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wrong demo!

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ladyada 2017-11-21 23:36:11 -05:00
parent 6ffe240e13
commit 99fc8760c7
2 changed files with 47 additions and 53 deletions
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53
Adafruit_UDA1334A/SimpleTone/SimpleTone.ino
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/*
This example generates a square wave based tone at a specified frequency
and sample rate. Then outputs the data using the I2S interface to a
MAX08357 I2S Amp Breakout board.
Circuit:
* Arduino/Genuino Zero, MKRZero or MKR1000 board
* MAX08357:
* GND connected GND
* VIN connected 5V
* LRC connected to pin 0 (Zero) or pin 3 (MKR1000, MKRZero)
* BCLK connected to pin 1 (Zero) or pin 2 (MKR1000, MKRZero)
* DIN connected to pin 9 (Zero) or pin A6 (MKR1000, MKRZero)
created 17 November 2016
by Sandeep Mistry
*/
#include <I2S.h>
const int frequency = 440; // frequency of square wave in Hz
const int amplitude = 500; // amplitude of square wave
const int sampleRate = 8000; // sample rate in Hz
const int halfWavelength = (sampleRate / frequency); // half wavelength of square wave
short sample = amplitude; // current sample value
int count = 0;
void setup() {
Serial.begin(9600);
Serial.println("I2S simple tone");
// start I2S at the sample rate with 16-bits per sample
if (!I2S.begin(I2S_PHILIPS_MODE, sampleRate, 16)) {
Serial.println("Failed to initialize I2S!");
while (1); // do nothing
}
}
void loop() {
if (count % halfWavelength == 0) {
// invert the sample every half wavelength count multiple to generate square wave
sample = -1 * sample;
}
// write the same sample twice, once for left and once for the right channel
I2S.write(sample);
I2S.write(sample);
// increment the counter for the next sample
count++;
}

47
Adafruit_UDA1334A/SineTone/SineTone.ino Normal file
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/*
This example generates a sine wave based tone at a specified frequency
and sample rate. Then outputs the data using the I2S interface.
Public Domain
*/
#include <I2S.h>
#define FREQUENCY 440 // frequency of sine wave in Hz
#define AMPLITUDE 10000 // amplitude of sine wave
#define SAMPLERATE 44100 // sample rate in Hz
int16_t sinetable[SAMPLERATE / FREQUENCY];
uint32_t sample = 0;
#define PI 3.14159265
void setup() {
Serial.begin(115200);
Serial.println("I2S sine wave tone");
// start I2S at the sample rate with 16-bits per sample
if (!I2S.begin(I2S_PHILIPS_MODE, SAMPLERATE, 16)) {
Serial.println("Failed to initialize I2S!");
while (1); // do nothing
}
// fill in sine wave table
for (uint16_t s=0; s < (SAMPLERATE / FREQUENCY); s++) {
sinetable[s] = sin(2.0 * PI * s / (SAMPLERATE/FREQUENCY)) * AMPLITUDE;
}
}
void loop() {
if (sample == (SAMPLERATE / FREQUENCY)) {
sample = 0;
}
// write the same sample twice, once for left and once for the right channel
I2S.write((int16_t) sinetable[sample]); // We'll just have same tone on both!
I2S.write((int16_t) sinetable[sample]);
// increment the counter for the next sample in the sine wave table
sample++;
}