Part_2_01_First_Design_Tool_Use ?

Can you confirm for me with the TEENSY 4.0 card and the REV.D Audio card that we can superimpose them ?

Yes, this is the normal way to use Teensy 4.0 and Audio Shield rev D. These 2 products are designed so all the pins line up for proper connection when assembled this way.
 
Thank you for this information, "they can be stacked, with the USB connector of the T4.0 pointing the same direction as the audio jack on the Audio Adapter" -> I don't know this information, I just see this link about Audio card : https://forum.pjrc.com/index.php?threads/teensy-4-0-i2s-support.57167/#post-212481
and I do pretty much the same, if I can superimpose on the TEENSY card it would also reduce the connection wires and the noise. Can you confirm for me with the TEENSY 4.0 card and the REV.D Audio card that we can superimpose them ? Thank you for your answer

Yes, and when prototyping, I typically put the Teensy (with pins pointing down) on top, with the Audio Adapter (with sockets pointing up) on the bottom. This makes being able to push (and/or hold, in order to activate the factory reset procedure) the PROGRAM button on the Teensy much easier. Hard soldering them together is not recommended, just in case one or the other experiences an accidental hardware failure (e.g. accidentally touching a Teensy pin with 5VDC . . . The T4.x family I/O pins are not 5VDC tolerant) which may require easy replacement.

Hope that helps . . .

Mark J Culross
KD5RXT
 
Yes, and when prototyping, I typically put the Teensy (with pins pointing down) on top, with the Audio Adapter (with sockets pointing up) on the bottom. This makes being able to push (and/or hold, in order to activate the factory reset procedure) the PROGRAM button on the Teensy much easier. Hard soldering them together is not recommended, just in case one or the other experiences an accidental hardware failure (e.g. accidentally touching a Teensy pin with 5VDC . . . The T4.x family I/O pins are not 5VDC tolerant) which may require easy replacement.

Hope that helps . . .

Mark J Culross
KD5RXT
Hello,
After checking all connections and loading the Guitar example

1727253666755.png

1727253790969.png

I hear a little guitar sound but very drowned out by the noise. I will recheck the software installation. Is it possible that the hardware is faulty ? Either the Teensy card or the Audio card ?
 
Yes, this is the normal way to use Teensy 4.0 and Audio Shield rev D. These 2 products are designed so all the pins line up for proper connection when assembled this way.
Thank you, I had a doubt based on this diagram (the blue and orange) after this link
1727255213328.png

1727255053943.png
 
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I hear a little guitar sound but very drowned out by the noise.

If you hear the guitar sound, perhaps the Teensy and audio shield are working, but there is some problem with the connection to whatever hardware you are using to listen?

Best to use ordinary headphones.

Remember, we can't see what you're connecting (unless you show us or give specific info) and we can't hear the result.

I had a doubt based on this diagram

Indeed that diagram is incorrect.
 
If you hear the guitar sound, perhaps the Teensy and audio shield are working, but there is some problem with the connection to whatever hardware you are using to listen?

Best to use ordinary headphones.

Remember, we can't see what you're connecting (unless you show us or give specific info) and we can't hear the result.



Indeed that diagram is incorrect.
I use this headphones (also with another headphones AKG used on a SAMSUNG S22)
1727257848387.png

which I bought at GOTRONIC at the same time with my TEENSY 4.0 and I have only this information :
1727257984236.png

For the wire I can show you on the TEENSY side (this is the same PIN for Audio card since it's pin to pin and for the PINS correspondence you can see in my #1 post)
1727258546970.png


1727258693958.png


For the son I'll try to record with my phone. The first time when I open Arduino I get this message is this normal ?
1727258930314.png

After a few minutes this message disappears, I will recheck the software installation.
 
Those headphones should work.

Yes, the message about downloading package_teensy_index.json is normal. Arduino IDE automatically downloads this file over and over to check for new versions of the software.

If you are hearing some guitar sound while running the Synth Guitar example, odds are good the connection between Teensy and audio shield is correct. I do not know why it gives you bad sound. Maybe the audio shield is damaged? Or maybe the headphones are defective? Or maybe the plug from the headphones is not mating properly with the socket on the audio shield? Again, I do not know. All I can do is guess (based on the words you hear small guitar sound and large noise... I can not hear this by only these words).

Another possible problem (again, a blind guess) is if the headphone virtual ground (about 1.5V DC) is somehow connected to GND. Notice the words on the bottom side of the audio shield. Normally this is not a problem when only headphones are used, because the headphones do not connect to anything else.
 
Those headphones should work.

Yes, the message about downloading package_teensy_index.json is normal. Arduino IDE automatically downloads this file over and over to check for new versions of the software.

