Datasheet

Section 15 I
2
C Bus Interface (IIC)
Rev. 3.00 Sep. 28, 2009 Page 362 of 710
REJ09B0384-0300
Figure 15.7 shows the sample flowchart for the operations in master transmit mode.
Start
Initialize IIC
Set MST = 1 and
TRS = 1 in ICCR
Set BBSY =1 and
SCP = 0 in ICCR
Write transmit data in ICDR
Clear IRIC in ICCR
No
No
Yes
Yes
Yes
Yes
No
No
[1] Initialization
[3] Select master transmit mode.
[4] Start condition issuance
[6] Set transmit data for the first byte
(slave address + R/W).
(After writing to ICDR, clear IRIC
continuously.)
[9] Set transmit data for the second and
subsequent bytes.
(After writing to ICDR, clear IRIC
immediately.)
[2] Test the status of the SCL and SDA lines.
[7] Wait for 1 byte to be transmitted.
[10] Wait for 1 byte to be transmitted.
[11] Determine end of transfer
[12] Stop condition issuance
[8] Test the acknowledge bit
transferred from the slave device.
[5] Wait for a start condition generation
Read IRIC in ICCR
Read ACKB in ICSR
IRIC = 1?
ACKB = 0?
Transmit mode?
Write transmit data in ICDR
Clear IRIC in ICCR
Read IRIC in ICCR
Read ACKB in ICSR
Clear IRIC in ICCR
End of transmission?
(ACKB = 1?)
Set BBSY = 0 and
SCP = 0 in ICCR
End
Read BBSY in ICCR
BBSY = 0?
Yes
No
Read IRIC in ICCR
IRIC = 1?
Yes
No
Yes
No
IRIC = 1?
Master receive mode
Figure 15.7 Sample Flowchart for Operations in Master Transmit Mode