When a reading is wrong

What it does, and where to look

Pick what you are seeing. The board rings where to look, and the verdict says why.

Print the number first

Nearly every fault shows in the raw reading, so run the first read sketch before anything else and push each way. With the right wiring an Uno prints about 0, 111, 182, 273, 444 and 1000 thousandths for nothing, up, press, left, down and right; an ESP32 prints right a little under 1000, often about 940.

• All 0: VCC is missing, or SIGNAL is on the wrong hole.
• Random, with nothing pressed: SIGNAL is not reaching the pin read.
• The right order, but every number about two thirds of the book's: an Uno with VCC on 3V3.
• The right numbers, the wrong names: the block is held another way round. The names are for the header on the left.
• Extra pushes when letting go: the sketch trusts every reading.
• A press nobody made: a diagonal from left to up, which reads as a press.

The one that is not a fault

That last one is the ladder working as designed. Up and left together settle between the press's level and left's, on the press's side of the line; two at once shows why. A menu that must not select by accident should ask for the press to be held a little longer than a thumb's roll.