2025-08-14 10:30 AM
Hello... I'm learning to use an external ST-Link to debug the F446ZE Nucleo using SDW. Can anyone advise on how to connect the SDIO, SDW pin on the Nucleo board to the external ST-Link v2? Additionally, what settings should I configure in CubeIDE to use the ST-Link v2? I also have an ST-Link v3. Any advice on ST-Link v3 is also welcome, thank you.
2025-08-14 10:54 AM
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.
2025-08-14 3:50 PM
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).
2025-08-14 5:50 PM
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.
2025-08-15 8:06 AM
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
2025-08-15 1:09 PM
"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..
2025-08-15 1:18 PM
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
2025-08-15 2:44 PM
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!
2025-08-15 6:14 PM
thanks Pavel, i know H743 nucleo has an embedded STLink. I wana learn to use ext. STLink v3 on H743 so that when my custom board is ready, i can test it on the custom board.
Can anyone advise?
2025-08-15 6:37 PM
What about CN4.1? Do you need to connect the CN4.1 (3v3) to the ext. STLink v2 ? (show below)