{"id":3631,"date":"2021-10-20T09:24:51","date_gmt":"2021-10-20T07:24:51","guid":{"rendered":"https:\/\/www.pschatzmann.ch\/home\/?p=3631"},"modified":"2023-03-22T05:01:35","modified_gmt":"2023-03-22T04:01:35","slug":"a-versatile-but-simple-arduino-streaming-aac-player-with-volume-control","status":"publish","type":"post","link":"https:\/\/www.pschatzmann.ch\/home\/2021\/10\/20\/a-versatile-but-simple-arduino-streaming-aac-player-with-volume-control\/","title":{"rendered":"A Versatile but Simple Arduino Streaming AAC Player with Volume Control"},"content":{"rendered":"

In the last Blogs I presented a File Based Versatile MP3 Player<\/a> and later a A Versatile but Simple Arduino Streaming MP3 Player<\/a> using my Arduino Audio Tools Library<\/a>.<\/p>\n

In this Blog, I will demonstrate how easy it is to convert it into a AAC player. I also show how to control the volume.<\/strong>
\nSo far I was usually using an ESP32 to test the sketch. This time I switch to the cheaper ESP8266!<\/p>\n

The Sketch<\/h3>\n

Here is the Arduino Sketch:<\/p>\n


#include \"AudioTools.h\"\n#include \"AudioCodecs\/CodecAACHelix.h\"\n\nusing namespace audio_tools;  \n\nconst char *urls[] = {\n  \"http:\/\/relay.publicdomainradio.org\/jazz_swing.aac\",\n  \"http:\/\/stream.srg-ssr.ch\/m\/couleur3\/aacp_96\",\n  \"http:\/\/live9.avf.ch:8000\/ipmusicaacplus96\"\n};\nconst char *wifi = \"wifi\";\nconst char *password = \"password\";\n\nURLStream urlStream(wifi, password);\nAudioSourceURL source(urlStream, urls,\"audio\/aac\");\nI2SStream i2s;\nAACDecoderHelix decoder;\nAudioPlayer player(source, i2s, decoder);\nconst int volumePin = A0; \n\nvoid setup() {\n  Serial.begin(115200);\n  AudioLogger::instance().begin(Serial, AudioLogger::Info);\n\n  \/\/ setup output\n  auto cfg = i2s.defaultConfig(TX_MODE);\n  i2s.begin(cfg);\n\n  \/\/ setup player\n  player.begin();\n}\n\nvoid updateVolume() {\n  \/\/ Reading potentiometer value \n  float vol = static_cast<float>(analogRead(volumePin)); \n  \/\/ min in 0 - max is 1.0\n  player.setVolume(vol\/1023.0); \/\/ or change for ESP32: 4095.0);\n}\n\nvoid loop() {\n  updateVolume();\n  player.copy();\n}\n<\/code><\/pre>\n
In order to convert the MP3 code to support AAC<\/strong>, I just needed to replace the urls<\/strong> to provide AAC streams, replace the MP3DecoderHelix with AACDecoderHelix<\/a> and change the mime<\/strong> to “audio\/aac”.<\/p>\n
In order to support the volume control, we read an analog Pin (e.g. GPIO15) and call the player.setVolume()<\/strong> method with a value that is in the rage between 0 and 1.0 and we just need to connect a Potentiometer to this pin.<\/p>\n
Finally I removed the meta data logic, because this is not needed…<\/p>\n
The External DAC<\/h3>\n
For my tests I am using the 24-bit PCM5102 PCM5102A Stereo DAC Digital-to-analog Converter PLL Voice Module pHAT<\/p>\n
\"DAC\"<\/p>\n
I am just using the default pins defined by the framework. However I could change them with the help of the config object. The mute pin can be defined in the constructor of the I2SStream – by not defining anything we use the default which is GPIO23<\/p>\n\n\n\n\n\n\n\n\n\n\n\n\n
DAC<\/th>\nESP32<\/th>\nESP8266<\/th>\n<\/tr>\n<\/thead>\n
VDD<\/td>\n5V<\/td>\n5V<\/td>\n<\/tr>\n
GND<\/td>\nGND<\/td>\nGND<\/td>\n<\/tr>\n
SD<\/td>\nOUT (GPIO22)<\/td>\nGPIO3\/RX0<\/td>\n<\/tr>\n
L\/R<\/td>\nGND<\/td>\nGND<\/td>\n<\/tr>\n
WS<\/td>\nWS (GPIO15)<\/td>\nGPIO2\/TX1<\/td>\n<\/tr>\n
SCK<\/td>\nBCK (GPIO14)<\/td>\nGPIO15<\/td>\n<\/tr>\n
FMT<\/td>\nGND<\/td>\nGND<\/td>\n<\/tr>\n
XSMT<\/td>\n+3V<\/td>\n+3V<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n