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@lachesis
Created March 18, 2024 15:12
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Alarm reporting protocols described by KJ7BZC
Contact ID, Ademco High Speed, Ademco Express:
-dualtone handshake
-1400hz acknowledgement
-10 digits per second dtmf data
Acron, Scancom/Scantronic 4+3+3, FBI Superfast, DSC/SG 4+3:
-2300hz handshake
-2300hz acknowledgement
-10 digits per second dtmf data
pulse formats (3+1, 3+2, 4+1, 4+2, etc):
-1400hz or 2300hz handshake
-acknowledgement matches handshake
-data is pulsed tones like rotary dialing at either 10, 15, 20, or 40 baud, first number in the format name is the amount of account digits and the second is the amount of zone/event digits. May be sent as either two rounds where the receiver compares them to confirm the data is valid, or a checksum digit at the end.
SIA:
-bell 103 answering tones on the receiver
-bell 103 originating tones on the panel
-110 or 300 baud, uses a preamble followed by ASCII encoded report data alongside a column parity and length indicator for error detection.
BFSK:
-2300hz handshake
-2300hz acknowledgement
-45.45 baud FSK data with a proprietary encoding, equivalent data format to 3+1 extended plus status reports and listen-in signals
Modem II:
-bell 103 or ccitt answering tones on the receiver
-bell 103 or ccitt originating tones on the panel
-110 baud fixed length binary data with a checksum, encoding is very similar to BFSK except it can report longer zone numbers and has diagnostic reports as well
Modem IIe/Modem IIIa2/Modem4:
-bell 103 answering tones on the receiver
-bell 103 originating tones on the panel
-300 baud variable length data with a checksum and length indicator for error detection. Reports account number lengths from 2-10 digits, a basic event type followed by additional blocks for zone/user/sdi address/whatever numbers, and optionally ascii data for zone/user names
Robofon:
-1000hz ASK from the receiver
-1000hz ASK from the panel
-reports a 6 digits account number alongside a two digit event code, can’t remember the baudrate off the top of my head, checksum for error detection
Seriee FSK:
-CCITT answering tones from the receiver
-CCITT originating tones from the panel
-300 baud fixed length data sent as double round for error detection, sends a variable length account number followed by either a listen-in signal or a two-digit event code
that’s all the ones I’ve ever really dealt with, alongside ITI format, which is 110 baud bell 103 with a checksum, sends a two-byte field and a 5 digit account number. Each bit in the field indicates a different event type if it’s set
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