"Impossible to send message" when using too many pins

[Sean Bouchard Bloom]

Windows 10 / Unity 2018 / Uduino 2.1.0 / Arduino Uno

I'm running into what seems like a very strange issue. I'm using 6 analog pins for input (A0 - A5) and three digital pins for output (9, 11, and 13). When I run my game, I get all kinds of strange behavior. Sometimes one of the input pins will not get any input; sometimes one of the output pins will stop working. I also get this message repeated continually in my console:

Impossible to send the message <color=#4CAF50>b 9,s 9 0,s 11 0,s 12 0,s 14 2,s 15 2,s 16 2,s 17 2,s 18 2,s 19 2 </color> to <color=#2196F3>[\.\COM3]</color>: System.IO.IOException: The semaphore timeout period has expired.

I've discovered that if I remove any one pin from either the inputs or outputs, everything else works exactly the way that I expect it to. It doesn't seem to matter which pin I remove, or whether it's an input or an output. It's just when I try to run my game using all six inputs and three outputs that I get the message and strange behavior.

I played around a little with adjustments to the read and write timeout values in Uduino. It didn't seem to make a difference, but I didn't experiment extensively. Do you have any idea what might be causing this?

[Marc Teys]

Have you try to increase the read timeout and the write timeout under the Uduino prefab > Advanced > Serial settings ?