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  1. R

    Raw USB Serial

    It looks like there is a notification defined in the CDC documentation for SERIAL_STATE which is intended to communicate UART bits, though it doesn't list CTS among the mapped UART signals. Sending a notification to the host appears to require setting up a notification specific interrupt...
  2. R

    Raw USB Serial

    I built a Teensy USB MIDI project years ago for interfacing a morse code key to a PC, it works great, but some people just can't figure out MIDI. It turns out that there is another way to interface a morse code key to a PC over a serial port. It toggles CTS and DSR in one direction and RTS in...
  3. R

    What applications truly need both Teensy 3.5 / 3.6 built in DACs?

    They could be used to generate IQ for an SDR transmitter, but most SDR applications have gone for the extra 4 bits with the AudioAdapter.
  4. R

    Possible new shields

    I have been a long time fan of the Dontronics SimmStick system. You mount your microprocessor and run all the pins out on a parallel bus to a series of SIMM sockets. Then you build extension boards with fingers and notches that mate to the SIMM sockets. Each extension board pulls only the...
  5. R

    indicator lights for buttons

    Ah, normally the note goes on when the switch is pressed and goes off when the switch is released, like a piano key. And that's what people have explained how to do and that's what you've coded. But that's not what you want, you want the switch press to toggle note on/off and the LED to track...
  6. R

    Teensy 4.0 First Beta Test

    You could use one of https://www.adafruit.com/product/2045, as a frequency generator. It's a $7.95 breakout for an i2c programmable oscillator, with adafruit library.
  7. R

    Translate code from Teensy LC to Teensy 3.2?

    I didn't see any code that would be a problem. You should compile it and try it out. -- rec --
  8. R

    Not understanding touchRead

    Touching a piece of metal directly connected to a touch sensing pin works fine, until you discharge a bolt of static electricity into the pin, which is why capacitive touch sensors aren't made that way. -- rec --
  9. R

    AudioProcessorUsage()???

    Thank you, that works fine. -- rec --
  10. R

    AudioProcessorUsage()???

    Are there any known problems with AudioProcessorUsage()? This program: /* -*- mode: c++; tab-width: 8 -*- */ #include <Audio.h> #include <Wire.h> #include <SPI.h> #include <SD.h> #include <SerialFlash.h> // Create the Audio components. AudioInputUSB usb2; AudioAmplifier...
  11. R

    Two seperate programs in a Teensy 3.6

    Oh, some good points in that code. If you wanted to compile for two different USB device interfaces, you couldn't use the namespaces like I did, because you need to compile and link with the USB interface specified. And if your code is doing global initializations then they'll happen in both...
  12. R

    Two seperate programs in a Teensy 3.6

    So as it is, you have rtty.ino and cw.ino, each with bunches of functions and data defined, and numerous potential conflicts of naming. I think you can wrap your existing programs each inside its own c++ namespace and then write a third program which chooses which of the namespaces to...
  13. R

    Teensy 3.2 TSI Interrupt

    A frustrating puzzle. The following code works. It doesn't use the periodic measurement mode, but it accomplishes the same effect in the same number of instructions. -- rec -- void tsi0_isr() { # toggle the led GPIOC_PTOR |= (1 << 5); # reset the end-of-scan flag, trigger next scan...
  14. R

    Arduino Events

    You can call it Dispatch.
  15. R

    Continuous Touch Sensing

    The original Teensy 3's implemented a background continuous touch sensing mode in hardware, but the Teensy LC and Teensy 3.6 don't. I suspect that it can be done with a DMA program: transfer pad number to touch sense register, start measurement, wait for measurement to complete, transfer...
  16. R

    Teensy 3.1 Audio Library - Envelope limited to 1000 ms?

    When this came up in my audio processing class I think the answer was that the corners of the envelope are always smoothed so there are no corners. Discontinuities in the rate of change make clicks. So convert the trapezoidal envelope into a smooth curve of samples at instantiation, and simply...
  17. R

    Can a USB keyboard be used to control a project running on Teensy 3.1?

