Woody brings class to the world of RPN calculators

RPN (Reverse Polish notation) is a technique for writing or coming into mathematical calculations whereby operators come after operands. As an example, to calculate the product of three and 4, you’ll kind: 3, enter, 4, enter, multiplication. That is unfamiliar to most of us, however was frequent for Hewlett-Packard’s early digital calculators and continues to be utilized in some programming languages, like Forth. Some folks desire RPN calculators and this one, referred to as Woody, is essentially the most lovely of the bunch.

Woody is a reasonably easy RPN calculator, which was its whole objective. Many of the RPN calculators accessible are sophisticated scientific or graphing calculators. Shiura needed primary calculator performance, however with RPN. It is usually beautiful. The enclosure is a strong chunk of walnut wooden, which was milled on a CNC router. Aside from a big energy swap on the again, the one options are 19 keys and a dot-matrix type LCD display screen.

An Arduino Nano board reads the important thing presses, does the mathematics, and outputs the outcomes to the LCD show. The keypad got here from a small numeric keyboard, which Shiura hacked to watch the keyboard matrix immediately. The Arduino connects to the display screen by way of I2C. Energy comes from a pair of AA batteries via a DC-to-DC converter. The result’s a surprising calculator with all the advantages of RPN.