Arduino USB2Serial Programmer/Pro Mini

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1

I sure could use some help. I am in day 4 of trying everything I can find to fix this problem.

I have a Arduino USB2Serial programmer. The latest Arduino IDE 2.3.6 installed on a Windows 11 laptop. Also tried using my Windows 11 Desktop.

I am trying to program a Pro Mini clone. I have 3 here.

One has been programed it the past, two are new, never written to.
No matter what I try, I can not get any of them to program.

When I plug the USB2Serial to the laptop, device manager shows it as Arduino USB Serial Light Adapter(COM7) using driver Arduino Srl (www.arduino.org)

If I use the Serial Monitor and loop the Tx and Rx pins and type a word, it shows in the monitor.

I get this error message:

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 "C:\Users\Herb's Laptop\AppData\Local\Arduino15\packages\arduino\tools\avrdude\6.3.0-arduino17/etc/avrdude.conf"

     Using Port                    : COM7
     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=0x89
User abort

Can someone help me with resolving and fixing what ever is broken???

I will try to provide any further information that may be needed.

2

Have you tried all the Tools/Processor options?

I use an FTDI programmer, know nothing about what you have, are you sure it works?

3

Yes

4

Then try all the processor combinations. Is this your board?

Screenshot 2025-11-03 at 10.57.38
Screenshot 2025-11-03 at 10.57.381146×516 81.8 KB

5

That is the download rate for an 8MHz 3.3V ProMini. Is that what you have?

Is your usb to Serial adaptor dropping the voltage to that level, or is it 5v?

6

Here is the link to the programmer I am using.

https://docs.arduino.cc/retired/boards/arduino-usb-2-serial-micro/

I have tried every Processor. And most all of the Programmer selections.

The two 328 selections give the 57600 error, the two 168 give a 19200 error.

7

Sorry, I have never used that adapter and have no idea re the 57600 and 19200 errors that sound like baud rates.
May I suggest you buy a FTDI programmer similar to the following. Of course you will also have to install the driver from FTDI

Screenshot 2025-11-03 at 12.03.26
Screenshot 2025-11-03 at 12.03.261916×938 186 KB

8

Do you have he rst pin connected as shown here?
https://docs.arduino.cc/retired/getting-started-guides/ArduinoMini/

9

Don’t need a new programmer. The one I have works on the 5V 168 pro mini’s I have. But does not seem to work oh the 5V 328 ones.

I am beginning to think the 328’s have a boot loader problem.

10

Pins are connected correctly. Works with 168 pro mini’s but not the 328 ones..

11

What is more likely, every 328 has a problem, or your procedure is incorrect?

12

Well obviously there is some difference between the 168 and 328 versions you have