    It's a technical quibble, but it may save you some grief in the future, but what you see are many examples of Teensy as a USB _device_. The computer which uses the Teensy as a mouse or keyboard is a USB _host_. All computers are devices, of course, and most of them host various things, but...
  18. R

    Type C USB

    Yeah, I was checking the prices of USB-C connectors at Digikey, the one's in stock are $4.69 a piece at the moment, and there are 3000 in stock. In comparison a micro-B connector is $0.76 a piece and there are 100,000 in stock. (But I also found a 2 meter USB-A-male to USB-B-male cable for...
  19. R

    Type C USB

    I've been musing over the Type C USB connector on my Chromebook. I watched a 40 minute video at Cypress this morning, http://www.cypress.com/?rID=111101, and I've downloaded the USB Type C documents http://www.usb.org/developers/usbtypec/, but I'm still at the earliest stages of exploring this...
  20. R

    USB MIDI and Audio

    An audio sink device has to give the host rate feedback on a separate endpoint so the host can adjust the number of samples per buffer up or down. I believe it sends one fixed point fraction of feedback for each usb buffer received and it's reporting how far ahead or behind the ideal number of...
  21. R

    USB MIDI and Audio

    http://forum.pjrc.com/threads/23942-Using-Serial-and-MIDI-USB-types-at-the-same-time?p=33405&viewfull=1#post33405 discusses this in terms of a Serial+MIDI composite device. The hidden complication is that the basic MIDI device is already a MIDI+HID composite where the HID channel implements...
  22. R

    Audio For Teensy3 - What Features Would You Want?

    I am a bit late to the party, but let me say this will work for my applications. It should be fine for most audio applications just as it is. And thanks for figuring out that the I2S/PLL only works for 44.1 kHz. It might have been very painful designing to use the PLL at other sample rates...
  23. R

    teensy 3 external power

    I think you want to give 5V to Vin or Vusb. Consulting the schematic, http://www.pjrc.com/teensy/schematic.html, the USB pin 5 connects to the Vusb pin, goes through a 500 mA fuse, goes through the cuttable jumper between Vusb and Vin, then drops through two parallel diodes to the VREGIN...
  24. R

    Teensy 3.0 FreqCounter

    Hi all -- I was looking at implementing a frequency counter on the Teensy 3.0 using the general scheme of the Arduino FreqCounter library. So we look for a timer that can count incoming pulses, gate it on for a period, and see how many counts we get during the period. So, the Flex Timer...
  25. R

    PITimer: PIT (Periodic Interrupt Timer) library for Teensy 3.0

    It's getting rounded even when you give it an integer number of milliseconds or microseconds. What you get is integer numbers of whatever clocks the processor has to count, with whatever jitter or drift there might be to that number. If the interval you want is a whole number of clock ticks...
  26. R

    PITimer: PIT (Periodic Interrupt Timer) library for Teensy 3.0

    I'd say implement both interfaces: timer.begin(cb0, 1); // milliseconds timer.beginMicroseconds(cb0, 1000); // microseconds This matches the convention on delay() and extends obviously to Nanoseconds in the future. Allowing both integer and floating point intervals should be matched with...
  27. R

    Is library "Firmata" working on the Teensy 3?

    My problems were with a freshly upgraded Ubuntu 13.04, and with the Ubuntu 12.10 that it replaced. No fix required for me, I'll just use my phone as a hotspot. I updated all sources from the firmata.org repos, then added the Boards.h fix for Teensy 3.0. The source for...
  28. R

    Is library "Firmata" working on the Teensy 3?

    I had fits getting firmata working today, using Ubuntu and the Teensy 3.0. Fixing the Boards.h definitions was the easy part, none of the firmata_test variants would work. I believe that the problem may be that the modem-manager has been upgraded in recent versions to ignore all the careful...
  29. R

    Teensy 3.0 Specs

    One missing document is the actual data sheet for the K20 family: http://cache.freescale.com/files/32bit/doc/data_sheet/K20P64M50SF0.pdf This sets out the power and frequency limits for this sub-family. For instance, the ADC clock, ADCK, for the Teensy 3.0 must be between 1 MHz and 18 MHz for...
  30. R

    Rotary Encoder?

    The problem is that the library needs to be rewritten for the Teensy 3.0, the list of boards supported is on the web page you linked. The FlexTimer module (FTM) is described in chapter 35 of the processor reference manual. It has hardware support for quadrature decoding.
  31. R

    Help with ADC speed

    You can find all the magic register names and numbers in the K20 Sub-Family Reference Manual, http://cache.freescale.com/files/32bit/doc/ref_manual/K20P48M50SF0RM.pdf It's a 1200 page pdf so don't get impatient downloading it or trying to read it. I've turbocharged my ADC conversion by...
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