2011-09-01 03:48 PM
Yesterday I hooked up my STM32VL Discovery board as the 5V power source for a simple circuit (powering the STM32VL itself from USB). It worked fine. However, today the 5V pin is only supplying about 3V (and the 3.3V pin is only supplying about 2V). In addition, the red LED on the STM32VL noticeably dims when the circuit is connected (although it may have always done this; I can't really remember), Ubuntu no longer mounts the 33MB storage on the board, Windows 7 says ''one of the USB devices connected has malfunctioned'', and Keil uVision 4 cannot find the STLink.
Did I somehow break my STM32VL? Is there anything I can do at this point to restore it to full function? #5v #discovery #brick #stm32vl2011-09-01 04:52 PM
Before you abandon all hope, recheck the input impedance of your ''simple circuit''. It may have changed, dragging down the 5V.
Cheers, Hal2011-09-01 08:21 PM
I'd disconnected the circuit completely and just used my multimeter on the 5V and GND pins on the actual STM32VL board, so that can't be it.
2011-09-02 06:26 AM
2011-09-02 03:30 PM
I tried an AC-to-USB adapter/cable I had and got the same results (as when I had been powering it from a PC's USB port)... I'm not sure this is what you meant, though. Which port, the PC's or the board's, has an efuse that might not've reset? And if it's the board's, how could one reset this from a powered USB hub?
2011-09-02 03:42 PM
The PC (or hub) port would have the fuse.