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2 SYM
2 SYM
1 SYM
1 SYM
Bit 1
Bit 0
1 SYM
1 SYM
3 SYM
3 SYM
Bit 1
Bit 0
3 SYM
2 SYM
Bit 1
2 SYM
3 SYM
Bit 0
2 SYM
1 SYM
Bit 1
1 SYM
2 SYM
1 SYM
1 SYM
Bit 0
1 SYM
3 SYM
3 Symbols/Bit
4 Symbols/Bit
5 Symbols/Bit
6 Symbols/Bit
Figure 30. 1920 Bit Format Options
It must be noticed that the Bit Format setting of the receiver and the transmitter must be identical. In order to reduce the length of
the entire packet and therefore increase the reliability and robustness of the wireless communication between the receiver and
the transmitter, it is recommended to select 3 or 4 symbols per bit.
5.1.4 1527 Normal Packet Structure
The traditional 1527 packet contains a 32-symbol Sync, a 20-bit Address (Sync ID) and 4-bit Data. CMOSTEK has defined a
1527 Study Packet to support the ID study in 1527 mode. The traditional packet introduced here is called the “1527 Normal
Packet”.
Figure 31. 1527 Normal Packet Structure
Table 12. Configurable Parameters in 1527 Packet
Parameter
Descriptions
Default
Mode
Sync
The Sync is 1 high symbol followed by 31 low symbols. The
user can determine whether or not to introduce tolerance of
detecting the 31 low symbols. The options are: No Tolerance,
+/- 6 symbols, +/- 13 symbols, or +/- 20 symbols.
+/- 13 symbols
Basic
Advanced
Address (Sync ID)
Value
The range of the value is from 0 to 2
20
-1. This is because the
Sync ID Length is fixed at 20 for 1527.
0
Basic
Advanced
In the traditional 1527 format, 8 OSC clocks are equal to 1 LCK, 4 LCK are equal to 1 symbol. By using the CMT2250A pairing
with CMT2150A, the user does not need to adjust the OSC to determine the symbol rate, because the symbol rate is directly
programmed. The Bit Format is fixed at 4 symbols (16 LCK) per bit.
