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CAN Controller Block Diagram and System Integration
Figure 25-1: CAN Controller Block Diagram
CAN Controller
CAN Core
Message
RAM
Message
RAM
Interface
Message
Handler
Register
Block
Slave Interface
Host Processor
(MPU Subsystem)
DMA
Controller
System
Manager
L4 Peripheral Bus
Interrupt Request
DMA Peripheral
Request Interface
CAN Bus Interface
CAN_TXD
CAN_RXD
ECC Control
Signals
The CAN controller consists of the following modules and interfaces:
• CAN core
• Connects to the CAN bus interface
• Handles all ISO 11898-1 protocol functions
• Message handler
• State machine that controls the data transfer between the message RAM and CAN core.
• Handles acceptance filtering and the interrupt generation
• Message RAM
• Storage for up to 128 messages objects
• Single bit error correction and double bit error detection
• Message RAM interface
• Two separate interfaces,
IF1
and
IF2
• Register block
• Control and status registers (CSR) for module setup and indirect message object access.
• All host processor accesses to the message RAM are relayed through the message RAM interface.
• Level 4 (L4) slave interface for CSR accesses
CAN Controller Introduction
Altera Corporation
cv_54025
CAN Controller Block Diagram and System Integration
25-2
2013.12.30