Hi,
I have a very naive question but I can't find a answer so far... so .. looking for some help from the experts
I have a Teensy3.1 with the Audio Shield.
I setup the board as from the examples, my purpose is to capture audio at 44.1 from LineIN.
I don't need audio out.
I noticed weird gliches on the audio in, so I connected BOTH the L+R to GND with a wire and I simply run one printf in the main loop
I was expecting a flat value, but I see something weird:
from time (in a somewhat regular pattern...) I get a zero value (sort of)
...
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
0.0001220
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
0.0000915
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
0.0001220
-1.0000000
is this correct?
since the input is grounded I was not expecting these glitches.
maybe I did setup the shield in a wrong way?
Note: I did this test because when capturing audio I cannot get a "clean" signal,
I have always some spike at regular intervals on the input stream, seems to be every 256 samples or so...
:-(
I have no peripherals connected,
just the usb cable to my laptop.
I have a very naive question but I can't find a answer so far... so .. looking for some help from the experts
I have a Teensy3.1 with the Audio Shield.
I setup the board as from the examples, my purpose is to capture audio at 44.1 from LineIN.
I don't need audio out.
Code:
// Enable the audio shield and set the input/output volume.
audioShield.enable();
audioShield.adcHighPassFilterDisable();
audioShield.inputSelect(AUDIO_INPUT_LINEIN);
audioShield.lineInLevel(0,1); //2.2Vpp
audioShield.autoVolumeDisable();
//don't need audio output, mute level
audioShield.volume(0);
I noticed weird gliches on the audio in, so I connected BOTH the L+R to GND with a wire and I simply run one printf in the main loop
Code:
HWSERIAL.println(peak1.read() ,DEC);
I was expecting a flat value, but I see something weird:
from time (in a somewhat regular pattern...) I get a zero value (sort of)
...
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
0.0001220
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
0.0000915
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
-1.0000000
0.0001220
-1.0000000
is this correct?
since the input is grounded I was not expecting these glitches.
maybe I did setup the shield in a wrong way?
Note: I did this test because when capturing audio I cannot get a "clean" signal,
I have always some spike at regular intervals on the input stream, seems to be every 256 samples or so...
:-(
I have no peripherals connected,
just the usb cable to my laptop.