Silan

Semiconductors

SC9148B

HANGZHOU SILAN MICROELECTRONICS CO.,LTD

Rev: 2.1

2002.09.10.

5

Data of C1 , C2 and C3 code bit become “1” when diodes are connected to CODE Terminal through Timing

Signal Terminals T1 ~T3, and ‘0’ when not connected . (In the above diagram , C1 , C2 and C3 are “1” , “1” and “1”

data . )

The SC9148P has 3 code bits . However , the SC9149P that is a receiving IC ( DIP 16 PIN ) and the SC9150P

(DIP 24 PIN ) are able to use only C2 and C3 , and C1 and C2 2 code bits , respectively .

Therefore , diodes must be connected so that code bit data of the SC9148P agreement with the receiving IC .

Note : For C3 and C1 code bit data not used on the SC9150P and SC9149P , it is necessary to transmit ‘1’ and

diodes must be so connected .

6. TRANSMITTING WAVEFORM

6.1 BASIC TRANSMITTING WAVEFORM (at fosc=455kHz)

a

3a

48a

C1

C2

C3

H

S1S2K1K2

K3K4K5K6

C1~C3: CODE BIT READER

H,S1,S2: HOLD/SINGLE PULSE READER

K1~K6:

KEY INPUT READER

Basic transmitting waveform is 12-bits serial data in configuration as shown above.

The time of each bit “ a” is decided as shown below by oscillation frequency fosc by means of XT and non-XT.

a=(1/fosc)

×192(sec)

6.2 DISTINCTION OF BIT “0” AND “1”

a

3a

BIT "0"

BIT "1"

0

1

01

0

0

1

0

01

0

0

One word of the above transmission command is in the configuration of (010100100100).