Silan

Semiconductors

SC9256

HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD

REV: 1.0

2002.01.30.

13

Address D1H

MSB

BUSY

OVER

"0"

"0"

General-purpose counter

option monitor bit

General-purpose counter

overflow detection bit

General-purpose counter

busy

Counted value in general-

purpose counter

General-purpose counter

ended counting

Counted value in general-

purpose counter

(Overflow state)

BIT DATA = "1"

BIT DATA = "0"

Note: When using the general-purpose counter, before referring to the contents of the general-purpose counter

result bit (f0~f9), confirm that the busy bit is “0” (counting is ended) and the OVER bit is “0” (general-purpose

counter data are normal).

(6) START bit…When the data are set to “1”, the general-purpose counter is reset then counting begins.

LSB

MSB

Address D2H

start

0

1

Counting continues uninterrupted.

Counting begins after general - purpose counter is reset.

2.

General-purpose counter circuit configuration

The general-purpose counter section consists of input amps, a gate time control circuit and a 20 bit binary

counter.

OVER

Amp

IF

IN1

IF

IN2

20bit binary counter

Overflow detection

Gate time control circuit

Cycle measurement

pulse

Gate

SC

IN

(CMOS input)

SC IF1

IF2

START

G0

G1

BUSY

f0-f19

Fig.5

3. General-purpose counter measurement timing