Quite some time ago, I have demonstrated how to build some Guitar Effects with my Arduino Audio Tools. In the last couple of blogs, I showed how to build an interactive web dialog with my TinyHttp library. Finally it is time to put the two approaches together into one single sketch to build some Audio Effects that can be controlled via a html screen. I am using an AudioKit to simplify the hardware setup. The Read more
In my last Blog, I was showing how we can process html forms with the Arduino TinyHttp library. In the examples we were embedding the html into the source code. Sometimes however it is more convenient to store the html as files on a dedicated server: In the following examples we use Github for this. Forwarding In this example we just forward to an external URL. static Url forward_url(“https://pschatzmann.github.io/TinyHttp/app/webservice-example.html”); server.on(“/”,GET, forward_url); This external html page Read more
Today I was playing around with my TinyHttp project: I was investigating how I can drive multiple parameters of a guitar effects sketch by using a web dialog. To provide some information via html is simple. It gets a little bit more complicated if we want to support Html Forms, so I decided to extend the project a bit and provide some examples. A Simple Form Example Here is the link to the source code Read more
I was measuring the speed of the analogWrite() on an STM32 Black Pill on some PWM pins and I was getting a result of around 48697 samples per second. This is enough for one line of hifi data: but I wanted to provide at least 4 channels! This is not good enough: so I generated some new code with 4 PWM output pins using the STMCubeIDE and measured how many duty cycle updates we can Read more
In my Arduino AudioTools I am providing an easy API with different implementations for Fast Fourier Transform (FFT). This is a clever algorithm that can extracts the frequencies from an input signal. So far I never looked at the speed, so I thought it might be interesting to get to know the numbers. Setup I was using an ESP32 and an STM32F411 Black Pill for my tests. The FFT was executed for a length of Read more
The STM32 Cube IDE supports all features of the STM32 microcontrollers, but it is quite difficult to use. The STM32duino is the official Arduino implementation from STM, which is easy to use – but provides only the basic functionality! I was missing I2S in Arduino, so I was wondering, what it takes to convert the code generated from Cube to an Arduino Library for my STM32F411 Black Pill. Unfortunately I did not find any guidance Read more
Quite some time ago I was playing with the idea that it should be quite easy to implement a web server in Arduino that provides the same audio signal to multiple users. All that needs to be done is register new connections and close them when the user closes the browser window. Then we just need to copy the same data to all open connections. That’s how my TinyHttp (Audio) Server got started. This week Read more
Quite some time ago, I tried to use the functionality of the Arduino Audio Tools to download a file from an URL and store it on a SD card, but I was running into some problems. I finally found the time to investigate the issue and I have the functionality finally working now: #include “SD.h” #include “AudioTools.h” const char *ssid = “SSID”; const char *password = “password”; URLStream url(ssid, password); // Music Stream StreamCopy copier; Read more
The AudioKit and some ESP32 Processors have 4MB of SPI RAM that we can use e.g. to store recorded audio. I was playing with the idea to build some looping logic. Therefore I have added an additional DynamicMemoryStream class that can stores the audio data on the heap. With the help of the memory manager we can indicate that data chunks that are above a specified limit are stored in SPI RAM! Arduino Sketch To Read more
I added support for the VS1053 breakout boards to my Arduino Audio Tools project. Finally the recording of sound from the microphone or the aux input is working as well both for the VS1003 and VS1053 devices! Arduino Sketch It is working the same like any other input: #include “AudioTools.h” #include “AudioLibs/VS1053Stream.h” int channels = 1; VS1053Stream in; // Access VS1053/VS1003 as stream CsvStream<int16_t> csvStream(Serial, channels); StreamCopy copier(csvStream, in); // copy in to csvStream // Read more