Cooper Dalrymple
a426fbf51d
* Added buffer read to `AudioBufferManager` and `I2S`. Example and documentation included. * Update type of words to unsigned in example. * Improve buffered loopback example. * Remove const from read buffer.
40 lines
866 B
Arduino
40 lines
866 B
Arduino
/*
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I2S bi-directional input and output buffered loopback example
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Released to the Public Domain by Cooper Dalrymple
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*/
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#include <I2S.h>
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I2S i2s(INPUT_PULLUP);
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#define SIZE 256
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int16_t buffer[SIZE];
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void setup() {
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Serial.begin(115200);
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i2s.setDOUT(0);
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i2s.setDIN(1);
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i2s.setBCLK(2); // Note: LRCLK = BCLK + 1
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i2s.setBitsPerSample(16);
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i2s.setFrequency(22050);
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i2s.setBuffers(6, SIZE * sizeof(int16_t) / sizeof(uint32_t));
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i2s.begin();
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size_t count, index;
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while (1) {
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count = i2s.read((uint8_t *)&buffer, SIZE * sizeof(int16_t)) * sizeof(uint32_t) / sizeof(int16_t);
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index = 0;
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while (index < count) {
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// Reduce volume by half
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buffer[index++] >>= 1; // right
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buffer[index++] >>= 1; // left
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}
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i2s.write((const uint8_t *)&buffer, count * sizeof(int16_t));
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}
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}
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void loop() {
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/* Nothing here */
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}
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