PaulS
Senior Member

Hi Michael, reading your statement: do you see a potential revival of this particular chip architecture? Or perhaps even an update of the DSP24 chip? Do you have a specific area of the AI market in mind? Paul

Interesting. Did you design the system yourself? This DSP-24 chip apparently was designed around the year 2000. The company DSP Architectures doesn't seem to be alive anymore. Just curious why you used this particular...

You are powering the thermistor-resistor divider from the 5V. You better power it from the 3V3 pin : the Teensy will not survive a voltage higher than 3V3 on its input pins, the ADC range of the Teensy is 0V - 3V3....

I'm not sure I understand your question correctly, but these few lines of code sends the @ character as if a USB keyboard is connected: void loop() { Keyboard.println("@"); delay(1000); } Paul

Perhaps this thread can get you started? Paul

Another possibility is to use one or more 74AHCT1G08's (a single 2-input AND gate). This part is used on PJRC's Prop Shield as a level-shifter. Paul

From this page: Since a HIGH output of Teensy is 3V3 max, an HC part will not suffice. Paul

USB enumeration by the PC host is using the data that is sent and received over the D+ and D- lines. Those lines are referenced from the USB GND line (not from VUSB). The host will supply VUSB but it won't be used by...

Thanks Frank, for that usable info. I never dove into this matter but this enlightens a lot. Found some more pictures and tutorials: What I showed in message #5 is merely a rude piezo-based knock-sensor... ...

In order to advice you which library to use, it's useful to know what display you are intending to use. Paul

Yes, you can but you have to power the ADXL1002 from the Teensy 3V pin (or an external powersupply <= 3V3). Depending on your application you may want add a low-pass filter as described in the datasheet. Paul

You may want to have a look at this code that runs on this board. Paul

Perhaps some silicone placemat? Paul

The sequencer output goes to a synthesizer, correct? Could it be that the synthesizer does not support the Channel Mode Message: All Notes Off? (your partial code looks OK to me) Paul

According to the datasheet, the TLV75733 has an output accuracy of -+1%. Using a Fluke 111 multimeter, I just measured two Teensy 4.0's: 3.299V & 3.320V. So within spec. Is your meter OK? Paul

You're welcome. In the thread you are referring to, it was Paul Stoffregen, founder of PJRC, who replied several times - not me :) With respect to the Schottky diodes: I felt the 1N5817 to be a safer choice do its...

Can confirm the observation by mkoch. Here is the scope image: And here is what the logic analyzer shows: For completeness, here is the code that shows the behaviour:

That's weird. Would you mind posting your complete code (don't know what "value" is) that shows this behaviour so that I can hook up the logic analyzer and check the data? Thanks, Paul

Just to show you: this afternoon I built a simple drum pad using a piezo transducer, a 110mm PVC cap and an EPDM rubber sheet on top. A Teensy LC samples the transducer signal and sends a MIDI note to Ableton...

Found two 8-channel high-side source drivers in DIP18 package that look to be available for $1-2: TBD62783APG and UDN2981A. Paul

Except for the current limiting resistors for the LEDs, the schematic is OK. What you are looking for is a high-side switch, useful info here. High-side switches are also known as "load switches". With a high-side...

I'm not sure that I understand you fully. The ULQ2003 is a low-side switch: it switches an individual output to the common GND at pin 8. The COM pin #9 is for the common-cathode suppression...

Perhaps the 74HC14 is a bit too slow for this application? I see a transition time of ~50ns. Although you can operate a 74HC14 at 3V3, it's significant slower than running a 5V. But more importantly, I'm not seeing...

It's difficult to predict how good or bad foam, rubber and metal discs will work together. Since that's all mechanical interaction, it's best to experiment with different materials and find out what works best for you....

Allright, perhaps your Teensy survived. Can you test whether the pins are actually working by settings the individual pin outputs HIGH & LOW and measure the pins? . Can you also draw a little schematic how you wired...

When you power the ADXL1002 with 3V3 from Teensy pin "3V" and connect the ADXL1002 output to an ADC pin, you can start testing and coding. For regular sampling you can use the 'analogRead' command. For more advanced...

Just checking: you accidentally shorted C17 and C29 by a solder blob and then tried to remove it? Did you power the Teensy while that short was present? Did you try the "Blink" program? Tried your code and it...

Cutting the traces does not have the same effect as removing the resistors. It's for setting the CAN chip in a certain mode. So you have to remove that resistor carefully from the PCB. Paul

Three 120Ω resistors in parallel make ~40.5Ω. So like Tonton81 suggested, remove the 120Ω resistor from your CAN device. Paul

Piezo sensors may output higher voltage pulses than a Teensy can handle. Checkout this thread for more info. Google this for even more info. Paul

These 2 threads may help you further: https://forum.pjrc.com/threads/60139-Reading-BLDC-Hall-Sensors-using-interrupts and https://forum.pjrc.com/threads/72121-Three-Phase-Encoder. Paul

UsbTreeView is useful tool to see what USB devices are connected to your PC. Paul

When fully connected to the vehicle you should see 60Ω. Your measurement of 120Ω is correct for a not-connected OBD plug. Paul

I'm pretty sure all DSP effects are disabled by default - but Paul Stoffregen can tell for sure. Just curious: where did you read about "Freeverb", "reverb" and "damping"? Could not find these words in the SGTL5000...

Vgnd is NOT the ground for the Line in/Line out signals - it's the virtual ground for headphone output. It should definitely NOT be connected to the regular GND througholes. See the also the schematic. If connected,...

I used a 1N5822 which I had laying around. Paul

The Teensy 4.1 isn't affected if it is powered from both the USB cable and VIN input at the same time. The problem occurs at the USB port of your PC or at your external power supply. Whichever supply has the...

Which Arduino IDE version are you referring to? 2.1.0 or 1.8.19? Did you follow the exact instructions on this page? Where is the "Blink Both" folder located? I don't recall seeing this folder ever. Paul

Did you connect it according to this pinout? (no need to connect VCC) Paul

Did you try swapping the CAN-L and CAN-H lines? (been there, done that...) Paul

And the Motu M2 spectrum with the same -24dB signal: Paul

And yes, the Scarlett front-end was apparently overloaded - when I changed the output amplitude of the PCM5102 board to sine1.amplitude(0.0625); // -24dB the spectrum analyzer shows this for the Scarlett: For...

Thanks Mark, it's probably a combination of what you suggested. An hour ago I hooked up a third USB audio interface (an ESI U24XL) and that one shows this on TrueRTA: Now -90dB down... Still not sure what I...

@veroelectric: this page may help you further. Paul

When we are talking about a Teensy 4.x, than, according to this page, "The recommended maximum output current is 4mA." If the motor of the analog gauge is indeed a stepper motor, you won't be able to drive that...

Just ran the code from my message #6 above, using the exact same hardware, but this time compiled with ArduinoIDE 2.0.4 & Teensyduino 1.58.0: Program runs fine and shows the same on the CAN Analyzer. Please...