mc9s12hz256v2 Freescale Semiconductor, Inc, mc9s12hz256v2 Datasheet - Page 333

• Manufacturer Part Number: mc9s12hz256v2
• Description: Hcs12 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

Chapter 12
Freescale’s Scalable Controller Area Network (MSCANV2)
12.1
Freescale’s scalable controller area network (MSCAN) definition is based on the MSCAN12 definition,
which is the specific implementation of the MSCAN concept targeted for the M68HC12 microcontroller
family.
The module is a communication controller implementing the CAN 2.0A/B protocol as defined in the
Bosch specification dated September 1991. For users to fully understand the MSCAN specification, it is
recommended that the Bosch specification be read first to familiarize the reader with the terms and
concepts contained within this document.
Though not exclusively intended for automotive applications, CAN protocol is designed to meet the
specific requirements of a vehicle serial data bus: real-time processing, reliable operation in the EMI
environment of a vehicle, cost-effectiveness, and required bandwidth.
MSCAN uses an advanced buffer arrangement resulting in predictable real-time behavior and simplified
application software.
12.1.1
Freescale Semiconductor
Wake-Up Interrupt Req.
Transmit Interrupt Req.
Receive Interrupt Req.
Errors Interrupt Req.
Oscillator Clock
Introduction
Block Diagram
Bus Clock
MSCAN
Figure 12-1. MSCAN Block Diagram
MUX
MC9S12HZ256 Data Sheet, Rev. 2.05
Configuration
CANCLK
Registers
Control
Status
and
Presc.
Tq Clk
Wake-Up
Low Pass Filter
Message
Buffering
Receive/
Transmit
Filtering
Engine
and
RXCAN
TXCAN
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