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8 example of use – Renesas SH7641 User Manual

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Section 16 I

2

C Bus Interface 2 (IIC2)

Rev. 4.00 Sep. 14, 2005 Page 502 of 982

REJ09B0023-0400

16.4.8 Example

of

Use

Flowcharts in respective modes that use the I

2

C bus interface are shown in figures 16.18 to 16.21.

BBSY=0 ?

No

TEND=1 ?

No

Yes

Start

[1]

[2]

[3]

[4]

[5]

[6]

[7]

[8]

[9]

[10]

[11]

[13]

[14]

[15]

Initialize

Set MST and TRS

in ICCR1 to 1

Write 1 to BBSY

and 0 to SCP

Write transmit data

in ICDRT

Write 0 to BBSY

and SCP

Set MST to 1 and TRS

to 0 in ICCR1

Read BBSY in ICCR2

Read TEND in ICSR

Read ACKBR in ICIER

Mater receive mode

Yes

ACKBR=0 ?

Write transmit data in ICDRT

Read TDRE in ICSR

Read TEND in ICSR

Clear TEND in ICSR

Read STOP in ICSR

Clear TDRE in ICSR

End

Write transmit data in ICDRT

Transmit

mode?

No

Yes

TDRE=1 ?

Last byte?

STOP=1 ?

No

No

No

No

No

Yes

Yes

TEND=1 ?

Yes

Yes

Yes

[1]

Test the status of the SCL and SDA lines.

[2]

Set master transmit mode.

[3]

Issue the start candition.

[4]

Set the first byte (slave address + R/

W) of transmit data.

[5]

Wait for 1 byte to be transmitted.

[6]

Test the acknowledge transferred from the specified slave device.

[7]

Set the second and subsequent bytes (except for the final byte) of transmit data.

[8]

Wait for ICDRT empty.

[9]

Set the last byte of transmit data.

[10] Wait for last byte to be transmitted.

[11] Clear the TEND flag.

[12] Clear

the

STOP

flag.

[13] Issue the stop condition.

[14] Wait for the creation of stop condition.

[15] Set slave receive mode. Clear TDRE.

[12]

Clear STOP in ICSR

Figure 16.18 Sample Flowchart for Master Transmit Mode

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