NEC PD750008 User Manual
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µPD750008 USER'S MANUAL
Figure 5-55. Slave Selection Using an Address
(d) Command and data
The master sends commands to the slave selected by sending an address. The master also transfers
data to or from the slave.
Figure 5-56. Command
Figure 5-57. Data
The 8-bit data following the command signal is defined as a command. The 8-bit data without the
command signal is defined as data. The usage of commands or data can be selected optionally
according to the communication specifications.
(e) Acknowledge signal (ACK)
The acknowledge signal confirms the reception of serial data between the transmitter and the receiver.
Master
Transmits address for
slave 2
Slave 1
Not selected
Slave 2
Selected
Slave 3
Not selected
Slave 4
Not selected
SCK
SB0, SB1
1
2
3
4
5
6
7
8
Command
C7
C6
C5
C4
C3
C2
C1
C0
Command signal
SCK
SB0, SB1
1
2
3
4
5
6
7
8
Data
D7
D6
D5
D4
D3
D2
D1
D0