AS3933-AN01
Demoboard Description
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Revision 1.1/ 24/02/13
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5.2.10 Frequency Detection Tolerance
The Frequency Detection Tolerance can be tighter or more relaxed. For details please see the
datasheet.
5.2.11 General Settings
•
Enable sensitivity boost: The channel amplifier gain is boosted to +3dB.
•
AGC only on carrier burst: The automatic gain control is acting only on the first carrier burst.
•
AGC UP-DOWN: The automatic gain control is operating in both directions (up and down).
At the beginning the gain of the channel amplifier is set to the maximum and the AGC
reduces it according to the received signal input level. If AGC UP-DOWN is disabled the
AGC can only decrease the gain for the whole duration of the data reception. In this mode
the system holds the RSSI peak.
•
Mask data before wakeup: During the pattern correlation it is possible to display the data
(received pr pattern) on the DAT pin, if this bit is disabled. Otherwise, this will be
masked. In case the user decides to mask the data before the generation of the interrupt on
the pin WAKE, then the data will be displayed only after the generation of the interrupt.
•
Display clock generation: The clock generator output signal is displayed on CL_DAT pin.
5.2.12 Wakeup Pattern (Manchester)
Select the wake-up pattern here. Each field defines 4 bit. If the transmitted pattern matches the
selected pattern, a wake-up interrupt is generated at the WAKE pin. The WAKE pin goes high.
5.2.13 Correlator
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Enable Correlator: If the Correlator is enabled the chip searches first for the preamble bits
and then for data pattern (Manchester encoded wake-up pattern). Should the pattern
correlation be disabled, the AS3933 goes directly into the data receiving mode.
•
Enable Manchester decoder: If the Manchester decoder is enabled the data on the DAT pin
can be directly read binary. In addition, the recovered clock is presented on the CL_DAT
pin.
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Manchester Pattern Length: the Manchester pattern length can be selected between 16bit
and 32bit. The possible selection of the wake-up pattern (Manchester) is changed
accordingly.
•
16 bit pattern length: Each field of the wake-up pattern defines 4 bit, which are directly
Manchester encoded.
Example: 9 6 6 9 (Manchester)
1001 0110 0110 1001 (binary, Manchester conform);
sum = 16bit
•
32 bit pattern length: Each field of the wake-up pattern identifies 4 bit, which are
hexadecimal encoded. Each bit defines one Symbol and is converted to Manchester by the
microcontroller in the second step.
Example: 7 B A 5 (Symbol)
0111 1011 1010 0011 (binary)
10010101 01100101
01100110 10100101 (binary Manchester conform); sum = 32 bit
•
Single pattern: The wakeup pattern is sent as single string.