Martin, thanks, but the current problem is not the black squares, it is trying to upload Allard's sketch to the Raduino. The current error message is "programmer did not respond." Not a contrast issue! Scratching our heads over what it is!?
On Tue, Mar 26, 2019 at 3:50 PM Martin Potter <
ve3oat@...> wrote:
Sorry if I missed your answer some where, but did you try adjusting the little blue Contrast pot on the back of the Raduino board??? ?It isn't labelled but is the only one there.
When I first powered up my v5 board, the Contrast pot needed a small adjustment to get a readable display, otherwise black squares.
