Datasheet
MOTOROLA MCF5206e USER’S MANUAL 13-1
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SECTION 13
M-BUS MODULE
13.1 OVERVIEW
Motorola bus (M-Bus) is a two-wire, bidirectional serial bus that provides a simple, efficient
method of data exchange between devices. It is compatible with the widely used I
2
C bus
standard
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. This two-wire bus minimizes the interconnection between devices.
This bus is suitable for applications requiring occasional communications over a short
distance between many devices. The flexible M-Bus allows additional devices to be
connected to the bus for expansion and system development.
The interface operates up to 100 kbps with maximum bus loading and timing.
The M-Bus system is a true multimaster bus including collision detection and arbitration that
prevents data corruption if two or more masters attempt to control the bus simultaneously.
This feature allows for complex applications with multiprocessor control. It can also be used
for rapid testing and alignment of end products via external connections to an assembly line
computer.
13.2 INTERFACE FEATURES
The M-Bus module has the following key features:
• Compatibility with I
2
C Bus standard
• Multimaster operation
• Software-programmable for one of 64 different serial clock frequencies
• Software-selectable acknowledge bit
• Interrupt-driven byte-by-byte data transfer
• Arbitration-lost interrupt with automatic mode switching from master to slave
• Calling address identification interrupt
• Start and stop signal generation/detection
• Repeated START signal generation
• Acknowledge bit generation/detection
• Bus-busy detection
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I
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C-Bus is a proprietary Phillips interface bus.
Fr
eescale S
emiconduct
or
, I
Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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