Datasheet

Section 17 I
2
C Bus Interface (IIC)
Rev. 3.00 Sep. 28, 2009 Page 521 of 910
REJ09B0350-0300
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 ICDRE or ICDRF flag is set, the IRTR flag may or may not be set. The IRTR 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.
Tables 17.5 and 17.6 show the relationship between the flags and the transfer states.
Table 17.5 Flags and Transfer States (Master Mode)
MST TRS BBSY ESTP STOP IRTR AASX AL AAS ADZ ACKB ICDRF ICDRE State
1 1 0 0 0 0 0↓ 0 0↓ 0↓ 0 — 0 Idle state (flag
clearing
required)
1 1 1↑ 0 0 1↑ 0 0 0 0 0 — 1↑ Start condition
detected
1 — 1 0 0 — 0 0 0 0 — — — Wait state
1 1 1 0 0 — 0 0 0 0 1↑ — — Transmission
end (ACKE=1
and ACKB=1)
1 1 1 0 0 1↑ 0 0 0 0 0 — 1↑ Transmission
end with
ICDRE=0
1 1 1 0 0 — 0 0 0 0 0 — 0↓ ICDR write with
the above state
1 1 1 0 0 — 0 0 0 0 0 — 1 Transmission
end with
ICDRE=1
1 1 1 0 0 — 0 0 0 0 0 — 0↓ ICDR write with
the above state
or after start
condition
detected
1 1 1 0 0 1↑ 0 0 0 0 0 — 1↑ Automatic data
transfer from
ICDRT to ICDRS
with the above
state