AnsweredAssumed Answered

iMXRT JTAG pins floating

Question asked by Anuj Tanksali on Feb 5, 2020
Latest reply on Feb 16, 2020 by Kerry Zhou



I am using iMXRT1064 device on my prototype board. 

Facing an power up issue with the board.


I perform the following steps


1) Connect the PE micro Multilink Universal debugger (using 10 pin jtag connection)

2) Power on the board using PC usb port

3) Program the board  (test demo software LED blinky)

4) Power off the board

5) Remove the PE micro Multilink Universal debugger 

6) Again power on the board. board does not start and no led blink is observed

7) Connect the PE micro Multilink Universal debugger when board is in power on state. Board LED starts blinking.


after point 6 if i keep the board aside for maybe around 2 hours and then again power it up then the board starts.

To immediately start the board after it is programmed i have to connect the debugger. without the debugger the board does not start


Why could be the issue?


As per schematic the JTAG pins are all floating. is there any pull up/pull down configuration that is needed in firmware.