Cannot load code to Arduino Pro Mini (Programmer not responding)

Using Arduino Avrdude, stk500, Bootloader issues
1

I cannot upload any sketches to the Pro Mini. I am using Arduino Uno for connecting Pro Mini to my computer.

Verbose log:

avrdude: Version 6.3-20190619
         Copyright (c) 2000-2005 Brian Dean, http://www.bdmicro.com/
         Copyright (c) 2007-2014 Joerg Wunsch

         System wide configuration file is "/Applications/Arduino.app/Contents/Java/hardware/tools/avr/etc/avrdude.conf"
         User configuration file is "/Users/yagizhanisik/.avrduderc"
         User configuration file does not exist or is not a regular file, skipping

         Using Port                    : /dev/cu.usbmodem14301
         Using Programmer              : arduino
         Overriding Baud Rate          : 57600
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 1 of 10: not in sync: resp=0x00
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 2 of 10: not in sync: resp=0x00
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 3 of 10: not in sync: resp=0x00
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 4 of 10: not in sync: resp=0x00
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 5 of 10: not in sync: resp=0x00
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 6 of 10: not in sync: resp=0x00
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 7 of 10: not in sync: resp=0x00
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 8 of 10: not in sync: resp=0x00
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 9 of 10: not in sync: resp=0x00
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 10 of 10: not in sync: resp=0x00

avrdude done.  Thank you.

Problem uploading to board.  See http://www.arduino.cc/en/Guide/Troubleshooting#upload for suggestions.

System Information:

OS: macOS Catalina 10.15.4
Arduino IDE: 1.8.12

Connections:
Mac <-USB-> Arduino UNO (without ATMega Processor)

Arduino UNO Pro Mini (5V)
TX TX
RX RX
5V VCC
GND GND
RESET DTR

It rarely flashes, but mostly fails.

2

I'm suspicious of the reset signal. Try this:

Sketch > Upload

Watch the black console window at the bottom of the Arduino IDE window. As soon as you see something like this:

Sketch uses 444 bytes (1%) of program storage space. Maximum is 30720 bytes.
Global variables use 9 bytes (0%) of dynamic memory, leaving 2039 bytes for local variables. Maximum is 2048 bytes.

press and release the reset button on the Pro Mini.

When you do the manual reset, does the upload work every time?

3

Unfortuately, didn't worked.

But also I think reset is not working on the Arduino, too. Before pressing the reset button on the Pro Mini, the voltage in the reset pin is around 1 Volt, after pressing the button nothing changes. On my other Arduinos, this voltage is around 5 Volts and after pressing the button it decreases to 0.01V.

4

How are you "using the Arduino Uno to connect it to your computer"?

5

DrAzzy:
How are you "using the Arduino Uno to connect it to your computer"?

There is no USB port on Pro Mini. So, I'm using UNO as a USB-Serial converter.

6

Where did you get the Pro Mini? Possibly it has no bootloader, or an incorrect bootloader. Can you verify that the Pro Mini has an atmega328 and not an atmega168?

7