CiM-550 IP Enabled Satellite Modem

Rev. 2

Serial Remote Control

CD/CIM550.IOM

5.5PACKET STRUCTURE

Controller-to-target:

Start of

Target

Address

Instructio

Code

Optional

End of

Packet

Address

De-limiter

n

Qualifier

Arguments

Packet

 

 

 

Code

 

 

 

<

 

/

 

= or ?

 

Carriage

ASCII

 

ASCII code

 

ASCII code

 

Return

code 60

 

47

 

61 or 63

 

ASCII code 13

 

 

 

 

 

 

(1 character)

(1

(4

(1

(3

(1 character)

(n

 

character)

characters)

character)

characters)

 

characters)

 

Example:

<0135/TFQ=70.2345{CR}

 

 

 

Target-to-controller:

 

 

 

 

 

 

 

 

 

 

 

 

Start of

Target

 

Address

Instruction

Code Qualifier

Optional

End of Packet

Packet

Address

 

De-limiter

Code

 

Arguments

 

>

 

 

/

 

=, ?, !, or *

 

Carriage

ASCII

 

 

ASCII

 

ASCII code 61,

 

Return, Line

code 62

 

 

code 47

 

63, 33 or 42

(From 0 to n

Feed

(1 character)

(4 characters)

(1 character)

(3 characters)

(1 character)

characters)

ASCII code

 

 

 

 

 

 

 

13,10

 

 

 

 

 

 

 

(2 characters)

 

 

 

 

 

 

 

 

Example: >0654/RSW=32{CR}{LF}

Each of the components of the packet is explained below.

5.5.1START OF PACKET

Controller to Target: This is the character ‘<’ (ASCII code 61)

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.

5.5.2ADDRESS

Up to 9,999 devices can be uniquely addressed. In EIA-232 applications this value is set to 0. In EIA-485 applications, the permissible range of values is 1 to 9999. It is programmed into a target unit using the front panel keypad.

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

IMPORTANT own address.

57