST-LINK SWDIO

    Use CN6.3 to establish a common ground

    Visitor II
    August 16, 2025

    What about CN4.1?  Do you need to connect the CN4.1 (3v3) to the ext. STLink v2 ?  (show below)

    HMSEdinburge_0-1755308224174.png