I don't know where you guys stand on people asking questions regarding clones but I thought it's probably worth a go seeing as I don't really know where else to ask.
I recently purchased a Nano clone and for some reason the serial monitor is not working correctly.
The ebay listing says that the board runs at 32Mhz and from looking at the official Arduino nano spec I can see that the genuine board runs at 16Mhz. So i thought it might be a BAUD rate issue but I've tried a whole range of BAUD rates including 4800, 9600, 19200, 38400 and 57600 but none seem to work. Obviously I've set the BAUD rate in Serial.begin() and then Selected the corresponding from the drop down menu in the Serial monitor each time.
The problem that I'm getting is just a display of reversed question marks which scroll horizontally across the screen... even though I used Serial.println in my sketch so it should really be scrolling vertically.
the setup is...
just a potentiometer with the wiper attached to A0 and the left and right pins attached to ground and 5v
Serial.begin(9600); //tried various different BAUD's
pot = analogRead(A0);
so as you can see, you couldn't really get any simpler than this. Therefore I'm beginning to think I might have picked up a dodgy clone. What does people think?
Also... I had an issue uploading sketches to the board to begin with but then I selected ATMEGA328P (old bootloader) from the processor menu and then it worked. I know this because I ran a square wave with tone(); and controlled it's frequency with a potentiometer and measured it with my scope and everything worked correctly.
Just in case this helps with Nano clones. I have just been given a box of 5 Nano clones advertised as :-
[MINI carte de développement PCB USB Nano V3.0 CH340G FT232RL 5V 16M, Micro-contrôleur pour arduino].
Non of them initially worked but after much brain wrenching, finally they now all work.
I have not downloaded any new drivers or changed to any previous Arduino IDE.
I am running an iMac with Catalina 10.15.7 and Arduino 1.8.16.
In tools, I have set Board to "Arduino Nano". Processor to "ATmega328P old boot loader".
Port to "dev/cu.usbserial-1440". Programmer to "Arduino as ISP".
I then discovered that it was necessary to "reset" the Nano after "Compiling" the sketch and before "Uploading". I think that the "reset" was the all important thing to do.
Now all 5 clones work.
Hope that this helps anyone else who maybe contemplating ****.