Silan

Semiconductors

SC9302 Series

HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD

Rev: 2.0

2001-11-01

16

11. DOUT BCD CODE

When dialing, the corresponding 4-bit BCD codes are serially presented on DOUT from MSB to LSB. The data of

the DOUT is valid at the falling edge of the CLOCK pin. The following table lists the BCD codes corresponding to the

keyboard input.

Key-In

BCD Code

Key-In

BCD Code

1

0001

8

1000

2

0010

9

1001

3

0011

0

1010

4

0100

*/T

1101

5

0101

#

1100

6

0110

F

1011

7

0111

P

1110

12. LOCK FUNCTION

The function aims to detect locked dialing number to prevent a long distance call. The dialing output of the chip is

disabled if the first input key after on-off-hook is the locked number when the lock function is enabled. The lock

function selection is listed below.

The SC9302X version is the pin-selected type; on the other hand, the SC9302XLT is the key-board operated type.

However, the SC9302XT version does not support any lock function.

• SC9302X VERSION

LOCK Pin

Function

OPEN

Normal dialing (no lock)

V

DD

“0, 9” is inhibited

Vss

“0” is inhibited

• SC9302XLT VERSION

Function

No

No

Keyboard operated IDD lock

No

Yes

Lock 0

Yes

No

Lock 0,9

Yes

Yes

All keys are locked