Forum Rule: Always post complete source code & details to reproduce any issue!
Results 1 to 6 of 6

Thread: Teensy 4.1 compatibility pin with teensy 3.6

  1. #1

    Teensy 4.1 compatibility pin with teensy 3.6

    Hi,
    I wanted to know if teensy 4.1 was compatible with teensy 3.6 at the pin level.
    Can I replace the teensy 3.6 with a teensy 4.1 while continuing to use my programs
    without changing the hardware pins for the spinnaker for example my tft lcd, serial ...

    Thanks for your help.

  2. #2
    Senior Member+ defragster's Avatar
    Join Date
    Feb 2015
    Posts
    12,398
    Knowing the specific pins and usage will tell ...

    Generally all pin function is preserved - but pin locations/numbers for some minimal number of functions shifted. For the major functions and busses they are generally preserved - but in doing that where internal chip function mapping was different - other pins had to be called on in different locations - and some prior 'Alt' second pin for support are not available on the T_4.x.

    Looking at the Teensy Cards and details on PJRC.com for the two will generally indicate the changes when confirming the pins used and needed.

  3. #3
    Thank you for your answer and your
    clarification.

  4. #4
    Senior Member+ defragster's Avatar
    Join Date
    Feb 2015
    Posts
    12,398
    you are welcome.

    See also this post : pjrc.com/threads/63244-Teensy-4-1-multiple-devices

    For a PDF with alternate view info of the T_4.1 pins

  5. #5
    Senior Member+ KurtE's Avatar
    Join Date
    Jan 2014
    Posts
    7,664
    As @defragster has mentioned, Paul tried to maintain has much common pin functionality that he could do between the boards. But each of these processors map different functionality to different pins. So often times you have to prioritize which common functionality has a higher priority.

    That is: On most all of the boards, Pins (0,1) are for Serial1, likewise pins 10-13 are the default SPI pins, and 18-19 are the default Wire pins.

    Example of trade off: On T3.6 Serial 2 is on pins 9 and 10, but those pins that could for example be chosen for pin 10 for the Hardraw CS, did not have one that was also a Serial port TX pin...

    But they do have in common Hardware Serial port on pins 7-8 although on 3.6 this is Serial3 and on T4 Serial2...

    So as @defragster mentioned, it is easier to look at the cards that ship with the board. Or I look at some excel documents that show all of the functionality of each pin.

  6. #6
    Senior Member+ MichaelMeissner's Avatar
    Join Date
    Nov 2012
    Location
    Ayer Massachussetts
    Posts
    3,849
    I put the following entry in the unofficial wiki to document many of the inter-Teensy compatibility issues:


    Basically as KurtE says, the pins that are common:
    • The first serial port (0, 1);
    • The pins for the first SPI bus (11, 12, and 13);
    • The pins for the first I2C bus.


    In addition,
    • The main ground, 3.3v, vin, and vusb pins are all in the same place;
    • Pin 13 is connected to an on-board LED;
    • Analog inputs can be done on pins 14-23. These pins have the alternate names of A0..A9;
    • Pins 3, 4, 6, 22, and 23 are the common PWM (pulse-width modulation) pins across all Teensys.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •