reusing the jtag pins

nikhil23 · ‎2008-12-08

Posted on December 08, 2008 at 09:10

nikhil23 · ‎2011-05-17

Posted on May 17, 2011 at 12:55

Due to design limitation I have to use one of the jtag interface pin(JTCK) as input, but i cannot configure it as any other normal pin, not even as output. According to datasheet it is input pull down at reset, but how can i control it as any other GPIO pin? What should be procedure for make it behave as normal GPIO.

I do not have to use debug and is using bootloader, so can spare jtag interface.

I use following Configuration for JTCK pin PA14

as input-> pull up/pulldown

as output-> both pushpull and open drain.

16-32micros · ‎2011-05-17

Posted on May 17, 2011 at 12:55

Hi,

You can refer to ST FWLib :

http://www.st.com/mcu/modules.php?name=mcu&file=familiesdocs&FAM=110#Firmware

http://www.st.com/stonline/products/support/micro/files/um0427.zip then you can find an example under ''FWLib/examples/GPIO/JTAG_Remap/'' Folder

Here attached the main.c

Hope thsi helps you 🙂

Cheers,

ST1-32.

nikhil23 · ‎2011-05-17

Posted on May 17, 2011 at 12:55

thanks,

it works, that time i forget to remap/disable the Jtag :D