jpsganesh
Full Member level 3

I made a custom HW with minimal support for USB factory bootloader using EFM8UB31F40G-A-QSOP24. It's USB powered device, before connecting to USB, to enter bootloader mode I'm connecting P2.0 (C2D) to GND. (and RSTb (C2CK) PIN pullup to 5v)
When I connect it to my PC (laptop) I can see th device connected as HID in device manager.
I took a example program to blink a LED. Converted hex to EFM8 file using hex2boot.exe and trying to download this EFM8 file to deice using factory bootloader using efm8load.exe. But it says "ERROR: Unable to open port!"
Please refer the attached screenshot1, my laptop has some other HID device connected. Is that the problem for not programming? referring AN945 document, it says only one HID device should be connected.






When I connect it to my PC (laptop) I can see th device connected as HID in device manager.
I took a example program to blink a LED. Converted hex to EFM8 file using hex2boot.exe and trying to download this EFM8 file to deice using factory bootloader using efm8load.exe. But it says "ERROR: Unable to open port!"
Please refer the attached screenshot1, my laptop has some other HID device connected. Is that the problem for not programming? referring AN945 document, it says only one HID device should be connected.





