C Seven Bit Slave Address Register (Isba) - Fujitsu MB90390 Series Hardware Manual

2
21.2.5 I

C Seven Bit Slave Address Register (ISBA)

This register designates the seven bit slave address.
■ I 2
C Seven Bit Slave Address Register
Write access to this register is only possible if the interface is disabled (EN= 0 in ICCR).
R/ W : Readable and writable
- : Undefined
2
■ I
C Seven Bit Slave Address Register Contents
Table 21.2-5 Function of Each Bit of the I
Bit name
bit7 Undefined
SA6 to SA0:
bit6 to bit0 Seven bit slave
address bits
bit 7 6 5 4
Address:
- SA6 SA5 SA4 SA3 SA2 SA1 SA0
0035A6
H
-
R/W R/W R/W
2
C Seven Bit Slave Address Register
This bit always returns "0" during reading.
When address data is received in slave mode, it is compared to the ISBA register if the
seven bit address is enabled (ENSB = 1 in the ISMK register). If a match is detected, an
acknowledge signal is sent to the master device and the AAS bit is set.
All bits of the slave address may be masked using the ISMK register. The received
seven bit slave address is written back to the ISBA register, it is only valid while the
AAS bit in the IBSR register is "1".
The interface does not compare the contents of this register to the incoming data if a ten
bit header or a general call is received.
CHAPTER 21 400 kHz I
3 2 1 0
ISBA
Initial value
0 0 0 0 0 0 0 0
R/W R/W R/W R/W
Function
2
C INTERFACE
B
425