Arduino Pro Mini (clone) stopped working and won't upload

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1

Arduino Pro Mini (clone) stopped working and won't upload

Several months ago, I bought an Arduino Pro Mini 5V 16MHz with the ATmega 328p, a clone version. I uploaded a PWM to PPM conversion software, and everything worked perfectly. The Arduino read the 6 input signals from ports A0 to A5 and sent them through port 2. Today, I went to test it, and out of nowhere, it stopped working. The Arduino is mounted on a PCB, so I haven't changed any connections since the first day it worked. Now I'm trying to upload the software again with an FT232RL, just like I did the first time, and I'm getting this error:

avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 1 of 10: not in sync: resp=0xec
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 2 of 10: not in sync: resp=0xec
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 3 of 10: not in sync: resp=0xec
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 4 of 10: not in sync: resp=0xec
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 5 of 10: not in sync: resp=0xec
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 6 of 10: not in sync: resp=0xec
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 7 of 10: not in sync: resp=0xec
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 8 of 10: not in sync: resp=0xec
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 9 of 10: not in sync: resp=0xec
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 10 of 10: not in sync: resp=0xec
Problem uploading to board.  See https://support.arduino.cc/hc/en-us/sections/360003198300 for suggestions.

I have already checked all the connections and made sure the FT232RL is working (I tested it by uploading another software to a Bluepill, and everything is fine).

2

Was it mounted in the PCB when you originally programmed it?

There was a selection between old bootloader and new bootloader for one of the 328P based boards. I think it was the Nano but that also used a 328P. You could try that just in case.

3

The Pro Mini has 4 options; clock (2x) and processor (2x). So indeed worth a try.

The Nano has three options; 328P, 328P (old bootloader) and 168.