NEC PD75402A User Manual
Page 108
97
CHAPTER 5. PERIPHERAL HARDWARE FUNCTIONS
(c)
Address
An address is 8-bit data output by the master to slaves connected to the bus line in order to select a particular
slave.
Fig. 5-36 Address
SCK
SB0
Bus Release Signal
Command Signal
Address
1
2
3
4
5
6
7
8
A7
A6
A5
A4
A3
A2
A1
A0
The 8-bit data following the bus release signal and command signal is defined as an address. In a slave this
condition is detected by hardware and a check is performed by hardware to see if the 8-bit data matches the
slave’s own specification number (slave address). If the 8-bit data matches the slave address, that slave is
determined to have been selected and communication is subsequently performed with the master until a
disconnect directive is received from the master.
Fig. 5-37 Slave Selection by Address
Master
Slave 1
Slave 2
Slave 3
Slave 4
Not Selected
Selected
Not Selected
Selected
Sends Address
of Slave