38 CAN - Controller Area Network

This family of devices contain a Controller Area Network (CAN) module. CAN is a serial interface which is useful for communicating with other peripherals or microcontroller devices. This interface, or protocol, was designed to allow communications within noisy environments.

The CAN module is a communication controller, implementing the CAN protocol as defined in the BOSCH specification. This module supports CAN 1.2, CAN 2.0A, CAN 2.0B Passive, and CAN 2.0B Active versions of the protocol. The module implementation is a full CAN system; however, the CAN specification is not covered within this data sheet. Refer to the BOSCH CAN specification for further details.

Features of the CAN module include:


  • Bit rate up to 1 Mbps
  • CAN Controller modes:
    • Configuration mode
    • CAN 2.0B mode
    • Disable mode
    • Listen-Only mode
    • Restricted Operation mode
    • Internal and External Loopback modes
  • Conforms to ISO11898-1

Message FIFOs

  • 3 FIFOs configurable as transmit or receive FIFOs
  • One Transmit Queue (TXQ)
  • Transmit Event FIFO (TEF) with 32-bit timestamp

Message Transmission

  • Message transmission prioritization:
    • Based on priority bit field and/or
    • Message with lowest ID gets transmitted first using the TXQ
  • Programmable automatic retransmission attempts: unlimited, three attempts or disabled

Message Reception

  • 12 flexible filter and mask objects
  • Each object can be configured to filter either:
    • Standard ID and first 18 data bits or
    • Extended ID
  • 32-Bit timestamp