Freescale Semiconductor M68HC08 series, Руководство по проектированию

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Introduction
Designer Reference Manual DRM047 — Rev 0
16 Introduction MOTOROLA
advantage of LIN-bus over other bus protocols (like CAN) is low system
cost. This is because the LIN-bus protocol is based on standard and
cost-effective serial SCI (UART compatible) hardware modules. These
are implemented on most Motorola MCU/DSP devices. An enhanced
SCI is called ESCI.
Other serial bus protocols like CAN require a specialized hardware
module. They can have higher communication speed than LIN-bus. But
the overall system cost of such systems is much higher. Therefore many
of car electronics systems should be based on LIN-bus protocol.
This reference design shows that the LIN-bus protocol speed is fully
sufficient for a headlamp leveller with a stepper motor actuators. The
advantage versus other bus protocols, such as CAN-bus, is low system
cost.
1.5 Definitions and Acronyms
The definitions and acronyms used in this reference design are listed
below.
(signal) Acceptor the device which receives and responses to
a bus signal
AFS Advanced Front Lighting System
Cairone see Power Die
ESCI Enhanced Serial Communication Interface
DSP Digital Signal Processor
ECT Enhanced Capture Timer
HID Lamp High Intensity Density headlamp
LIN Leveller the system described in this reference
design. It consists of the LIN master and
LIN stepper controllers
LIN-bus a local interface network standard for serial
asynchronous communication (see
Section 9. References , 2 )
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Freescale Semiconductor, Inc.
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