Arduino Clock Example Code

Demonstration Code for: I2C, Interrupts, external Header File, Preprocessor Commands: Defines and Conditional Compilation

---

The project is intended to server as a reference and example for:

• Accessing a module via I2C
• Using hardware interrupts and assigning functions for varying parameters
• Read and debounce button presses via hardware interrupts
• Parsing a serial stream to get user data
• Storing data in non-volatile memory via I2C
• Including and using an External Header File
• Using Compiler PreProcessor Commands - Defines, and Conditional Compilation

To maximize ease of re-use:

• The code is broken into discrete functions.
• The Functions are named by device: 7-Segment-Display, RTC, UART, and Menu.
• The code is extensively commented to make it easy to re-purpose.

Functionality

This project reads the current time from a RTC, displays it on a 7-Segment Display Module, allows external configuration of settings via buttons, and uses sound to provide user feedback.

Details:

• Set / Read current time from DS1307 module
• Displays time on 7-Segment Display
• Interrupt-driven realtime display of time
• Outputs sound via small speaker
• Use Hardware buttons to allow user settings changes

FILES INCLUDED:

Source Code:

• 'SSclockInits.h' - program header, variable inits, defines and conditional compilation settings
• 'SSclock.ino' - main program code & all functions

Datasheets: - in the "datasheets" sub-folder

• 'DS1307.pdf' - information on DS1307 real-time clock

• 'SFE-0012-DS-7segmentSerial-v3.pdf' - ORIGINAL 7-Segment Display (Sparkfun# COM-09230)

• 'SFE-0012-DS-7segmentSerial-v41.pdf' - NEW 7-Segment Display (Sparkfun# COM-09764)

  Sparkfun 7-Segment Module Versions:

  • Differ in the characters they can display, the commands they support, and brightness level
  • So conditional complication is used to set variables/defines for the proper device version
  • Make sure the appropriate device is #defined in the SSclockInits.h file (default is NEW version)

Photos - in the "photos" sub-folder

• 'photo-clock-labeled-internals.jpg' - photo of internal of clock implementation
• 'photo-clock-outside-front.jpg' - front of clock implementation
• 'photo-clock-outside-rear.jpg' - rear of clock implementation