I had some difficulty remembering how to set the Arduino IDE to upload sketches to a Pro Mini clone with an ATmega328P chip so I’m keeping a record this time.

Wiring: (TTL) DTR/RTD/TXD/VCC/GND -> (ProMini) DTR/TXD/RTD/VCC/GND 
Board: Arduino Uno
Programmer: AVR ISP
Tip: don't need to key the reset-button during upload if DTR is set.

I default to Baud 9600 for serial connections but the IDE loads at 56700(?) baud. I probably didn’t think serial was successful because I had the baud rate wrong.

(Hi future self. By the time you’ve read this, you’ll probably have a successful serial connection using “Arduino Pro or Pro Mini, ATmega328P” settings. Serial connection will work on those settings but uploads will fail.)

Common IDE error responses:

avrdude: stk500_getsync() attempt 1 of 10: not in sync: resp=0x00
avrdude: stk500_getsync() attempt 2 of 10: not in sync: resp=0xe0
avrdude: stk500_getsync() attempt 3 of 10: not in sync: resp=0xe0
avrdude: stk500_getsync() attempt 4 of 10: not in sync: resp=0x00
avrdude: stk500_getsync() attempt 5 of 10: not in sync: resp=0x00
avrdude: stk500_getsync() attempt 6 of 10: not in sync: resp=0x00
avrdude: stk500_getsync() attempt 7 of 10: not in sync: resp=0x00
avrdude: stk500_getsync() attempt 8 of 10: not in sync: resp=0xe0
avrdude: stk500_getsync() attempt 9 of 10: not in sync: resp=0x00
avrdude: stk500_getsync() attempt 10 of 10: not in sync: resp=0x00