For quite some time I was looking for an easy way to send some audio to some mobile devices w/o having to write my own mobile application. That’s when I found VBAN. They have some free app (and some payed ones that are reasonably priced) and publish their protocol. So I added the support for VBAN to my AudioTools library and tested the functionality with an ESP32. Here is the basic test sketch: Arduino Sketch Read more
This week I was looking into the FAAD AAC Decoder and tried to make it work on the ESP32. I was struggling quite a bit with the memory requirements and I could only make it work with a stack of 60k and by using PSRAM. So to fulfill the stack requirement we need to run the decoder in a separate freertos task. The Arduino Sketch Here is a working sketch that streams AAC audio from Read more
Today I was receiving my ordered VS1053 MP3 Shield and I was curious about it’s integration with my Arduino Audio Tools Library using the Arduino UNO R4. MP3 Streaming The first thing I tried was the MP3 Streaming sketch. It was working – a kind of. Unfortunately the WIFI is providing the data not fast enough, so it is breaking up badly. What a disappointment: the same sketch is running perfectly on different ESP32 variants Read more
We can try to use a “Bar Chart” to display the result of FFT or the volume, so it is time to have a look at the built in LED Matrix. The basic API to update an LED is as follows: The LED API – Introduction #include “Arduino_LED_Matrix.h” ArduinoLEDMatrix matrix; uint8_t frame[8][12] = {0}; void setup(){ matrix.begin(); frame[7][0] = true; // acivate LED at 0,7 (left lower corner) matrix.renderBitmap(frame, 8, 12); } void loop(){} I have Read more
In my Arduino Audio Tools library I am providing a common API to do FFT against different implementations. I was already testing some of the implementations. On ARM microcontrollers we can use the CMSIS DSP library which usually comes automatically with the Arduino Core. This is not the case for the Arduino UNO R4, but we can install the Arduino CMSIS DSP library with the Arduino library manager. Here is the adapted test sketch that Read more
Today I got very upset by a discussion where a user replaced the original question with a misleading conclusion that mixing an A2DP sink with a sine signal was not possible! Unfortunately he also ignored some helpful comments by some other users. So in order to avoid any confusion I had to delete the whole discussion! Mixing the output from an A2DP sink with a sine signal can be done not only very easily but Read more
I was wondering how to use the timers in the new Arduino UNO R4. Unfortunately I did not find any documentation, so I decided to document my findings here. The UNO R4 has two timer peripherals: the General PWM Timer (GPT) and the Asynchronous General Purpose Timer (AGT). There are only 2 16 bit AGT timers (but one is already used to provide the Arduino millis() and microseconds() methods) and there are 7 GPT timers Read more
In Arduino we can use the analogWrite(pin, value) method to create a PWM signal on the digital pins. The value parameter is used to change the duty cycle but the PWM frequency which is fixed at usually 490 Hz and can not be changed. Here is a simple example sketch that also works with the UNO R4: void setup() { pinMode(D2, OUTPUT); // set 100% analogWrite(D2,255) } void loop() {} Fortunately the Arduino UNO R4 Read more
The easiest way to “record” audio with an Arduino UNO R4 is by using an analog microphone which can be connected to any analog pin. For my test I was using a MCP6022 Microphone Sensor. Arduino Sketch There are no surprises here because we can use the AnalogAudioStream as audio source: #include “AudioTools.h” AnalogAudioStream in; AudioInfo info(8000, 1, 16); CsvOutput<int16_t> out(Serial); // ASCII output stream StreamCopy copier(out, in); // copy i2sStream to CsvOutput // Arduino Read more
This week I received a brand new Arduino UNO R4 in my mail.It uses a Renesas 32 bit microprocessor and has 256 kB Flash and 32 kB RAM. It provides 1 DAC and 6 PWM pins. I got the version which also provides WIFI and a LED matrix. Unfortunately there is no I2S support, but nevertheless I was wondering if I could get some audio from it. I extended my AudioTools Library by implementing a Read more