Freescale Semiconductor MCF51QE128RM manual Initialization/Application Information, Module Use

13.7Initialization/Application Information

Module Initialization (Slave)

1.Write: IICC2

—to enable or disable general call

—to select 10-bit or 7-bit addressing mode

2.Write: IICA

—to set the slave address

3.Write: IICC1

—to enable IIC and interrupts

4.Initialize RAM variables (IICEN = 1 and IICIE = 1) for transmit data

5.Initialize RAM variables used to achieve the routine shown in Figure 13-12

Module Initialization (Master)

1.Write: IICF

—to set the IIC baud rate (example provided in this chapter)

2.Write: IICC1

—to enable IIC and interrupts

3.Initialize RAM variables (IICEN = 1 and IICIE = 1) for transmit data

4.Initialize RAM variables used to achieve the routine shown in Figure 13-12

5.Write: IICC1

—to enable TX

6.Write: IICC1

—to enable MST (master mode)

7.Write: IICD

—with the address of the target slave. (The lsb of this byte determines whether the communication is master receive or transmit.)

Module Use

The routine shown in Figure 13-12can handle both master and slave IIC operations. For slave operation, an incoming IIC message that contains the proper address begins IIC communication. For master operation, communication must be initiated by writing to the IICD register.

Register Model

IICA

AD[7:1]

0

IICF

When addressed as a slave (in slave mode), the module responds to this address

MULT ICR

Baud rate = BUSCLK / (2 x MULT x (SCL DIVIDER))

IICC1

IICEN IICIE MST TX TXAK RSTA 0 0

Module configuration

IICS

TCF IAAS BUSY ARBL 0 SRW IICIF RXAK

Module status flags

IICD

DATA

Data register; Write to transmit IIC data read to read IIC data

IICC2 GCAEN ADEXT 0 0 0 AD10 AD9 AD8

Address configuration

Figure 13-11. IIC Module Quick Start

MCF51QE128 MCU Series Reference Manual, Rev. 3

Freescale Semiconductor 2-277