Comtech EF Data CDM-Qx, Инструкция по установке и эксплуатации

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CDM-Qx Satellite Modem Revision 6
Remote Control MN/CDMQx.IOM
C.4 Packet Structure
Controller-to-target:
Start of Packet
Target
Address
Address
De-limiter
Instruction
Code
Code Qualifier
Optional
Arguments
End of Packet
<
ASCII code 60
(1 character)
(4 characters)
/
ASCII code 47
(1 character)
(3 characters)
= or ?
ASCII code 61 or 63
(1 character)
(n characters)
Carriage Return
ASCII code 13
(1 character)
Example: <0135/TRQ=70.2345{CR}
Target-to-controller:
Start of Packet
Target
Address
Address
De-limiter
Instruction
Code
Code Qualifier
Optional
Arguments
End of Packet
>
ASCII
code 62
(1 character)
(4 characters)
/
ASCII
code 47
(1 character)
(3 characters)
=,?,!,*,# or -
ASCII code 61,
63,33,42,35,
126
(1 character)
(From 0 to n
characters)
Carriage Return,
Line Feed
ASCII code 13,10
(2 characters)
Example: >0654/RSW=32{CR} {LF}
Explanations for each of the components of the packet follow.
C.4.1 Start Of Packet
Controller-to-Target: This is the character ‘<’ (ASCII code 60)
Target-to-Controller: This is the character ‘>’ (ASCII code 62)
Because this is used to provide a reliable indication of the start of packet, these two
characters may not appear anywhere else within the body of the message.
The controller sends a packet with the address of a target – the destination of the packet.
When the target responds, the address used is the same address to indicate to the
controller the source of the packet. The controller does not have its own address.
C.4.2 Address
Up to 9999 devices can be uniquely addressed. The RS-485 base address is set by the
front panel; the RS-232 base address is always zero. Each plug-in slot (as viewed from
the back of the chassis) has its own address.
Slot Address
Upper Left Base
Lower Left Base + 1
Upper Right Base + 2
Lower Right Base + 3
C-3