There are two different button configurations described below.
- The RPi.GPIO uses 1k resistors connected to the 3.3v rail
- The CircuitPython code uses software pull ups.
Important things to note:
- The Adafruit Pi Cobbler is being used; for the A+/B+/Pi 2, the Pi Cobbler Plus or the Pi T-Cobbler Plus should be used with any Raspberry Pi after version 1.
- The Adafruit Clear Full sized breadboard is being used
- (3) 10k pull-up resistors
- (3) Momentary push-button switches
- GPIO pins 23, 24, and 25
- Cobbler 3.3v rail is tied to positive breadboard
- Cobbler gnd rail is tied to negative breadboard
Note that we are not using pull up resistors and do not need to connect to the 3.3v rail. We can do direct pin to button and button to GND connections with CircuitPython configuration.