UPD784938 Datasheet, PDF (461/733 Pages) NEC – 16-Bit Single-Chip Microcontrollers

CHAPTER 19 3-WIRE SERIAL I/O MODE
19.4 3-Wire Serial I/O Mode
The 3-wire serial I/O mode is used to communicate with devices that incorporate a conventional clocked serial interface.
Basically, communication is performed using three lines: the serial clock (SCK0), serial data output (SO0), and serial
data input (SI0). Generally, a handshake line is necessary for checking the communication status.
Figure 19-3. Example of 3-Wire Serial I/O System Configuration
Master CPU
Slave CPU
SCK0
SCK
SO0
SI
µ PD784938
SI0
SO
Note
Port (interrupt)
Port
Port
Interrupt (port)
Note Handshake lines
Preliminary User’s Manual U13987EJ1V0UM00
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