Datasheet

Section 16 I
2
C Bus Interface [Option]
Rev. 4.00 Sep 27, 2006 page 510 of 1130
REJ09B0327-0400
When, with the I
2
C bus format selected, IRIC is set to 1 and an interrupt is generated, other flags
must be checked in order to identify the source that set IRIC to 1. Although each source has a
corresponding flag, caution is needed at the end of a transfer.
When the TDRE or RDRF internal flag is set, the readable IRTR flag may or may not be set. The
IRTR flag (the DTC start request flag) is not set at the end of a data transfer up to detection of a
retransmission start condition or stop condition after a slave address (SVA) or general call address
match in I
2
C bus format slave mode.
Even when the IRIC flag and IRTR flag are set, the TDRE or RDRF internal flag may not be set.
The IRIC and IRTR flags are not cleared at the end of the specified number of transfers in
continuous transfer using the DTC. The TDRE or RDRF flag is cleared, however, since the
specified number of ICDR reads or writes have been completed.
Table 16.3 shows the relationship between the flags and the transfer states.
Table 16.3 Flags and Transfer States
MST TRS BBSY ESTP STOP IRTR AASX AL AAS ADZ ACKB State
1/0 1/0 0 0 0 0 0 0 0 0 0 Idle state (flag clearing
required)
1 1 0 0 0 0 0 0 0 0 0 Start condition issuance
1 1 1 0 0 1 0 0 0 0 0 Start condition established
1 1/0 1 0 0 0 0 0 0 0 0/1 Master mode wait
1 1/0 1 0 0 1 0 0 0 0 0/1 Master mode transmit/
receive end
0 0 1 0 0 0 1/0 1 1/0 1/0 0 Arbitration lost
0 0 1 0 0 0 0 0 1 0 0 SAR match by first frame in
slave mode
0 0 1 0 0 0 0 0 1 1 0 General call address match
0010001 0000 SARX match
0 1/0 1 0 0 0 0 0 0 0 0/1 Slave mode
transmit/receive end
(except after SARX match)
0
0
1/0
1
1
1
0
0
0
0
1
0
1
1
0
0
0
0
0
0
0
1
Slave mode
transmit/receive end (after
SARX match)
0 1/0 0 1/0 1/0 0 0 0 0 0 0/1 Stop condition detected