Hi.
I have an ISL29125 board and a 3.3 V ProMini. I cut and re-soldered the jumper on a 5 V FTDI so I could use it with this setup. I checked the FTDI in Windows 10 Device Manager and it thinks it’s working properly. However, I can’t upload the test code for this device, or any code, to the 3.3 V ProMini. When I tried uploading the same code with a 5 V FTDI and a 5 V ProMini (without connecting the ISL29125 to this 5 V board, of course), the code uploaded with no problem. Windows tries to assign COM8 for the 3.3 V FTDI and COM7 for the 5 V FTDI, but when I try to upload through the 3.3 V FTDI the IDE error messages just say that it’s not synced and can’t upload. no matter what port I try to use.
Am I doing something wrong here? Is the converted 3.3 FTDI somehow not working even though Device Manager thinks it is?? Suggestions? Help?