Arbitrary Function generator. Circuit Cellar, No. 396, July 2023. This article desribes the FGEN1, an 8-bit PIC based arbitrary function generator. The FGEN1 covers 0.1 Hz to 20 kHz with 0.1 Hz resolution. New waveforms can easily be defined and added by the user.
Designing a Programmable DC-DC Converter. Nuts & Volts, Vol. 41, 2020 Issue-5. This article reviews the topology of buck, boost, buck/boost and inverting DC-DC converters. The process, and formulas, for designing a digially controlled DC-DC converter by varying the reference voltage is presented and an example design is tested.
Updating a General-Purpose Programming System. Nuts & Volts, Vol. 41, 2020 Issue-4. This article describes the replacement for the LP120 - the LP130 general purpose programmer. The LP130 improves on the LP120 by doubling the clock speed, increasing the memory capacity and adding interface options.
Making a Retro Dumb Terminal. Circuit Cellar, No. 364, November 2020. This article covers VGA theory and the design of the RDT64 terminal. The RDT64 is a classic ASCII dumb terminal capable of displaying text, 64 characters wide by 25 lines high, and limited text-graphics, on a VGA monitor.
THE ROBOEAR. SERVO Magazine, Vol. 16, No. 6, September 2018. This article covers the theory, design and construction of the ROBOEAR, a sound localization system for robots. It uses a three microphone array and cross-correlation signal processing to determine the direction a sound comes from.
Build a Digital Pulse Generator. Circuit Cellar, No. 289, August 2014. This article covers the design of the Digital Pulse Generator kit.
MCU-Based Environmental Data Logger. Circuit Cellar, No. 266, September 2012. This article covers the design and use of a datalogger collecting environmental data such as relative light intensity, temperature, barometric pressure, relative humidity, and more.
Build the Garage Door Closer. Nuts & Volts, Vol. 33, No. 1, January 2012. This article covers the design and construction of a project that will automatically close your garage door when you forget to.
Designing a General-Purpose Programming System - Part 2. Nuts & Volts, Vol. 22, No. 1, January 2001. This article covers the design of the PM-16C and driver software. This LP120 programming-module works with serially programmed PIC microcontrollers.
Designing a General-Purpose Programming System - Part 1. Nuts & Volts, Vol. 21, No. 12, December 2000. This article covers the design of the LP120 hardware and firmware.
Digital Alarm Clock. Nuts & Volts, Vol. 21, No. 5, May 2000. This article describes a complete digital alarm clock based on the MC68HC705J1A.
Build The Joymouse. Electronics Now, Vol. 69, No. 1, January 1998. The workings of analog joysticks and serial mice are explained. A circuit (the Joymouse) to convert an analog joystick into a serial mouse is described.
68705-Based Experimenter's Clock. Electronics Now, Vol. 65, No. 2, February 1994. This article describes the design of a digital clock based on the MC68705P3.
68705 Microcontroller Programmer. Electronics Now, Vol. 65, No. 1, January 1994. This article covers the design of the EP705N.
A Computer-Controlled EPROM Programmer. ComputerCraft, Vol. 2, No. 7, July 1992. This article covers the design of the LP110, the predecessor of the LP120.
MC68705 Single-Chip Microcontrollers. ComputerCraft, Vol. 1, No. 8, November 1991. This article is a tutorial on the MC68705P/R/U family of microcontrollers.
An MC68701 Microcomputer Chip Programmer. Modern Electronics, Vol. 7, No. 5, May 1990. This article covers the design of the EP701.
Microcomputer on a Chip. Modern Electronics, Vol. 7, No. 4, April 1990. This article is a tutorial on the MC68701 microcomputer chip.
A Printer Multiplexer. Modern Electronics, Vol. 5, No. 6, June 1988. This article describes the design of an automatic printer multiplexer, two computers to one printer.