Cow Pi

The Cow Pi is the latest product line from Eclectic Electronics [1] and is guaranteed to bring you minutes of fun. Whether you need a 4-function calculator to count your terror bird eggs before they hatch, an electronic combination lock to secure your wildly-dangerous experimental robots, or a motion alarm to protect yourself from zombie gourds, using a Cow Pi development board is your best option.

• Hardware
  • Microcontroller Boards
  • Input Devices
  • Output Devices
• CowPi Library
  • Configuration / Initializing the Board
  • Input Functions
  • Output Functions
  • Pin Interrupts
  • Example Code
• CowPi_stdio Library
  • Configuring stdio File Streams
  • Special Considerations
  • Other Functions for Display Modules
  • MAX7219-driven Seven-Segment Display
  • MAX7219-driven LED Dot Matrix Display
  • HD44780-driven LCD Character Display
  • Morse Code on Output Pin
  • Communication Protocols for Display Modules
  • Theory of Operation
  • Functions for Direct Control of Display Modules
• Microcontroller-Specific Details
  • ATmega328P (Arduino Nano, Arduino Uno R3)
  • RP2040 (Raspberry Pi Pico)
• Expansion Options
• Cow Pi Physical Assembly Instructions
  • Cow Pi mark 1e Construction Instructions (Arduino Nano form factor, SPI communication)
  • Cow Pi mark 1f Construction Instructions (Arduino Nano form factor, I²C communication)
  • Cow Pi mark 3c Assembly Instructions (Raspberry Pi Pico form factor, SSD1306 OLED graphic display via I²C communication)
  • Cow Pi mark 4b Assembly Instructions (Raspberry Pi Pico, SSD1306 OLED graphic display via I²C communication)
• Troubleshooting Connections to Arduino Nanos
  • USB Driver Problems
  • ATmega328P vs ATmega328PB
  • Other Uploading Issues
• Changelog
  • [202403]
  • [202401]
  • [202309]
  • [202308]
  • [202301]
  • [202208]
  • [202201]
  • [202108]
• Acknowledgements

Cow Pi documentation ©2021–23, Christopher A. Bohn, and licensed under the CC BY 4.0 License.

Cow Pi hardware designs ©2021–23, Christopher A. Bohn, and licensed under the CERN-OHLP v2 License.

CowPi library ©2021–23, Christopher A. Bohn, and licensed under the Apache 2.0 License.

CowPi_stdio library ©2022–23, Christopher A. Bohn, and licensed under the Apache 2.0 License.

[1]

Eclectic Electronics is a joint subsidiary of The Pleistocene Petting Zoo, a Limited-Reality Corporation, and of Babbage’s Analytic Engines, a Frankly-Figmentary Partnership. [2]

[2]

These are fictional companies imagined by Christopher Bohn for course assignments. You didn’t think they really existed, did you? Christopher Bohn, however, really does exist and can be contacted at bohn@unl.edu.