If you are hearing some guitar sound while running the Synth Guitar example, odds are good the connection between Teensy and audio shield is correct. I do not know why it gives you bad sound. Maybe the audio shield is damaged? Or maybe the headphones are defective? Or maybe the plug from the headphones is not mating properly with the socket on the audio shield? Again, I do not know. All I can do is guess (based on the words you hear small guitar sound and large noise... I can not hear this by only these words).

Another possible problem (again, a blind guess) is if the headphone virtual ground (about 1.5V DC) is somehow connected to GND. Notice the words on the bottom side of the audio shield. Normally this is not a problem when only headphones are used, because the headphones do not connect to anything else.
Here the record file (I hope you can hear something). For the headphones both models work I tried on my laptop. "Notice the words on the bottom side of the audio shield". I don't understand what do you mean but I won't be able to look under the audio card anymore since I soldered it at the bottom with the test board like this :

1727262922079.png

for the wiring I will shorten the wires if after that it still does not work, I will ask our supplier for an exchange on the audio card or buy another.
 

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I tried to listen to the "Voix 002.m4a" audio file. I can not hear any guitar sound. No indication the I2S data is causing even slight output.
 
I tried to listen to the "Voix 002.m4a" audio file. I can not hear any guitar sound. No indication the I2S data is causing even slight output.
I can check the signals : LRCLK (44.1 kHz), BCLK (1.41 or 2.82 MHz) and MCLK (11.29 MHz) with my oscilloscope. It's most likely a bad recording because when I put on the headphones I hear a lot of noise but you can make out the sound of the guitar a little.
 
Do you have a voltmeter? While the Guitar program is running, please try measuring DC voltage at several places. In all tests, connect the negative lead to Teensy GND. Connect it close to Teensy.

Measure these as DC voltage: (touch these places with the positive lead on the audio shield, not near Teensy)

Headphone L
Headphone R
LRCLK at audio shield
BCLK at audio shield
MCLK at audio shield
3.3V power at audio shield

1727267406136.png


Edit: on the headphone pins, approx 1.5V confirms the analog circuitry is active. On the 3 clocks, approx 1.65V confirms a 50% duty cycle waveform.
 
Do you have a voltmeter? While the Guitar program is running, please try measuring DC voltage at several places. In all tests, connect the negative lead to Teensy GND. Connect it close to Teensy.

Measure these as DC voltage: (touch these places with the positive lead on the audio shield, not near Teensy)

Headphone L
Headphone R
LRCLK at audio shield
BCLK at audio shield
MCLK at audio shield
3.3V power at audio shield

View attachment 35912
Yes I have a volmeter, I can do it but one question please with the volmeter you can see nothing with the signals :
LRCLK at audio shield
BCLK at audio shield
MCLK at audio shield
Why to do that ?
 
On the 3 clocks, approx 1.65V confirms a 50% duty cycle waveform. If you measure close to 0 volts, the signal is not really connected.
 
You can also use the LED blink example to test any pin. Just edit the pin number and upload. Your voltmeter should see that 1 pin changing at the location on the audio shield, and all the others should not change (check if 2 pins are shorted together). Repeat for every pin.
 
During the connection testing, connect your voltmeter negative lead to GND near Teensy. Touch the positive lead to the solder on top of the pad on audio shield. The idea is to check whether each signal truly does connect all the way from Teensy (transmitting the slow LED blink) to the destination on the audio shield. If you touch the leads at other locations, you may be checking less than the full signal path from Teensy source to audio shield destination.
 
You can also use the LED blink example to test any pin. Just edit the pin number and upload. Your voltmeter should see that 1 pin changing at the location on the audio shield, and all the others should not change (check if 2 pins are shorted together). Repeat for every pin.
I tested with a voltmeter in multimeter position and there is no short circuit. But I can see later the LED blink example
 
Test pin 7 first, since all 3 clocks have 1.65V and I2C previously worked. Pin 7 has the digital audio data from Teensy to audio shield.
 
Test pin 7 first, since all 3 clocks have 1.65V and I2C previously worked. Pin 7 has the digital audio data from Teensy to audio shield.
Can you give me some time because I'm trying to redo the wiring properly by superimposing the 2 cards to reduce the noise. I look at PIN 7 with an oscilloscope probably ?
 
Test pin 7 first, since all 3 clocks have 1.65V and I2C previously worked. Pin 7 has the digital audio data from Teensy to audio shield.
Hi,
Finally, I don't need to do this test because now I can hear the sound of the guitar after taking care of the wiring a little better.

1727445316950.png


1727445366373.png


Thank you
 

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