Drum Machine Version 2.1 (circa June 2018)

I haven’t worked on my Drum machine for a long time. So in order that I don’t forget what I did I’m writing it down. As I write these posts I realise what a lot of dead-ends I have gone down…

This design was created in early 2018 and was intended to be an expanded version of the first PIC32 design with a some specific goals.

• Create larger device with a less cramped interface than earlier versions
• Use a better/bigger display for both for better visibility and also to display more information
• Add a rotary encoder for additional input (I hacked one in as a test on the old design and it was quite useful)
• Use a “proper” Digital to Analogue Convertor (DAC) in place of Pulse Width Modulation (PWM) plus R/C filter used in the previous design for better quality audio

Single Inline Breakout for 44pin TQFP package PIC32MX170F256D

Here it is in use with straight pins. Sorry about the crappy photo

Schematics for the Chipstomp

Here are the schematics for the Chipstomp.
I’ve tried to keep as much compatibility with the original DP32 circuit but I have removed superfluous elements such as the on-board potentiometer and one of the user leds. I’ve also added an additional tactile button, the OLED and resistor mixed Stereo to Mono input/outputs.
Other than that it’s essentially just a joining of the ChipKit DP32 with the Stomp Shield.
ChipStomp v1 (PDF 90Kb) – Eagle CAD schematic – Zipped (88Kb)

Chipstomp version 1 schematic PNG (2300×1500px, 80Kb)

Introducing the ChipStomp : A Digital effects pedal built with a ChipKit DP32 and a Stompshield

Yet another guitar effects pedal

Here’s something I’ve been working on for a while.  It’s a digital guitar effects processor based on a PIC32MX.  

Drum machine progress : From prototype to version 2

I’ve not posted in a long time so here’s a quick update on the progress of my drum machine. It’s come a fair way from the initial prototype documented in this post back in July 2012.

A sneak look at version 2 with a new 32bit PIC and a new larger LCD

Charlieplexed lighthouse version 2 PCBs have arrived

A long exposure makes it look quite funky

My version two charlieplexed lighthouse circuit PCBs (charliediscs) have arrived back from the Seeedstudio’s fab. I used the same deal as for my last boards, this time it took around 3 weeks in total.  That’s pretty good for 20USD!

My first professionally made PCBs

A stack of PCBs ready to be assembled

I thought I’d have a go at getting my PWM controller PCB made professionally.

Simple PWM control for LED strip

I have been playing around with building a lamp for my desk using a LED strip and constant current driver that I bought from Deal Extreme a while ago combined with a PIC12f683 to provide variable brightness via Pulse Width Modulation (PWM).

The demo using a plain old green LED as the output.

[UPDATE OCT 20 2010] I’ve updated the firmware for this project to include new features. More info and firmware download here.

Lighthouse schematics and files

Update: I’ve revised the schematic for this project and had a proper PCB made, see the new version here.

For anyone who is interested (Hi Richard) here are my project files for the lighthouse project.

The project is written for the PIC12f683 using SourceBoost Technologies BoostC that I use as a tool suite in  Microchip’s MPLAB.  BoostC is fairly ANSI so if you’re using another C then it wouldn’t be hard to convert.  There’s a free version of BoostC too and I think my program will fit within it’s limits.

C source code here (7kb). : Compiled hex binary here (1kb zip).

The schematic and circuit are drawn up using the free version of Cadsoft Eagle. They were created using version 4, but the latest version of Eagle is v5 which I’ve not used yet, however the circuit is fairly simple so I doubt there would be any problems.

High resolution combined print for top and bottom of circuit for toner transfer. (4800x2222px, 163Kb)

Schematic layout of circuit. Note that in the real thing I added a couple of DIP switches in the GP0 & GP1 lines just before the resistors R4 & R5 to isolate the ICSP data and clock lines when programming. (25kb)

I’ve not included the Eagle files themselves as they make use of some random parts that I’ve made in my own library.  But the circuit is not so complex that you couldn’t copy it.  If you really want them then let me know.

If you have any problems drop me a line.