4509 Datasheet, PDF (45/142 Pages) Renesas Technology Corp – SINGLE-CHIP 4-BIT CMOS MICROCOMPUTER

4509 Group
(5) How to use serial interface
Figure 38 shows the serial interface connection example. Serial in-
terface interrupt is not used in this example. In the actual wiring, pull
up the wiring between each pin with a resistor. Figure 38 shows the
data transfer timing and Table 16 shows the data transfer sequence.
Master (clock control)
Slave (external clock)
D3
SCK
SOUT
SIN
(Bit 3)
00
(Bit 0)
11
Serial interface
control register J1
Serial interface port
SCK,SOUT,SIN
Instruction clock/8 selected
as synchronous clock
SRDY signal
D3
SCK
SIN
SOUT
(Bit 3)
11
(Bit 0)
11
Serial interface
control register J1
Serial interface port
SCK,SOUT,SIN
External clock selected
as synchronous clock
(Bit 3)
0✕
(Bit 0)
✕✕
Interrupt control
register V2
Serial interface
interrupt enable bit
(SNZSI instruction
valid)
Fig. 38 Serial interface connection example
(Bit 3)
0✕
(Bit 0)
✕✕
Interrupt control
register V2
Serial interface
interrupt enable bit
(SNZSI instruction
valid)
✕: Set an arbitrary value.
Rev.1.02 2006.12.22 page 45 of 140
REJ03B0147-0102