Datasheet

Section 15 I
2
C Bus Interface2 (IIC2) (Option)
Rev.6.00 Mar. 18, 2009 Page 640 of 980
REJ09B0050-0600
Bit Bit Name Initial Value R/W Description
4 NACKF 0 R/W No acknowledge detection flag
[Setting condition]
When no acknowledge is detected from the receive device
in transmission while the ACKE bit in ICIER is 1
[Clearing condition]
When 0 is written in NACKF after reading NACKF = 1
Note: When NACKF = 1 is detected, NACKF must be
cleared to 0. Subsequent transmission in not made
until NACKF is cleared to 0.
3 STOP 0 R/W Stop condition detection flag
[Setting conditions]
• In master mode, when a stop condition is detected after
frame transfer
• In slave mode, when a stop condition is detected after
the general call address or the first byte slave address,
next to detection of start condition, accords with the
address set in SAR
[Clearing condition]
When 0 is written in STOP after reading STOP = 1
2 AL 0 R/W Arbitration Lost Flag
This flag indicates that arbitration was lost in master mode.
When two or more master devices attempt to seize the bus
at nearly the same time, if the I
2
C bus interface detects data
differing from the data it sent, it sets AL to 1 to indicate that
the bus has been taken by another master.
[Setting conditions]
• If the internal SDA and SDA pin disagree at the rise of
SCL in master transmit mode
• When the SDA pin outputs high in master mode while a
start condition is detected
[Clearing condition]
When 0 is written in AL/OVE after reading AL/OVE=1