
MC68HC05BD3
MOTOROLA
7-1
M-BUS SERIAL INTERFACE
7
M-BUS SERIAL INTERFACE
M-Bus (Motorola Bus) is a two-wire, bidirectional serial bus which provides a simple, efcient way
for data exchange between devices. It is fully compatible with the I2C bus standard. This two-wire
bus minimizes the interconnection between devices and eliminates the need for address
decoders; resulting in less PCB traces and economic hardware structure. This bus is suitable for
applications requiring communications in a short distance among a number of devices. The
maximum data rate is 100Kbit/s. The maximum communication length and number of devices that
can be connected are limited by a maximum bus capacitance of 400pF.
The M-Bus system is a true multi-master bus, including arbitration to prevent data collision if two
or more masters intend to control the bus simultaneously. It may be used for rapid testing and
alignment of end products via external connections to an assembly-line computer.
7.1
M-Bus Interface Features
Compatible with I2C bus standard
Multi-master operation
32 software programmable serial clock frequencies
Software selectable acknowledge bit
Interrupt driven byte-by-byte data transfer
Arbitration lost driven interrupt with automatic mode switching from master to slave
Calling address identication interrupt
Generate/detect the start, stop and acknowledge signals
Repeated START signal generation
Bus busy detection
TPG
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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