AN118
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Packet
Data0
Data1
Data2
Data3
Packet Decoded
Figure 39. DATA0 – DATA3 Status When Pulse Mode is Off
Packet
Data0
Data1
Data2
Data3
Pulse Time
Packet Decoded
Figure 40. DATA0 – DATA3 Status When Pulse Mode is On
5.3 Bit Format
In 1920 packet, a single data bit can be constructed (encoded) by 3, 4, 5 or 6 symbols. The user must configure this parameter
according to the bit format of the transmitter. For the conventional 1527 packet, the bit format is 4 symbols/bit. For the 2262
packet, this parameter is unavailable and the bit format is fixed at 8 symbols/bit.
5.4 Valid Reception
This defines how many identical packets the device consecutively received represent a valid reception. For example, if it is set to
2 packets, the device only updates the values of the data pins after consecutively receiving 2 identical valid packets. Setting this
parameter to 4 packets leads to the highest reliability of the communication with most time and power consumed in each
transmission.
The below are some computation of the packet length and the time consumption.
If “4 symbols per bit” is used as the “Bit Format”, and the “Sync ID Length” is set to 24, the entire 1920 normal packet contains 16
(Preamble) + 32 (Head_N) + 4 x 24 (Sync ID) + 4 x 4 (D0, D1, D2, D3) + 8 (CRC) = 168 symbols. The study packet contains 16
(Preamble) + 32 (Head_S) + 4 x 24 (Sync ID) + 8 (CRC) = 152 symbols.
If the “Symbol Rate” is set to 4.8 ksps, it takes about 35 ms to transmit/receive an entire 1920 normal packet and 31.66 ms to
transmit/receive an entire 1920 study packet.
It shall be reminded that, in this case, the 35 ms is the minimum time for the receiver to respond to the transmitter after the user
