NEC PD75P402, PD75402A SBI mode serial bus interface mode, Serial Interface Configuration

CHAPTER 5. PERIPHERAL HARDWARE FUNCTIONS

(3) SBI mode (serial bus interface mode)

In the SBI mode, communication is performed with multiple devices by means of two lines: The serial clock (SCK) and the serial data bus (SB0).

This mode conforms to the NEC serial bus format.

In the SBI mode, the sender can output to the serial data bus an address to select the target device for serial communication, a command which gives a directive to the target device, and actual data. The receiver can determine by hardware whether the received data is an address, command or actual data.

Fig. 5-23 Example of SBI System Configuration

		VDD
Master CPU	Serial Clock		Slave CPU
	SCK	SCK	#1	Address 1
	SB0	SB0
	Address
	Command
	Data
			Slave IC
		SCK	#N	Address N
		SB0

Note When the μPD75402A is used as a slave CPU, its address is limited to the range C0H to C7H.

5.5.2Serial Interface Configuration

The serial interface block diagram is shown in Fig. 5-24.

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