Texas Instruments TMS320F2837 D Series

Controller Area Network (CAN)
TMS320F2837xD Microcontroller Workshop - Communications 12 - 25
Message Format and Block Diagram
CAN Message Format
 Data is transmitted and received using Message Frames
 8 byte data payload per message
 Standard and Extended identifier formats
 Standard Frame: 11-bit Identifier (CAN v2.0A)
 Extended Frame: 29-bit Identifier (CAN v2.0B)
11-bit
Identifier
R
T
R
S
O
F
I
D
E
r0
DLC
0…8 Bytes Data
CRC
ACK
E
O
F
Arbitration
Field
Control
Field
Data Field
Control
Field
11-bit
Identifier
R
T
R
S
O
F
I
D
E
r0
DLC
0…8 Bytes Data
CRC
ACK
r1
18-bit
Identifier
S
R
R
E
O
F
Arbitration Field
Data Field
The MCU CAN module is a full CAN Controller. It contains a message handler for transmission
and reception management, and frame storage. The specification is CAN 2.0B Active – that is,
the module can send and accept standard (11-bit identifier) and extended frames (29-bit
identifier).
CAN Block Diagram
SN65HVD23x
3.3-V CAN Transceiver
CAN Bus
Message
RAM
32
Message
Objects
CAN Core
Message
RAM
Interface
Message Handler
Register and Message
Object Access (Ifx)
Module Interface
CAN_RX
CAN_TX
Test
Modes
Only
CAN
CPU Bus
(8, 16 or 32-bit)