After seeing an Arduino Project Hub article, I purchased a handful of NSA1166 bubble LED displays from Jameco and decided to build a retro calculator.

The calculator uses an MSP430G2553 microcontroller and ICM7228 LED driver along with a generic 4x4 matrix keypad.

To make the project as small as possible and to simplify the wiring, I created created a PCB design and ordered it from OshPark.

Due to limitations of my keypad and the display (6 characters with a single fixed decimal point), the calculator only supports limited functions and integer math.

The Eagle BRD and SCH files can be found in the hardware folder, along with a PDF of the schematic.

The calculator uses my matrix keypad library and ICM7218 LED driver library.

• Arduino Project Hub article
• NSA-1166 datasheet
• NSA-1166 devices at Jameco
• MSP430G2553
• ICM7228
• Schematic
• Library written specifically for NSA1166, without using discrete controller IC
• Vintage Novus 650 Mathbox calculator that used the NSA1166 display, including interior pictures

The software and other files in this repository are released under what is commonly called the MIT License. See the file LICENSE in this repository.