Edgetech PORT LF, Руководство пользователя по оборудованию

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2.3.2 BACS Command Structure
The BACS’ command structure consists of two 8-bit words separated by 5-sec intervals. Each bit encoded
word is comprised of 8 bits from a 16-bit command. The 16-bit command is a 15 bit, 11 block cyclic code
with an overall parity bit appended to the end to form a 16-bit code with a minimum Hamming distance
of 4 bits. Additionally, two transitions are required within each word, and no repetitions of words are
allowed per command.
2.3.3 BACS Command Coding
BACS command coding is described in the following table:
PAIR NUMBER “0” “1”
1 9.5 kHz 9.9 kHz
2 9.5 kHz 10.3 kHz
3 9.5 kHz 10.7 kHz
4 9.9 kHz 10.3 kHz
5 9.9 kHz 10.7 kHz
6 10.3 kHz 10.7 kHz
Table 2-4: BACS Command Coding
2.3.4 Standard Command Functions
Functions for the three standard commands are given in the table below:
COMMAND FUNCTION
ENABLE Enable Transponder
DISABLE Disable Transponder
RELEASE Activate mechanical release
Table 2-5: Standard Command Functions
2.3.5 Transponder Specifications
Specifications for the transponder are given below:
SPECIFICATION VALUE
Sensitivity 80 dB re 1 µPa
RCV Detection Jitter < 0.1 ms
Interrogate Frequency 9 or 11 kHz standard (others are optional)