HD64F2638F20J Datasheet, PDF (620/1512 Pages) Renesas Technology Corp – Renesas 16-Bit Single-Chip Microcomputer H8S Family/H8S/2600 Series

Section 15 I²C Bus Interface [Option]
(Only for the H8S/2638, H8S/2639, and H8S/2630)
H8S/2639, H8S/2638, H8S/2636,
H8S/2630, H8S/2635 Group
Bit 3—Arbitration Lost (AL): This flag indicates that arbitration was lost in master mode. The
I²C bus interface monitors the bus. When two or more master devices attempt to seize the bus at
nearly the same time, if the I²C 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.
AL is cleared by reading AL after it has been set to 1, then writing 0 in AL. In addition, AL is
reset automatically by write access to ICDR in transmit mode, or read access to ICDR in receive
mode.
Bit 3
AL
0
1
Description
Bus arbitration won
[Clearing conditions]
(Initial value)
• When ICDR data is written (transmit mode) or read (receive mode)
• When 0 is written in AL after reading AL = 1
Arbitration lost
[Setting conditions]
• If the internal SDA and SDA pin disagree at the rise of SCL in master transmit
mode
• If the internal SCL line is high at the fall of SCL in master transmit mode
Bit 2—Slave Address Recognition Flag (AAS): In I²C bus format slave receive mode, this flag is
set to 1 if the first frame following a start condition matches bits SVA6 to SVA0 in SAR, or if the
general call address (H'00) is detected.
AAS is cleared by reading AAS after it has been set to 1, then writing 0 in AAS. In addition, AAS
is reset automatically by write access to ICDR in transmit mode, or read access to ICDR in receive
mode.
Page 570 of 1458
REJ09B0103-0800 Rev. 8.00
May 28, 2010