Using ⅛" stereo plugs, sockets and cables is a convenient way of connection RS232 serial lines between PCs and micro-controllers. Here is a simple little dongle incorporating a USB-to TTL-serial module, a max2323 and an ⅛" stereo jack. TX and RX lines are configurable via jumpers.
A simple but useful co-operative multitasking for AVR microcontrollers.
An ESP8266 WIFI module interfaced to a relay allows for a 1000W/240v swimming-pool filter pump to be remote controlled. It turns on and off automatically depending on how much energy is available from the solar system. Software includes NodeMCU general-purpose telnet server, and Perl client utility.
A quick tutoral guide to setting up a Linux development environment for the ESP8266 WIFI enabled microcontroller. Intended for someone who might have just taken delivery of their first module and is wonder where to start. Covers hardware, firmware, C SDK, and NodeMCU Lua.
Suitable for morse code beacons, repeater idents and the like, this library is implemented as a state machine and hence allowing for other processing to be done whilst the morse is being set.
Eight 1-watt LEDS, a couple of cheap eBay modules, some salvaged hardware, and an ATTINY13 make for some very effective workbench lighting. A speed-controlled fan keeps the electronics and LEDs (and potentially the worker) cool.
This replacement thermostat for an old refrigerator offers LCD display showing temperature in C or F, 0.5C accuracy and allows target temperature to be set percisely. Uses ATmega8 controller and DS18B20 1-wire sensor.
A minimalist DIY programming and development board for the ATtiny2313 AVR microcontroller. Made on a piece of matrix board using point-to-point wiring.