SC9243

FUNCTIONAL DESCRIPTION

1. TRANSMISSION CODE

The transmission code consists of a leader code, 16 bits system code, and 8 bits data code. The inverse of the

data code is also sent simultaeously. The following diagram shows this one frame construction.

It should be noted that System Code Bit 7(S7) has a fixed value of “1”.

The leader code consists of a 4.5 ms carrier waveform followed by a 4.5 ms OFF waveform. It is used as the

leader for the following codes. Thus, when reception is configured by a microcomputer, the time relationship

between the detection of the reception and the other processes can be managed efficiently. The code uses the

PPM (Pulse Position Modulation )Method, with “0”and “1” differentiated by the time between pulses.

2. REMOTE OUTPUT WAVEFORMS

SC9243 Remote Output Waveforms are given in the diagram below.(for fosc=455KHz)

When oscillation frequency is 455 KHz, a signal is outputted after pulse is modulated by 38 KHz of duty 1/3

(which is 1/12 of the carrier generation circuit).

Note:

In preparing the firmware of the receiving circuit, please strictly follow the following instructions:

1. System Codes: The same code is transmitted twice and therefore, always decode these 2 codes and check

if they are in agreement with each other.

2. Key Data Codes: The Key Data Code and its inversed code are always transmitted together, therefore,

check if they are in agreement with each other.

HANGZHOU SILAN MICROELECTRONICS CO.,LTD

REV:1.2

2009.02.17

Http: www.silan.com.cn

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