Arrays The best way to allocate an Array of data in the AudioTools is by using a Vector. E.g. Vector<int16_t> vector{100000}; is allocating a vector of 100’000 2 byte signed integers. RAM and PSRAM The ESP32 has a few hundred kilobytes of internal RAM, residing on the same die as the rest of the chip components. It can be insufficient for audio, so it has the ability to use up to 4 MB of external Read more
Pure Data (or just “Pd”) is an open source visual programming language for multimedia. Pure Data is developed by Miller Puckette since 1996 and you can find it on his official website along with the official documentation and other related resources. I wanted to have the possibility to run PD patches on microcontrollers. In order to achieve this I am using the hvcc hcompiler that can translate a pd file to c and c++ code. Read more
Quite some time ago, I demonstrated how you can send Audio to your mobile phone using the VBAN protocol. Recently I have added support for receiving data to your microcontroller as well. With this you can use this protocol to build some cool two way communictations applications (e.g. walkie-talkie). Arduino Sketch Here is a sketch that receives the data and just outputs the audio with I2S. Just replace the output class with whatever you want! Read more
In my last post I have complained that my sine wave test sketch was producing just noise. So I am trying now to investigate where the issue is coming from. Using Basic APIs So first, I try an Arduino Sketch which is just using the low level API of my libraries: This configures the codec using the driver API, sets up I2S using the STM32 I2S library and just uses the sine generator from the Read more
In my last post, I was describing that I started to work on adding I2S audio support to the STM32F411 Discovery Board. I finally have my Arduino I2S library that supports the STM32F411 Blackpill and Disovery Board ready. I was completely redesigning the old, mostly generated C library into some C++ classes and I have now a better way to support additional boards. Unfortunately I still don’t have any clean sound on my Discovery Board: Read more
Quite some time ago, I started to look into the STM32F411 Discovery Kit with Arduino. Unfortunatly the audio codec i2c address was not showing up in the port scan. I found out that the chip needs to be activated with setPinMode(PD4, OUTPUT); digitalWrite(PD4, HIGH); One of the reasons why I started my arduino-audio-driver project, was that I wanted to have a clean API for the LQFP100 audio chip that is provided by this board. So Read more
So far I used my arduino-audiokit library together with my AudioTools when I wanted to work with my AudioKit board. This library was a just quick and dirty adaptation of the drivers that were made available by the Espressif ADF framework to Arduino. But it had the following major drawbacks it is complex and difficult to maintain with many layers and quite a lot of source code files in C it is inflexible and you Read more
So far I have always preferred to send audio using the networking functionality of the micro-controllers. This is usually fast and reliable. Many examples can be found in my communications examples folder using different protocols. Using Wires But we can also send audio signals over a physical wire. I prefer to use the Serial protocol because this is well supported across all environments. Just to proof the case I had a simple demo which was Read more
Snapcast is a multiroom client-server audio player, where all clients are time synchronized with the server to play perfectly synced audio. It’s not a standalone player, but an extension that turns your existing audio player into a Sonos-like multiroom solution. This week I have spent some time to work a new client for Arduino that should integrate with my AudioTools and I have a first DRAFT version that started to work. Arduino Sketch Here is Read more
Recently a user was trying to use http to post some audio to be played on a microcontroller with the help of my Audio Tools. This project contains some simple http server implementation, but only for playing audio that is generated by a microcontroller on a webbrowser. However, quite some time ago, I also implemented some extended server functionality in my TinyHttp project and I am using that one now to demonstrate how this can Read more