Electronics America 4-Bit Single-Chip Microcomputer User's Manual

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CHAPTER 5. PERIPHERAL HARDWARE FUNCTIONS
Fig. 5-51 Data Transmission from Master Device to Slave Device
Program
Processing
Hardware
Operation
Master Device Processing
(Transmission Side)
Transfer Line
SCK Pin
SB0 Pin
Slave Device Processing
(Reception Side)
Program 
Processing
Hardware
Operation
Serial Receive Operation
Serial Transmit Operation
Write
to SIO
1
2 3 4 5
6
87 9
D7
D6
D5 D4
D3
D2 D1 D0
Data
Interrupt Servicing
(Preparation for Next Serial Transfer)
IRQCSI
Genera-
tion 
ACKD
Setting
SCK
Stop-
page
READYBUSY
ACK
ACKT
Setting
SIO
Read
IRQCSI
Genera-
tion
ACK
Output
BUSY
Output
BUSY
Clear-
ance
BUSY
Clear-
ance