Electronics America 8-Bit Single-Chip Microcontrollers User's Manual

311
CHAPTER 16 SERIAL INTERFACE CHANNEL 0 ( µ PD78054 Subseries)
(c) Address
An address is 8-bit data which the master device outputs to the slave device connected to the bus line
in order to select a particular slave device.
Figure 16-14. Addresses
8-bit data following bus release and command signals is defined as an “address”. In the slave device,
this condition is detected by hardware and whether or not 8-bit data matches the own specification number
(slave address) is checked by hardware. If the 8-bit data matches the slave address, the slave device
has been selected. After that, communication with the master device continues until a release instruction
is received from the master device.
Figure 16-15. Slave Selection with Address
SCK0
A7 A6 A5 A4 A3 A2 A1 A0
12345678
SB0 (SB1)
Address
Command Signal
Bus Release
Signal
Master Slave 1 Not selected
Slave 2 Selected
Slave 3 Not selected
Slave 4 Not selected
Slave 2
address transmission