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1 start of packet, 2 target address, 3 address delimiter – Comtech EF Data CDM-760 User Manual

Page 238

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Serial-based Remote Product Management

Revision 2

CDM-760 Advanced High-Speed Trunking Modem

MN-CDM760

8–4

Target-to-Controller (Response to Command or Query)

Start of Packet

Target Address

Address Delimiter

Instruction Code

Code Qualifier

Optional Arguments

End of Packet

>

ASCII Code 62

(1 character)

0000 (default)

(4 characters)

/

ASCII Code 47

(1 character)

(3 characters)

= , ?, !, *, #, ~

(ASCII Codes 61, 63,

33, 42, 35, or 126)

(1 character)

(n characters)

Carriage Return

ASCII Code 13

(1 character)

Packet example – response received for issued query:

>0000/TMC = 10[cr][lf]

Detailed description of the packet components follow.

8.4.2.1 Start of Packet

The ‘<’ and ‘>’ characters indicate the start of an issued or received packet. They may not appear anywhere else within the body of the message.

Controller-to-Target: This is the character ‘<’ (ASCII Code 60).

Target-to-Controller: This is the character ‘>’ (ASCII Code 62).

8.4.2.2 Target Address

The Target Address designates the packet destination. The Controller does not have its own address. After the Controller sends a packet with the

designated Target Address, the Target responds to the Controller, using this same address, to indicate the source of the packet.

• In EIA-232 applications, this value is set to 0000.

• In EIA-485 applications, the permissible range of values is 0001 to 9999.

8.4.2.3 Address Delimiter

This is the “forward slash” character '/ ' (ASCII Code 47).