UPD784035YGC NEC, UPD784035YGC Datasheet - Page 42

• Manufacturer Part Number: UPD784035YGC
• Description: 16-/8-BIT SINGLE-CHIP MICROCONTROLLERS
• Manufacturer: NEC

42
SCK1, SCK2
(2) 3-wire serial I/O mode
Remark f
SO1, SO2
SI1, SI2
In this mode, the master device starts transfer by making the serial clock active and transfers 1-byte data
in synchronization with this clock.
This mode is used to communicate with a device having the conventional clocked serial interface. Basically,
communication is established by using three lines: one serial clock (SCK) and two serial data (SI and SO)
lines.
Generally, a handshake line is necessary to check the communication state.
n = 0 through 11
m = 1 or 16 through 30
XX
: oscillation frequency or external clock input
Figure 7-11. Block Diagram in 3-wire Serial I/O Mode
Direction control circuit
Serial clock counter
control circuit
Shift register
Serial clock
Internal bus
PD784035Y, 784036Y, 784037Y, 784038Y
SIO1, SIO2
Output latch
generation circuit
Interrupt signal
1/m
1/2
INTCSI1,
INTCSI2
n+1
f
XX
/2