The MIDI Replay stomp box is a powerful configuration and recording device for keyboard players, based on the wonderful MIDI protocol: the standard musical language of over 30 years.
This article explores the design challenges of this real-time system and covers topics such as task scheduling, buffers, parallel computing, dynamic memory management, response time analysis and menu system design.
When my wife and I moved into our current home a few years back, it didn’t have a doorbell. We live on a quiet cul-de-sac, so it really wasn’t a problem as we had few callers. After a while, I installed a wireless doorbell that lasted about three years. Recently, after writing the series of articles on “A Digital Analog — When a PIC Can Replace a 555,” I decided to make one using a PIC.
This final article in our series will examine those circuits from the “555 Timer IC Circuits” by Forrest Mims which were not covered in any of the preceding four articles.
I’ve been searching for a way to give our band’s performances the kind of visual elements that can only otherwise be achieved by true lighting artists. As a musician, inventor, and laser enthusiast, I decided to draw on all my hobbies and have created a light machine that has unique responses to each tone, frequency, and beat.
Driving LEDs using the lowest possible pin-count is a common challenge for folks creating projects with microcontrollers. Complementary LED drive, also known as “Charlieplexing”, allows a large number of LEDs to be controlled with a relatively small number of I/O pins. This fun digital LED clock project is a hands-on example of how Charlieplexing can be used to stretch your “pin budget”!
Debugging microcontroller designs can be difficult due to resource limitations that block or curtail access to real time information internally and externally. In this article, I’ll demonstrate both a multiplexed bus protocol analyzer and the 1-Wire Manchester decoder. Combining these logic analyzer decoders with an embedded software Manchester encoder forms a great tool to enhance your debugging and diagnostic skills.
This fourth installment will examine the more complex circuits from the book, “555 Timer IC Circuits” by Forrest Mims. Some will use the PIC replacement from Part 1, while others will develop specific programs using a PIC to emulate a particular implementation of a 555.
Over the years, I have accumulated a bunch of chips from before the era of true PCs when computers with names like Altair, KIM-1, and Cosmac ELF were popular. I’ve been looking for a way to use them in new projects, so I designed a system around a 40-pin PIC16F887. I figured this would put some of my historic chips to work and be a great learning tool for understanding how a microcomputer works.
This six-digit, beautifully designed timepiece showcases cold war era components — Numitrons instead of Nixie tubes — along with modern LEDs and a Microchip PIC to create not only a useful clock but a great conversation piece as well.
Most electronic devices today have a single button you push to turn them on and off. Think of your cell phone, laptop, and even your TV. There is no toggle to flip, no knob to turn back and forth, nor slide switch to move. So, how do you get one of these power buttons into your project so your latest gadget can sit next to your other devices without the embarrassment of a toggle or slide switch?
