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Hi G Douglas I have experimented with "setAveraging(x) on my T3.6 and found that it makes an x-fold average of each x number of lines of data then puts that average value on all of the lines to which it applies - not useful - it produces a staircase of identical values and an x-fold reduction in...

I am using a Teensy 3.6 to control a Teensy 3.2 which outputs a WAV file periodically. The picture shows the trigger pulse 0.5msec wide sent by the T3.6, and the beginning of the WAV file output from the T3.2. I am surprised that there is a 5msec delay, and a variation of about 1.5msec on that...

I'm still confused. Is Pedvide's ADC library stable with the 3.6? (The thread I see in this forum does not mention the 3.6.) If so, does it require a library call to use it with the 3.6, or has it been included in the basic Teensyduino for the 3.6? I'd prefer not to use an external ADC...

Thanks for the advice (and Shinji). I now have a working preamp using the INA114 with an external Vref. Now for some data.

ADC Vref hardware issue My problem is with the T3.6 hardware. I am trying to install a buffer preamp (MCP602 datasheet fig. 4-11) for the T3.6 ADC using the same 3.3V supply as the T3.6. I had assumed that pin AREF outputs the Vref but it has 3.3V on it at all times, including when using the...

Help! Theremingenieur suggests using this statement:- void analogReference(type), void analogReadRes(bits) and int analogRead(pin) will work in ever case, since they are in the core files, no library needed. Set type=0 for reference=VCC, type=1 for reference=internal (1.2V) to select the...

T3.6 much faster than I thought! Pedvide, thanks so much for your excellent advice. I have rewritten the test program (below) to separately save the data as an array and then print it. I have not yet got the full resolution in the print out but plotting the output: shows that the print...

Failure to get T3.6 continuous synchronized differential outpout Here is my best shot at getting synchronized continuous differential measurements using a T3.6 (180MHz clock). /* MYCDR.ino based upon Example "synchronized measurements" by Pedvide * to optimise continuous differential...

If you upload the latest Teensyduino (version 1.32 beta 1) you will find several example programs for T3.* boards that give the code for pin selection. This works in the latest Arduino version 1.6.13. The Arduino installer removes the previous version automatically. Only the pairs A10, A11...

I'm happy with the speed. Reading ADC.h in detail indicates that my expectations may be based upon misunderstandings. However I have now successfully recorded an AC signal (see image below) using the "synchronised measurements" example, on the T3.6, and with two single ended inputs on pins A9...

Thanks for putting me right Donziboy2. I'm not used to such advanced kit with so many options to handle. The T3.6's performance is plenty adequate for my task. However, reducing the averaging to 4 does not increase acquisition speed according to my 128 line acquisition test; it is still 45ksps...

Thank you very much for the help. I managed to install the new T3.6 code and ran the readAllPins.ino as requested but without changing parameters or the code. All the pins are unconnected except A10, A11 across which I have +0.4V from a battery sourced pot, with a 0.1mF across its output. Here...

ADC Error 0x04 on Teensy 3.6 but not on 3.2 with continuous differential read - why? I am trying to use software adapted from Pedvide example "analogContinuousDifferential Read" on the Teensy 3.6 but with just a single 128line acquisition in "setup" (see picture) and with the "loop" commented...

I received a 3.6 from pjrc sent to England 6th October and received during the second week in October. No delay, no duty requested. The tariff code on the invoice 8542.31.00 seems to be a good one! I don't believe it was a Kickstarter order, just a regular one.

mlu Once again thanks for your help! I have completely rewritten my discontinuous cross-correlation program as you suggested and have now successfully transferred it to the Teensy 3.6 where one set of data now takes 82 millisec to process (clock 180 MHz). The model output below took 8 seconds to...

Importing multiline integer files from PC to Teensy3.1 After several months investigating the Audio board I have realized that it has limited scope; 44.1ksps, inputs transferred to ARM memory only as C++ *.h files, focus on music. I need to be able to upload chirp files sampled at arbitrary...

The WAV to cpp file conversion seems to work OK (see image) and I have made an apparently error-free version of the workshop "Samples" program to play it (it works well with the GONG cpp file). However, the compiler says my cpp file AudioSampleH2K1024w is not "declared" in the loop. I don't...

