Howto:Build your own Panel or Cockpit - Prototype for Numeric Displays using Maxim MAX7219

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Numeric Displays using Maxim MAX7219

This prototype project demonstrates the use of the Maxim Max7219 chip to display numeric data and explore power requirements for these displays. Numeric Display Prototyping Goals

  • Confirm the suitability of modules containing 4 MAX7219 chips
  • Stress test numeric displays of varying physical sizes
  • Determine power requirements for various quantities of modules, display types and digits

Numeric Display Parts List

1 Raspberry Pi
1 Raspberry Pi Breadboard Connector
1 Breadboard & Jumper Wires
3 4 module boards, each module containing 4 MAX7219 chips
8 5 digit 7 segment displays with decimal points
additional 4 digit 7 segment displays with decimal points

Numeric Display Software

  • NodeJS
  • Max7219Test
    • Initialize 8 Maxim MAX7219 modules
    • Drive 8 Cascaded MAX7219 modules with 5 digit displays each
    • Test Routines

Numeric Display Construction I purchased a module on AliExpress containing 4 MAX7219 modules Numeric Display Tests & Results

display of numbers 0-9 in each digit in each of 8 banks of digits
Power Supply - Will Raspberry Pi Power Not be enough?
* All digits the same cycling through 0-9
* All digits 0-9 in order with using all digits
* All digits 0-9 in order using all digits cycle decimal point on each digit.
* Power Requirements for All Digits 8 with decimal points turned on for each digit.