I've recently begun using the Pololu A-Star 32U4 board. I believe this is also similar to the SparkFun Pro Micro (32U4 processor). I read the long exchange with FrankP and am wondering if there are some similarities in the probs working with that processor and VM.
Pololu has a compatibility library that allows the Arduino IDE to be used with their board. It is first installed thru the IDE and adding the link in the IDE Preferences (
https://files.pololu.com/arduino/package_pololu_index.json) for additional boards.
And it all works well with the Arduino IDE.
So next I get Visual Studio 2017 working, and have the latest VM installed, and all seems well until I try and compile a test script that does NOT have the VM debug enabled. I get the weird msg below (which I posted earlier).
Now my long project is close to being done and so I wanted to compile with no debugger - so I turned it off, and low and behold that same weird message shows up! AND - the upload sometimes works, sometimes doesn't.
I've gone to Pololu about this and they say they have never seen such a message and are saying it must be VM. After the problems FrankP had with a 32U4 I'm wondering if there is something about the boot loader for the 32U4 use that makes VM unhappy.
Currently I'm running in VS2017 in debug mode, but have to go to the straight Arduino to do a no-debug compile. Which isn't so bad but it does seem something is up.
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Compiling 'ConstantSpeed-avr' for 'Pololu A-Star 32U4'
Program size: 8,224 bytes (used 29% of a 28,672 byte maximum) (0.85 secs)
Minimum Memory Usage: 447 bytes (17% of a 2560 byte maximum)
Uploading 'ConstantSpeed-avr' to 'Pololu A-Star 32U4' using 'COM10'
The upload process has finished. via 'COM11'
Connecting to programmer: .
Found programmer: Id = "CATERIN"; type = S
Software Version = 1.0; No Hardware Version given.
Programmer supports auto addr increment.
Programmer supports buffered memory access with buffersize=128 bytes.
Programmer supports the following devices:
Device code: 0x44