Paul Sorry, been away. Thanks for your extensive help. Emboldened by the workshop I have relearnt DOS, which I last used in the 1970's. For anybody following this thread and also worried about the brilliant wav2sketch.exe program here's how to do it. 1. put your WAV file with the...

Paul Sure: here is the code I have been trying to get working: // Controller2.pde draft, written on 25/1/2016 based on pjrc examples "sample player" // and "recorder" #include <Audio.h> #include <Wire.h> #include <SPI.h> #include <SD.h> #include <SerialFlash.h> AudioRecordQueue...

I think dBCap may be in the same situation as I: I have spent a day trying to work out what the audio design tool actually gives you. For days I have assumed that, as stated in the notes for "AudioPlayMemory" (or am I misled?), I first have to use the wav2sketch program to convert my files from...

Hi If by #1266 you mean the WavFilePlayer example, I also now have it outputting chirp WAV files generated by Audacity. I have been studying your LED array example but the mention of the 12bit DAC makes me think I should perhaps stick to the queue object. I just want files I can convert to...

Thanks Paul & Frank for your help, Richard

I am using AudioSynthToneSweep to generate a short (.01 to .1 sec) tonesweep and would like to save it to store it directly in memory (not SD card) for subsequent processing. I have been unable to find a means of recording such an internally-generated sound. The wav2sketch program referred to by...

mlu Thank you so much for your help! It could have taken me weeks to find that error. Here is the new (correct) cross-correlation output: I will also rewrite as you suggest. Richard

Thanks. I was incorrectly following Smith's layout but with minor adjustments to the use of the indices should be able to comply with the requirement. According to my VB2012 book VB arrays are the same - starting at zero. So I may have to adjust my VB code too! If so I am still puzzled about...

- That's right, the amplitudes are down too. What puzzles me is that the spike polarities are still visible. I am presently making small changes all through the program to try and find the bug - but so far without success. I would like to make the FFT a function because it is a subroutine in...

This picture shows a comparison between data files cross-correlated on a PC using a VB program and on a Teensy3.1 with audio shield on which a SD card is used to access the same files. The program on the Teensy is a translation from VB to Arduino C and is designed to recover four events sampled...

Thanks. I found necessary parseInt() function for inputting data into the s1[] array in Paul's communication "Re: Reading Values from SDHC card into an Array" of Feb 9th 2014. Now for some results...

Thanks for pointing me to the code in your note, above. I am trying to use it to extract chirp signal spikes embedded in noise as done in sonar and radar by using correlation. I had been using VB on a PC but your ARM code is much faster with the Teensy 3.1. I am trying your software by inputting...

Thank you so much, kpc, for the cross correlation code referred to in your reply to me on the 25th. After a steep learning curve I have finally done the obvious and installed your excellent code, which works! Richard

I've just realized that FFT doesn't give a complex number output, which is required by my correlation algorithm. It looks like your application may not have this problem. I may just have to write my own FFT/correlation code for Teensy 3.1 as a Teensyduino sketch; slow maybe, but I have loads of...

Hi, I was a bit shy about printing the whole thing - it's more or less unchanged from the program provided by pjrc and I still have significant issues to resolve, mostly as to whether I can operate without array storage, at least until, the transmission to the PC. But I was surprised to find...

What a great bit of kit! I have the following solution to my question for anybody out there with a similar need. Having set FFT up for microphone i.e. analog input, adding an int val[1024]; line, and adding a Serial.begin(9600); line in setup so I could upload to my PC, I revised the loop as...

Thanks for the advice, which I will pursue. My algorithm is in fact cross-correlation. It's nearly identical to convolution except for some data flipping. The system uses a shaped "chirp" output and correlates this chirp with returning signals to extract the times at which a facsimile of the...

I have used VB FFT deconvolution code from S W Smith's marvellous "Digital Signal Processing" book to process 1024 sample chunks of geophysical data and would like to transfer this function to the Teensy 3.1. Each sample chunk is obtained at intervals of between 0.25 and 5 seconds. The...