UPD17073 NEC, UPD17073 Datasheet - Page 117

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

14.5 Presettable Shift Register
I/O pin in synchronization with the falling edge of the shift clock, and reads data to its least significant bit (LSB) in
synchronization with the rising edge of the shift clock.
14.6 Wait Control Block
is started.
clock rises at clock counter “8”.
the SIOTS flag.
wait status.
Note
The presettable shift register is an 8-bit shift register that writes serial-out data and reads serial-in data.
Writing/reading data to/from the presettable shift register is performed by PUT and GET instructions via data buffer.
The presettable shift register outputs (transmits) the content of its most significant bit (MSB) from the serial data
Figure 14-4 shows the configuration and function of the presettable shift register.
The wait control block performs wait (pause) control of communication.
By releasing the wait status by using the SIOTS flag of the serial I/O mode select register, serial communication
After the wait status has been released, and communication has been started, the wait status is resumed if shift
The communication status can be detected by the SIOTS flag.
That is, the communication status can be detected by detecting the status of the SIOTS flag after setting “1” to
If “0” is written to the SIOTS flag while the wait status is released, the wait status is set. This is called a forced
For the configuration and function of the serial I/O mode select register, refer to Figure 14-3.
Don't care
DBF3
If the PUT or GET instruction is executed during serial communication, the data may be lost. For details,
refer to 14.8 Notes on Setting and Reading Data.
shift register
Presettable
Don't care
Name
DBF2
Figure 14-4. Configuration of Presettable Shift Register
Data buffer
b
M
S
B
D7 D6 D5 D4 D3 D2 D1
7
b
DBF1
6
Peripheral register
b
5
Transfer data
Valid data
b
4
8
b
3
b
DBF0
2
b
1
GET
PUT
b
S
B
L
D0
0
Note
Note
Symbol
SIOSFR
Setting of serial-out data and reading of
serial-in data
D7
Serial out
Peripheral address
D6
03H
D5
D4
PD17072,17073
D3
D2
Serial in
D1
D0
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