Problem Reading Input Pins

Development Boards Arduino
1

Hi. While I’m new to Arduino I’m fairly experienced with microcontrollers, and I’ve reason to believe the Arduino Uno I received as part of this SIK is incapable of reading at least some of its I/O pins.

I began using the SIK guidebook as an introduction to the Arduino IDE via the “Blink” sketch - which worked fine.

I then tried some of the sketches in Jeremy Blum’s “Exploring Arduino” book. Based upon LED responses, the output pins tested seemed to work fine. However, as soon as the LED output depended upon a switch input (e.g. a switch debounce sketch or one which simply uses an LED to indicate whether the switch input is high or low (I used a DVM to verify the switch’s 0-5V level change at the Arduino inputs) the sketches do not work. The LED output does not change state with switch changes. I tried pins 2, 3, and 4 using pinMode() to set them as inputs. I’ve directly imported Jeremy’s code to be certain I don’t have any syntax errors (his sketches all compile fine).

Please feel free to suggest alternate tests, but the ones I’ve tried indicate that my Uno does not respond to logic level changes on at least three of its I/O pins.

Thanks! - guy

2

Hi guy,

We don’t carry the “Exploring Arduino” book so I can’t help with that code but if you have the SIK, a good test to try confirming a problem with the I/O pins would be the [Simon Says Circuit. Try that example since it uses most of the I/O pins on the Uno/RedBoard as inputs and outputs.](https://learn.sparkfun.com/tutorials/sparkfun-inventors-kit-experiment-guide---v40/circuit-2c-simon-says-game-)