I am working on a DAC design using the PCM1794 with I2S support but it does not seem to work correctly.
The design for the chip is based on the typical application in the datasheet using TL074 chips as op-amps in the I/V stage.
How are you supposed to connect I2S to this chip if it looks like this on an oscilloscope? Measured directly from teensy. The frequencies measured are correct, according to the audio shield page. To me this does not really look like standard I2S, and these voltages seem really high particularly mclk. Is it even possible to use the teensy with the PCM1794, or have I missed something really obvious?
The source for the test program:
The design for the chip is based on the typical application in the datasheet using TL074 chips as op-amps in the I/V stage.
How are you supposed to connect I2S to this chip if it looks like this on an oscilloscope? Measured directly from teensy. The frequencies measured are correct, according to the audio shield page. To me this does not really look like standard I2S, and these voltages seem really high particularly mclk. Is it even possible to use the teensy with the PCM1794, or have I missed something really obvious?
The source for the test program:
Code:
#include <Arduino.h>
#include <Audio.h>
#include <Wire.h>
#include <SPI.h>
#include <SD.h>
#include <SerialFlash.h>
// GUItool: begin automatically generated code
AudioSynthWaveformSine sine1; //xy=268,404
AudioOutputI2S i2s1; //xy=568,403
AudioConnection patchCord1(sine1, 0, i2s1, 0);
// GUItool: end automatically generated code
void setup() {
AudioMemory(2000);
sine1.frequency(2000);
sine1.amplitude(1);
}
void loop() {
}