Forum Rule: Always post complete source code & details to reproduce any issue!
Results 1 to 4 of 4

Thread: Teensy 4.0 CAN interfaces

  1. #1

    Teensy 4.0 CAN interfaces

    The main page for the Teesny 4.0 (https://www.pjrc.com/store/teensy40.html) states that is has 2 CAN interfaces. The pinout diagram shows CTX1/CRX1, CTX2/CRX2 and underneath CTX3/CRX3. Are there 2 or 3 CAN interfaces?

    Also, CTX1/CRX1 are shown as being on pins 22/23 and 11/13. Why is this one doubled up?

  2. #2
    Senior Member+ defragster's Avatar
    Join Date
    Feb 2015
    Posts
    11,563
    On that page it shows this correct detail in the 'Technical Specifications' list :: 3 CAN Bus (1 with CAN FD)

    If there is a repeat of info - it may be incorrect or just differentiating the CAN FD from the other "2 CAN interfaces".

    Each pin has a series of capabilities multiplexed. In the case of C[R/T]X1 two of the exposed pin pairs can support CAN1 so the primary and ALT are indicated. With so many other active pins on the 1062 package the capabilities were spread far and wide across pins that could not be routed for use - so few other interfaces offer such 'ALT" capabilities, but it was possible for CAN1

    There is a thread and library by tonton81 for using T_4 CAN.

  3. #3
    Ok thanks for the response. I must have read that list wrong.

  4. #4
    Senior Member
    Join Date
    Dec 2016
    Location
    Montreal, Canada
    Posts
    3,337
    There are 2x CAN2.0 and an extra one which can be either CAN2.0 or CANFD.

    So you can have 3x CAN2.0 for CAN1,CAN2,CAN3
    Or you can have 2x CAN2.0 for CAN1,CAN2 and CANFD for CAN3

    CAN3 also has DMA support for legacy (CAN2.0) FIFO, however, I don't see a difference if we are polling with or without DMA. No interrupts will be generated so....

Posting Permissions

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