My Arduino Uno was working fine. Now every time I try to upload a sketch, I receive the error "programmer is not responding".
Judging from the similar problems others have had when their sketches had too much serial I/O in the loop(), I think my problem is that my loop() contains too much delay (about 2 seconds). I think the loader tries to talk to the board, but gives up in less than 2 seconds.
So to be happy in the future, I think I need to make sure the loop() time is always short - for example, under 1 second.
Can anyone with more experience with the Arduino Uno say whether this is true (that a loop() that takes more than a few seconds will cause "programmer is not responding" errors)?
Thanks.