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Note: Not all commands apply to all models of DVR’s.
Message Format
<BOM><ID>:<Class>:<Code>[:Operands]:<Checksum>[EOM]
Where…
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Symbol
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Value
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Description
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:
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:
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Field delimiter
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<BOM>
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@
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Beginning of message (for command)
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<
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Beginning of message (for reply)
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<ID>
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00~99
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Device ID
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<Class>
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DR
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Device Class (“DR” for DVR systems)
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<Code>
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AA~zz
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Op-code (see below)
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<Operands>
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Optional operands defined for each operation
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<Checksum>
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00~99
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Checksum (sum of ASCII codes before checksum discarding overflow)
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*
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No checksum
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[EOM]
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^J^M
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End of message (optional: only for convenience of users using general terminal)
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*) All digits are used in decimal format.
*) Letters are case sensitive.
Control Flow
Every transaction consists of one command and one reply.
Characters transmitted before <BOM> are ignored.
The format of operands is defined independently for each op-code.
The <BOM> received before <Checksum> of previous message resets interpretation: i.e., discards the previous message. EXCEPTION: in case of text input, none of characters within specified length has special interpretation.
Common Reply
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Reply code
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Reply data
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Description
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ok
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er
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0000~9999
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Error: return error number
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Example
Send @01:DR:FP:18:N:* (Unit ID 1 / menu button push) This is the same as pressing the menu button on the front panel of the DVR. When you finish sending the “*” you will get the response <01:DR:ok:99 at the end of the string if the DVR has received the command.
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