This article introduces CPICOM -- an emulator for CP/M 2.2 on the Raspberry Pi microcontroller.

On websites, and in hobbyist kits for Raspberry Pi and Arduino, you'll often see I2C devices connected that have different supply voltages. This is (usually) safe and, in non-critical applications, tends to work. But why?

The MAX7219 IC is widely used to control an 8x8 matrix of LED, but they can be chained to create much larger displays. This article describes how the chaining works, and how to create a driver for the Raspberry Pi Pico.

Make an "auxiliary LCD display" for a computer that displays data sent to it over a USB connection. Ready-made devices of this sort are widely available, but it's more fun to build your own.

There is a tabular method for organizing integration computations which require repeated application of the integration-by-parts formula. It is seldom taught, which is a shame: it hugely reduces the algebraic complexity of the problem.

The use of integrating factors is a well-known method for turning an intractable differential equation into an integration problem (which may itself turn out to be intractable, but we live in hope). The method is usually described in textbooks and lectures with a fair amount of hand-waving. This article attempts to...

This article describes how to do simple temperature measurement with a Raspberry Pi, and I2C analog-to-digital converter, and a thermistor.

A small step in the right direction, or political correctness gone mad?

The ease of installation and use of modern desktop Linux distributions comes at a price. I review a couple of low-complexity alternatives to mainstream Linux distributions: Alpine and Devuan.

Why was the non-existent planet Vulcan so frequently sighted by astronomers in the nineteenth century, and what can contemporary scientists and science students learn from this episode?

There are many kits and plans available for constructing miniature mechanical keyboards. But what do you do if you want a layout the nobody else seems to use? Build it from scratch.

Although connecting a USB keyboard to an Arduino-type microcontroller without addition hardware can be tricky, there are no such problems with many 90s keyboards. This article is about giving new life to old keyboards, by using them as input devices for microcontroller projects.