Approach Tech DVR-3024M, DVR-3024MD manual Miscellaneous, RS-232 & RS-485 Setup & Protocol

6.MISCELLANEOUS

6.MISCELLANEOUS

6.1 RS-232 & RS-485 Setup & Protocol

6.1.1 RS232 & RS485 Setup

Use a Null Modem cable (the standard RS-232 9 Pin Cable with Pin 2 and Pin 3 exchanged, see pin configuration chart below for details) to connect the COM 1 on the rear panel of the DVR to a PC.

Set the RS-232option to ON in the COMMUNICATION page of the setup menu. Set the PC communication parameters: 9600 bps, No Parity, 8 Data Bits, 1 Stop Bit.

6.1.2Communication Protocol

6.1.2.0General Command Format

<Lead Code = 0x41>, < Dest ID >, < Src ID >, <Main category >, <Second category >, {<Number of parameters>, <Parameter 1>, <Parameter 2> ..,} <End Code= 0x4f>

Lead Code	= 0x41
Dest ID	= 0x01
Src ID	= 0x20
Main Category = 0x01		Keys and Signals
	= 0x02	Command

Second Category = 0x01 Handshake

=0x02 Request Time/Set Time

=0x06 Request System State

=0x0b Time Search

=0x10 Request HDD Info

=0x11 Request REC Position

=0x12 Playback Immediately

End Code= 0x4f

The different command types and their corresponding parameters are as follows:

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