Renesas H8S/2158, User Manual

Page: 549 / 929

Section 17 I
2
C Bus Interface (IIC)
Rev. 3.00 Jan 25, 2006 page 495 of 872
REJ09B0286-0300
Bit
Bit
Name Initial
Value
R/W Description
0 ACKB 0 R/W Acknowledge Bit
Stores acknowledge data.
Transmit mode:
[Setting condition]
•
When 1 is received as the acknowledge bit when ACKE = 1
in transmit mode
[Clearing conditions]
•
When 0 is received as the acknowledge bit when ACKE = 1
in transmit mode
•
When 0 is written to the ACKE bit
Receive mode:
0: Returns 0 as acknowledge data after data reception
1: Returns 1 as acknowledge data after data reception
When this bit is read, the value loaded from the bus line
(returned by the receiving device) is read in transmission (when
TRS = 1). In reception (when TRS = 0), the value set by internal
software is read.
When this bit is written, acknowledge data that is returned after
receiving is rewritten regardless of the TRS value. If a flag in
ICSR is written using bit manipulation instructions, the
acknowledge data should be re-set since the acknowledge data
setting is rewritten by the ACKB bit reading value.
Write 0 in the ACKE bit to clear the ACKB flag to 0, before
transmission is ended and a stop condition is issued in master
mode, or before transmission is ended and SDA is released to
issue a stop condition by a master device.
Note:
*
Only 0 can be written, to clear the flag.