I can't seem to get an answer to this, I use Visual GDB so I can debug fine with Visual Studio, I just can't understand what that ST Link gadget is for or how you'd use it.

https://www.amazon.com/Microcontrollers-circuit-debugger-programmer-emulator/dp/B00C7WDTLG

 

This is how Software Development system interface to processor or FPGA
type boards to do debug and programming of the boards/chips. Very
common interface these says, SWD.

Regards, Dana.

 

This is how Software Development system interface to processor or FPGA
type boards to do debug and programming of the boards/chips. Very
common interface these says, SWD.

Regards, Dana.

Thanks, this is still not quite clear.

I can debug and program my Nucleo or Discovery boards without this gadget, so why is it needed?

Is it because these development boards have an inbuilt equivalent of that gadget that is ordinarily absent from non-development versions of the boards?

 

From the Nucleo-64 User Manual (UM1724, rev 10) page 1:
"The STM32 Nucleo board does not require any separate probe as it integrates the ST-LINK/V2-1 debugger/programmer."

See if the User Manual for your board has the same sentence in it.

 

Your IDE (programming platform) communicates by sending flashing and debugging commands. The target MCU itself does not understand these commands. A separate MCU is used to interrogate these commands and then relay them in between the PC and target MCU. That is what the ST-LINK programmer/debugger does.

Every STM Discovery or Nucleo kit has this MCU on board. You can find it in a smaller package right next to the mini-USB connector.



You do not need to purchase the ST-LINK programmer/debugger.
I can show you how to program/debug your MCU in-circuit.