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2 udcs: count status register – FUJITSU MB91460 SERIES FR60 User Manual

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Chapter 41 Up/Down Counter

4.Register

4.2 UDCS: Count Status Register

This register is used to control Up/Down Counter and to indicate the status of the counter.

• UDCS0 (Up/Down Counter 0): Address 0307

H

(Access:

Byte, Half-Word

)

• UDCS1 (Up/Down Counter 1): Address 030B

H

(Access:

Byte, Half-Word

)

• UDCS2 (Up/Down Counter 2): Address 0317

H

(Access:

Byte, Half-Word

)

• UDCS3 (Up/Down Counter 3): Address 031B

H

(Access:

Byte, Half-Word

)

(For attributes, refer to “

Meaning of Bit Attribute Symbols (Page No.10)

”.)

• bit7: Enable count operation

• bit6: Enable compare interrupt requests

Setting the interrupt request permission bit to “1” enables the interrupt request flag (CMPF).

• bit5: Enable overflow/underflow interrupt requests

Setting the interrupt request permission bit to “1” enables the interrupt request flag (OVFF or UDFF).

• bit4: Compare detection flag

To enable interrupt requests, the interrupt request permission bit must be set (CITE= “1”).

• bit3: Overflow detection flag

To enable interrupt requests, the interrupt request permission bit must be set (UDIE= “1”).

• bit2: Underflow detection flag

7

6

5

4

3

2

1

0

bit

CSTR

CITE

UDIE

CMPF

OVFF

UDFF

UDF1

UDF0

0

0

0

0

0

0

0

0

Initial value

R/W

R/W

R/W

R/W0

R/W0

R/W0

R/WX

R/WX

Attribute

CSTR

Count operation

0

Disable count operation.

1

Enable count operation. (Activate counter.)

CITE

Compare interrupt request

0

Disable compare interrupt requests.

1

Enable compare interrupt requests.

UDIE

Overflow/underflow interrupt request

0

Disable overflow/underflow interrupt requests.

1

Enable overflow/underflow interrupt requests.

CMPF

Compare detection

When read:

When written:

0

Comparison results do not agree.

Clear the flag.

1

Comparison results agree.

Disable setting.

OVFF

Overflow detection

When read:

When written:

0

No overflow

Clear the flag.

1

An overflow has occurred.

Disable setting.

UDFF

Underflow detection

When read:

When written:

0

No Underflow

Clear the flag.

1

An underflow has occurred.

Disable setting.