Audio Example AudioShield - TeensyUser/doc GitHub Wiki
This is the tonesweep program set up to use the PJRC audio shield. Revisions A-C of the audio shield are used with the Teensy 3.1, 3.2, 3.5, or 3.6. Revision D of the audio shield is used with the Teensy 4.0.
/*
Demo of the audio sweep function.
The user specifies the amplitude,
start and end frequencies (which can sweep up or down)
and the length of time of the sweep.
Pins: Teensy 4.0 Teensy 3.x
LRCLK: Pin 20/A6 Pin 23/A9
BCLK: Pin 21/A7 Pin 9
DIN: Pin 7 Pin 22/A8
SCL (I2C): Pin 19/A5 Pin 19/A5
SDA (I2C): Pin 18/A4 Pin 18/A4
Ground: Ground Ground
3.3v: 3.3v 3.3v
VIN: 5v 5v */
#include <Audio.h>
#include <Wire.h>
#include <SPI.h>
#include <SD.h>
#include <SerialFlash.h>
// GUItool: begin automatically generated code (edited by meissner afterwards).
AudioSynthToneSweep tonesweep; //xy=99,198
AudioControlSGTL5000 sgtl5000;
AudioMixer4 mixer2; //xy=280,253
AudioMixer4 mixer1; //xy=280,175
AudioOutputI2S shield; //xy=452,189
AudioConnection patchCord1 (tonesweep, 0, mixer1, 0);
AudioConnection patchCord2 (tonesweep, 0, mixer2, 0);
AudioConnection patchCord3 (mixer2, 0, shield, 1);
AudioConnection patchCord4 (mixer1, 0, shield, 0);
// GUItool: end automatically generated code
const float t_ampx = 0.8;
const int t_lox = 10;
const int t_hix = 22000;
const float t_timex = 10; // Length of time for the sweep in seconds
// Do a sweep in both directions, enabling or disabling the left/right speakers
void do_sweep (int i)
{
int do_left = (i & 1) != 0;
int do_right = (i & 2) != 0;
float gain = (do_left && do_right) ? 0.5f : 1.0f;
Serial.printf ("Sweep up, left = %c, right = %c\n",
(do_left) ? 'Y' : 'N',
(do_right) ? 'Y' : 'N');
mixer1.gain (0, do_left ? gain : 0.0f);
mixer2.gain (0, do_right ? gain : 0.0f);
if (!tonesweep.play (t_ampx, t_lox, t_hix, t_timex)) {
Serial.println ("ToneSweep - play failed");
while (1)
;
}
// wait for the sweep to end
while (tonesweep.isPlaying ())
;
// and now reverse the sweep
Serial.printf ("Sweep down, left = %c, right = %c\n",
(do_left) ? 'Y' : 'N',
(do_right) ? 'Y' : 'N');
if (!tonesweep.play (t_ampx, t_hix, t_lox, t_timex)) {
Serial.println ("ToneSweep - play failed");
while (1)
;
}
// wait for the sweep to end
while (tonesweep.isPlaying ())
;
Serial.println ("Sweep done");
}
void setup(void)
{
// Wait for at least 3 seconds for the USB serial connection
Serial.begin (9600);
while (!Serial && millis () < 3000)
;
AudioMemory (8);
sgtl5000.enable ();
sgtl5000.volume (0.5f);
Serial.println ("setup done");
for (int i = 1; i <= 3; i++)
do_sweep (i);
Serial.println ("Done");
}
void loop (void)
{
}