PaulStoffregen
Well-known member
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.
Part_2_01_First_Design_Tool_Use ?
- Thread starter DOY38
- Start date
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.
kd5rxt-mark
Well-known member
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
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 ?
Thank you, I had a doubt based on this diagram (the blue and orange) after this link
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PaulStoffregen
Well-known member
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)
which I bought at GOTRONIC at the same time with my TEENSY 4.0 and I have only this information :
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)
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 ?
After a few minutes this message disappears, I will recheck the software installation.
PaulStoffregen
Well-known member
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.
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 :
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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PaulStoffregen
Well-known member
I ordered this card (REV.D) :
Module audio pour Teensy 4.0 et 4.1
Présentation et fonctionnalités : Shield basé sur un SGTL5000 ajoutant une sortie audio à une carte Teensy 4.0 ou 4.1 (non incluse).
www.gotronic.fr
PaulStoffregen
Well-known member
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.
PaulStoffregen
Well-known member
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
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.
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
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.
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 ?
PaulStoffregen
Well-known member
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.
PaulStoffregen
Well-known member
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.
PaulStoffregen
Well-known member
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.
I tested with a voltmeter in multimeter position and there is no short circuit. But I can see later the LED blink example
PaulStoffregen
Well-known member
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 ?
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.
Thank you