三合微科股�½有限公司
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AM
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Microelectronics Corp.
SM5221-001/002
32 KEYS ENCODER
TRANSMISSION CODE
(1) DOUT Output
The transmission code consists of a leader code, 16-bit custom code, and 8-bit data code.
The inverse code of the data code is also sent simultaneously, giving a total configuration
of 32 bits per transmission.
C0 C1 C2 C3 C4 C5 C6 C7 C0' C1' C2' C3' C4' C5' C6' C7' D0 D1 D2 D3 D4 D5 D6 D7 D0 D1 D2 D3 D4 D5 D6 D7
Leader
Code
Custom Code
Custom Code'
Data Code
Data Code
DOUT Output Code
The leader code consists of a 9 ms carrier waveform plus a 4.5 ms OFF waveform, and is
used as the leader for the following code. The code uses the PPM (Pulse Position
Modulation) method, with "1" and "0" differentiated by the time between pulses reference
following diagram. Each code consists of 8 bits, and simultaneous transmission of the
inverse code.
9 ms
4.5 ms
Custom Code'
Custom Code
8 bits
8 bits
18 ms to 36 ms
58.5 to 76.5 ms
Data Code
8 bits
Data Code
8 bits
13.5 ms
Leader
Code
0.56 ms
0.56 ms
2.25 ms
Bit 1
1.125 ms
Bit 0
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V.2.0 Mar 8,2002