Features:

  • All Through Hole parts. (easy to handle and solder)
  • Runs about 4 to 5 times faster than the original.
  • Memory registers 65 (Same memory as the original).
  • Continuous memory (Memory is not lost when calculator is turn off).
  • Auto power off
  • Runs on a single ATMEGA328 8 bit microcontroller running @ 8MHz (same as Arduino Uno)
  • Speaker for audible keypress feedback
  • 192x64 lcd display
  • Display Backlight
  • Has a real time clock. (Uses a 32.768KHz crystal)
  • Uses a single CR2032 3V battery.
  • Power consumption: 1µA off, 350µA idle, 3mA working (this is with speaker and backlight off)

The 3D printed case is available at thingiverse.

And the keyboard overlay is available here:

The ATMEGA328 is located beneath the display:

Youtube video: