UPD17073 NEC, UPD17073 Datasheet - Page 112

• Manufacturer Part Number: UPD17073
• Description: 4-BIT SINGLE-CHIP MICROCONTROLLER WITH HARDWARE FOR DIGITAL TUNING SYSTEM
• Manufacturer: NEC

14. SERIAL INTERFACE
14.1 General
latter uses SCK, SI, and SO0 pins.
112
Remarks 1. SIOCK1 and 0 (bits 0 and 1 of serial I/O clock select register. Refer to Figure 14-2) set a shift clock.
Figure 14-1 shows the outline of the serial interface.
This serial interface is of two-wire/three-wire serial I/O type. The former type uses SCK and SO1/SI pins. The
SO1/SI/P0B3
SCK/P0B2
SO0/P1C0
2. SIOTS (bit 0 of serial I/O mode select register. Refer to Figure 14-3) starts/stops communication.
3. SIOHIZ (bit 1 of serial I/O mode select register. Refer to Figure 14-3) sets the function of the SO0/
4. SIOSEL (bit 3 of serial I/O mode select register. Refer to Figure 14-3) selects I/O of SO1/SI/P0B3
P1C0 pin.
pin.
SIOCK1, 0 flags
Clock I/O
control block
Data I/O
control block
SIOHIZ flag
SIOSEL flag
Figure 14-1. Outline of Serial Interface
Clock control block
Clock counter
Wait signal
OUT
Count value 8
75 kHz
Presettable shift register
(SIOSFR)
Wait control
block
SIOTS flag
PD17072,17073
IRQSIO flag
IN