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26 shift clock frequency setting (39h), 27 irqnc (3fh) – NEC PD17062 User Manual

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87

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PD17062

9.26 SHIFT CLOCK FREQUENCY SETTING (39H)

9.27 IRQNC (3FH)

IRQNC is an interrupt request flag that indicates the interrupt request state.

When an interrupt request is generated, the flag is set to 1. When the request is accepted (interrupt is made),

the flag is reset to 0.

The interrupt request flag can be read and written by the program. Hence, if 1 is written, an interrupt by

software can be generated. If 0 is written, the interrupt hold status can be released. The IRQNC flag becomes

0 upon reset.

b

3

b

2

b

1

b

0

SIO0CK3

SIO0CK2

SIO0CK0

39H

SIO0CK1

0

0

0

1

1

0

1

1

100 kHz

200 kHz

500 kHz

1 MHz

Fixed at 0

Internal clock frequency

Flag name

Bit position

Interrupt source

IRQNC

b

0

INT

NC

pin

IRQBTM0

b

1

Clock timer

IRQVSYN

b

2

V

SYNC

pin

IRQSIO0

b

3

Serial interface