Overview
1418
SPNU563A – March 2018
Copyright © 2018, Texas Instruments Incorporated
Controller Area Network (DCAN) Module
27.1 Overview
The Controller Area Network is a high-integrity, serial, multi-master communication protocol for distributed
real-time applications. This CAN module is implemented according to ISO 11898-1 and is suitable for
industrial, automotive and general embedded communications.
27.1.1 Features
The DCAN module provides the following features:
Protocol
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Supports CAN protocol version 2.0 part A, B
Speed
•
Bit rates up to 1 MBit/s
MailBox
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Configurable Message objects
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Individual identifier masks for each message object
•
Programmable FIFO mode for message objects
High Speed MailBox Access
•
DMA access to Message RAM.
Power
•
Global power down and wakeup support
•
Local power down and wakeup support
Debug
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Suspend mode for debug support
•
Programmable loop-back modes for self-test operation
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Direct access to Message RAM in test mode
•
Supports Two interrupt lines - Level 0 and Level 1
Others
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Automatic Message RAM initialization
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Automatic bus on after Bus-Off state by a programmable 32-bit timer
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CAN Rx / Tx pins configurable as general purpose IO pins
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Software module reset
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Message RAM with SECDED mechanism
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Dual clock source to reduce jitter
27.1.2 Functional Description
The CAN protocol is an ISO standard (ISO 11898) for serial data communication. This protocol uses Non-
Return To Zero (NRZ) with bit-stuffing. And the communication is carried over a two-wire balanced
signaling scheme.
The DCAN data communication happens through the CAN_TX and CAN_RX pins. An additional
transceiver hardware is required for the connection to the physical layer (CAN bus) CAN_High and
CAN_Low.
The DCAN register set can be accessed directly by the CPU. These registers are used to control and
configure the CAN module and the Message RAM.
Individual CAN message objects should be configured for communication over a CAN network. The
message objects and identifier masks are stored in the Message RAM.