The DTR line is low when the board isn't connected to the clone and a terminal window in the IDE is open. The DTR line is high @3.53~4ish volts when connected to the clone.
I have a few of these logic level converters and wired one up on a breadboard between the clone and the CP2103 boards. To my surprise, I'm getting serial data from the clone.
The clone is running a blink program with serial prints of the current state of the LED, and I'm seeing those prints in the serial monitor.
Attempting to upload code to the clone gives me basically the same error messages as before.
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:\Program Files (x86)\Arduino\hardware\tools\avr/etc/avrdude.conf"
Using Port : COM4
Using Programmer : arduino
Overriding Baud Rate : 115200
avrdude: stk500_getsync() attempt 1 of 10: not in sync: resp=0x6c
avrdude: stk500_getsync() attempt 2 of 10: not in sync: resp=0x65
avrdude: stk500_getsync() attempt 3 of 10: not in sync: resp=0x64
avrdude: stk500_getsync() attempt 4 of 10: not in sync: resp=0x20
avrdude: stk500_getsync() attempt 5 of 10: not in sync: resp=0x2d
avrdude: stk500_getsync() attempt 6 of 10: not in sync: resp=0x20
avrdude: stk500_getsync() attempt 7 of 10: not in sync: resp=0x6f
avrdude: stk500_getsync() attempt 8 of 10: not in sync: resp=0x66
avrdude: stk500_getsync() attempt 9 of 10: not in sync: resp=0x66
avrdude: stk500_getsync() attempt 10 of 10: not in sync: resp=0x0d
avrdude done. Thank you.
An error occurred while uploading the sketch
But at least now, I'm getting some response from the CP2103.
I hope my info helps and a lot of thanks to you for helping me on this project.
Randy