
MC9S12XDP512 Data Sheet, Rev. 2.15
Freescale Semiconductor
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Chapter 10
Freescale’s Scalable Controller Area Network
(S12MSCANV3)
10.1
Introduction
Freescale’s scalable controller area network (S12MSCANV3) denition is based on the MSCAN12
denition, which is the specic 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 dened in the
Bosch specication dated September 1991. For users to fully understand the MSCAN specication, it is
recommended that the Bosch specication be read rst 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
specic 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 simplied
application software.
10.1.1
Glossary
ACK: Acknowledge of CAN message
CAN: Controller Area Network
CRC: Cyclic Redundancy Code
EOF: End of Frame
FIFO: First-In-First-Out Memory
IFS: Inter-Frame Sequence
SOF: Start of Frame
CPU bus: CPU related read/write data bus
CAN bus: CAN protocol related serial bus
oscillator clock: Direct clock from external oscillator
bus clock: CPU bus realated clock
CAN clock: CAN protocol related clock