'No target connected' - again

[michaelkotthaus9132]

Posted on March 19, 2013 at 16:05

I have been using the STM32F4 Discovery board for a short time with no problems (using SWD via mini-USB) when I suddenly got the 'No Target Connected' error. Reading the forum I tried the fix of BOOT0 high and BOOT1 low during power-up. I am using Keil uVision4 and pressing 'LOAD' I get :

Load ''...myprog.AXF'' Erase Done. Programming Done Verify OK If I now disconnect BOOT0 from Vdd the code and press the reset button the code runs as you would expect. My problem is I have to repeat the  power down - BOOT0 to Vdd - power up - load - disconnect BOOT0 - reset sequence every time. How to I return the board to the state it was in before I messed it up ? Thanks

[Tesla DeLorean]

Posted on March 19, 2013 at 16:50

How to I return the board to the state it was in before I messed it up ?

It's your software not the board. Fix that and it won't happen. What would mess it up? Well reconfiguring the JTAG/SWD GPIO pins, spinning in WFI loops of going into low power modes, DMA operations, etc. Basically look at what your code is doing for the first ten or hundred thousand cycles.