SWD on STM$32f4 discovery

[arunashok]

Posted on December 16, 2011 at 13:12

Hi all,

 I am trying to program the discovery board of stm32f4 using SWD via the Cn3 connector. Does anyone have any experience in that.. Arun

[raptorhal2]

Posted on December 16, 2011 at 15:11

The board isn't set up to do that conveniently. The SWD connector is designed for programming an external MCU by connecting it's SWD connection to the Discovery SWD. Your PC connection is then to the USB connector CN1, and the Discovery is being used as a pass-through. Removing the CN3 jumpers keeps the Discovery F4 processor from messing up communication with the external MCU.

If you really want to program the Discovery via a SWD connection, you will have to use pins PA13, etc., and possibly even supply a separate power and ground to the board. The F4 datasheet has pinout definitions you will need to do this. Cheers, Hal

[Tesla DeLorean]

Posted on December 16, 2011 at 17:36

Although CN3 would represent a good injection point for an external SWD programmer, you'd obviously want to hook up a ground, and maybe the NRST

[raptorhal2]

Posted on December 17, 2011 at 22:45

Clive is correct. You will also need to connect power. 5V will be needed to get 2.5V for the Cirrus chip. Otherwise, it looks like 3V regulated will do.

Cheers, Hal

[arunashok]

Posted on December 30, 2011 at 11:58 Hey... Thanks all.. Sorry for the late reply though.. I had a separate developement board and I had to do the programming via SWD, so i guess it would similar to Discovery. I managed to do it finally.. Thanks for the inputs Arun