MC68HC05E5 Datasheet, PDF (71/140 Pages) Freescale Semiconductor, Inc – General Release Specification

Freescale Semiconductor, Inc.
Motorola Bus (M Bus) Interface
M-Bus Interface Features
11.3 M-Bus Interface Features
Features of the M-bus interface include:
• Fully Compatible with I²C Bus Standard
• Multimaster Operation
• Software Programmable for 1of 32 Different 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 Identification Interrupt
• Generate/Detect the Start or Stop Signal
• Repeated Start Signal Generation
• Generate/Recognize the Acknowledge Bit
• Bus Busy Detection
11.4 M-Bus System Configuration
The M-bus system uses a serial data line (SDA) and a serial clock line
(SCL) for data transfer. All devices connected to it must have open-drain
or open-collector outputs and the logical AND function is performed on
both lines by two pullup resistors.
11.5 M-Bus Protocol
Normally, a standard communication is composed of four parts: start
signal, slave address transmission, data transfer, and stop signal. These
are described briefly in the following subsections and illustrated in
Figure 11-1.
MC68HC05E5 — Rev. 1.0
General Release Specification
Motorola Bus (M Bus) Interface
For More Information On This Product,
Go to: www.freescale.com