I'm running Arduino 1.8.12 under Windows 10.
I'm trying to develop an application for an Arduino Nano
At first try I got a report that AVRdude could not communicate with the arduino every time, despite being set to the right COM port (COM5).
I updated the FTDI drivers and this seemed to have sorted it...
But what happens is that for every new session I get the 'AVRdude could not communicate' error, until after around half a dozen attempts or more, it suddenly starts working, and appears to keep working.
Unplug/reattach the Nano makes no difference.
No other program is using the com port, the USB lead is good.
I absolutely HATE intermittent issues like this, can anyone suggest what might be the issue?
Update: Just tried again, with computer restarted and everything connected afresh.
It took seven attempts (simply clicking the upload button after each failure) to get the sketch to upload.
Is there an 'auto retry' feature?
OK, I lost patience and after much playing I found an apparent solution.
But it wasn't...
If you posted the exact text of the error message, rather than a vague, qualitative description of it, I might have been able to provide more input. Two errors that look very similar to an inexperienced user may mean something completely different to an expert.
That description of the problem and solution doesn't add up.
OK, fair enough!
I have found the real issue, but for completeness:
The error messages are:
Using Serial Monitor:
Board at COM5 is not available
Using AVRdude:
** Using Port : COM5**
** Using Programmer : arduino**
** Overriding Baud Rate : 57600**
avrdude: ser_open(): can't open device "\.\COM5": The system cannot find the file specified.
The actual cause is that I had Ultimaker Cura open. It grabs all USB-com ports on the assumption that they are 3D printers.
"All Your COM PORT Are Become Ours"
Alledgedly, this can by prevented by disabling the USB Print plugin in Cura, in practice this hasn't worked for me and the only solution I have found so far is to close Cura, which is 100% reliable.
A real pain as Cura is a real slow-start program unless it manages to get cached, but it's an issue with Cura not AVRdude/Arduino.