Specifications

D17XX OEM Integration v0.1
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Domo Limited doing business as Cobham Surveillance
 rtsp:// unit_ip_address /record.sdp
 e.g. rtsp://192.168.2.193/record.sdp
Note: Simultaneous recording and playback is NOT supported at this stage and will lead to stuttery
recording and playback and possibly corrupt the recording.
9. Direct connection to PC
 Should there be a need for direct connection to a PC without a network, DHCP should be
disabled on the D17XX and the user should assign a static IP address to the unit.
 Power down the unit and connect to the PC’s Ethernet port via J14.
 Configure the PC to have TCP/IP DHCP disabled, and assign a static IP address to the PC
in the same network IP class as the D17XX.
 Power up the D17XX and observe the assigned IP address in Tera Term. From the PC,
browse to the address, as described in the previous section.
10. Serial RS232 Control
The following section describes the control protocol employed on the RS232 link for controlling the
D550 board.
RS232 Control – General Principles
The physical interface is RS232 but this can be converted to RS485 with an external adapter where
multiple units are controlled over one RS 485 bus.
Normal operation involves sending a packet from the control device (normally a PC) to the device
being controlled. If the packet satisfies an address integrity check, then the controlled device will
action the command and send a reply.
For compatibility with modems an ASCII style protocol is used.
Ports are set for 115200 baud, 8 bits, No parity, 1 stop.
Command Packet Structure
ASCII Value
STX 02h Start byte
0-9 30h-39h 4 byte unit address. In range 0-9999
R 20h-7Eh 1 byte command type. r read, w write
ABCD 20h-7Eh Command –four byte mnemonic
; 3Bh Separator
PQR 20h-7Eh Data –Optional, variable length
; 3Bh Separator
X 80h-FFh Checksum
ETX 03h End byte
Reply Packet Structure
ASCII Value
STX 02h Start byte
0-9 30h-39h 4 byte unit address. In range 0-9999