I realize this generic error has been asked about lots of times before, but I have been unable to find an answer that works for me.
I have a bunch of pro mini's that I program with an FT232RL. It works perfectly fine for some time, but eventually it stops working and I get the error:
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 1 of 10: not in sync: resp=0x00
Using the same FT232RL on an unused pro mini still works fine. Burning a new bootloader through an Uno as ISP works fine, as well as uploading code to the pro mini that way, but even after burning the bootloader the FT232RL does not work on that pro mini again.
I have experienced this exact behavior on three different pro minis in a row now. Is there any sort of factory reset-ish thing I can do other than the bootloader to try to get these back to square one?