ESP32 and PWM – Part 2

In this second part of my look into the ESP32 and PWM I've updated the code to expand to several channels to make a sort of (fixed) simple signal generator. Part 1 - All the theory and research around PWM and the ESP32. Part 2 - Generating different waveforms on multiple channels. Part 3 - Introducing analog … Continue reading ESP32 and PWM – Part 2 →

PICO2/AFPOC

February saw another momentous step in the ambitious John Cage Organ Art Project at Halberstadt when the playing chord changed for the first time in two years. The resultant chord will now continue to play for another two years before the next change. The project is a performance of John Cage's ORGAN2/ASLSP, generally known by … Continue reading PICO2/AFPOC →

ESP32 and PWM

I'm continuing reinventing wheels with my ESP32. In ESP32 and Mozzi I was using the built-in DAC for audio output. In this post I'm taking a detailed look at how to use PWM for audio output instead. Part 1 - All the theory and research around PWM and the ESP32. Part 2 - Generating different waveforms on … Continue reading ESP32 and PWM →

ESP32 and Mozzi

I've been meaning to do something with the ESP32 for some time. I have some general ESP32-C3 devices, and a range of XIAO ESP32 (S2 and C3) devices too, but what I was particularly interested in was the original ESP32 as it includes two 8-bit DACs. This is my first set of experiments using a … Continue reading ESP32 and Mozzi →

Diagnosing and attempting to fix a Yamaha DX100 – Part 2

At the end of part 1, I've established that the basics all seem ok (PCB, interconnections, power) and that basic digital logic stuff is happening. I rounded off my write-up with the following ideas for what to investigate next: Get some proper triggering from the chip enables to check for valid data signals. Check out … Continue reading Diagnosing and attempting to fix a Yamaha DX100 – Part 2 →

CD Rack Format Zynthian – Part 2

I've recently updated my "CD Rack" box to a horizontal black box, still shaped for my "CD Rack" format modules. But as it is black, and I've a black TX816, I've rebuilt my CD Rack format Zynthian with a black, PCB front panel too. Original Design Notes: CD Rack Format Zynthian. Warning! I strongly recommend using … Continue reading CD Rack Format Zynthian – Part 2 →

Arduino Direct Digital (Additive) Synthesis

This is actually a collection of previous projects with the code tidied up a little and combined to show a single sketch that can be configured for either PWM, an R2R ladder or the MCP4725 I2C DAC. There isn't really anything here that hasn't been talked about before somewhere, but hopefully this can act as … Continue reading Arduino Direct Digital (Additive) Synthesis →

Raspberry Pi Pico Synth_Dexed? – Part 6

One last thing I definitely wanted for my PicoDexed was the option for PWM output. This post is by way of a short coda detailing how to do PWM on a Raspberry Pi Pico. Part 1: Building Synth_Dexed for the Pico. Part 2: Assessing the performance and analysis of the Pico audio library. Part 3: … Continue reading Raspberry Pi Pico Synth_Dexed? – Part 6 →

Raspberry Pi Pico Synth_Dexed? – Part 5

Ok, ignore my last comment about Part 4 being my last post on this topic. I thought I ought to pull together all the hardware notes on how to build one as I haven't really written that down anywhere. So this shows the connections required between the Pico, I2S DAC and MIDI IN. Part 1: … Continue reading Raspberry Pi Pico Synth_Dexed? – Part 5 →

Raspberry Pi Pico Synth_Dexed? – Part 4

I was going to leave things at Part 3 blog-wise, and just get on with filling in the gaps in code now, but I've come back to add a few more notes. But this is likely to be the final part now. Recall so far, I have: Part 1 where I work out how to … Continue reading Raspberry Pi Pico Synth_Dexed? – Part 4 →