simple_rpn_calc

Very simple code of RPN calculator for Arduino

What's this?

I made a keychain type RPN calculator like a toy with Arduino.

The aim of this calculator is "anyone can use RPN". So the function is very simple.

• There are only 16 keys, numerals(0-9), operators(+-*/), decimal point(.), and Enter.
• Integers can only display up to 7 digits.
• Decimals can only display up to 2 digits.
• Display is in fixed-point mode only. If it overflows, an error will occur.

As long as you know RPN, you can use it easily.

Please also see the following article (in Japanese). https://dailyportalz.jp/kiji/RPN-calculator

about Hardware

Required parts:

• Arduino compatible microcontroller (ex. ProMicro)
• 0.91 inch OLED display
• 16 push switches and diodes
• Power switch
• Battery holder

The key matrix circuit is assumed as follows. To eliminate the resistor, this configuration utilizes the Arduino's internal pull-up resistor.