MINI-M4 Unable to find device: USB HID Bootloader

[dchang735]

Hi,

I have MINI-M4 for STM32 that was working and suddenly it stopped working. I am using mikroBootloader v2.1.0.0 and it does not detect the USB link. The green LED does turn on when I plug it into the USB but my computer can't detect/connect the MINI-M4 anymore. I am using a Windows 8.1 desktop. I have tried other USB ports and it still does not work. I used a spare/new MINI-M4 and that works perfectly fine.

Any ideas?

Thanks,
Derek

[aleksa.jovanovic]

There is a possibility that you've messed up the bootloader in the chip.
Could you reprogram the bootloader HEX in the M4 ?

Best regards,
Aleksa

[dchang735]

Can you give steps for that?

I can't even get my computer to detect the Mini-M4 anymore. Otherwise uploading the USB HID Hex would probably solve this issue. But as of now I am pretty much unable to detect the USB link to the Mini-M4. I have in total 6 Mini-M4s and it has happened to 2 of them. The other 4 work perfectly fine still.

Thanks,
Derek

[aleksa.jovanovic]

You need a programmer for STM.
This is the connecting scheme for our mikroProg for STM with MINI M4.
http://www.mikroe.com/mikroprog/stm32/

Best regards,
Aleksa

[dchang735]

Thanks! I uploaded the USB hex again and it works great!