UPD17073 NEC, UPD17073 Datasheet - Page 123

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

14.9 Operational Outline of Serial Interface
Item
Status of
each pin
Program counter
Operation of
presettable
shift register
Tables 14-3 and 14-4 outline the operations of the serial interface.
Operation mode
SCK/P0B2
SI/SO1/P0B3
SO0/P1C0
Output
Input
– – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – –
– – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – –
• When P0BBIO2 = 0
• When P0BBIO2 = 1
• When P0BBIO3 = 0
• When P0BBIO3 = 1
Waits for serial output
Incremented at falling edge of SCK pin
• When SIOHIZ = 0
• When SIOHIZ = 1
• When SIOSEL = 0
General-purpose input port
General-purpose output
port
General-purpose input port
General-purpose output
port
Not output
Shifted from MSB and output from SO0 pin at falling edge of SCK pin
Shifted from LSB and status of SI pin is input at rising edge of SCK pin.
If SI pin is set in output mode, however, contents of output latch are input.
During wait (SIOTS = 0)
Slave operation (SIOCK1 = SIOCK0 = 0)
Table 14-3. Operation in 3-wire Serial I/O Mode
• When P0BBIO2 = 0
• When P0BBIO2 = 1
• When P0BBIO3 = 0
• When P0BBIO3 = 1
Serial output
Wait released (SIOTS = 1)
External clock input port
General-purpose output
port
Serial input
General-purpose output
port
SIOSEL = 0
SIOHIZ = 1
• When P0BBIO2 = 0
• When P0BBIO2 = 1
• When P0BBIO3 = 0
• When P0BBIO3 = 1
Waits for serial output
General-purpose input port
Waits for internal clock
output
General-purpose input port
General-purpose output
port
During wait (SIOTS = 0)
Master operation (SIOCK1 = SIOCK0 = other than 0)
PD17072,17073
• When P0BBIO2 = 0
• When P0BBIO2 = 1
• When P0BBIO3 = 0
• When P0BBIO3 = 1
Serial output
Wait released (SIOTS = 1)
General-purpose input port
Internal clock output
Serial input
General-purpose output
port
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