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E.2.1 packet structure, E.2.2 start of packet, E.2.3 address – Comtech EF Data KST-2000A/B User Manual

Page 155: E.2.4 instruction code

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Ku-Band Satellite Transceiver

Revision 9

FSK Remote Control Commands

MN/KST2000AB.IOM

E–3

E.2.1

Packet Structure

Controller-to-target:



Example: <0135/TFQ=70.2345{CR}

Target-to-controller:



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

Each of the components of the packet is now explained.

E.2.2

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.

E.2.3 Address

The terminal address is fixed as: Modem Address +1

IMPORTANT

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.

E.2.4 Instruction

Code

This is a three-character alphabetic sequence which identifies the subject of the message.
Wherever possible, the instruction codes have been chosen to have some significance.

For example: UFQ for uplink frequency, DAT for downlink
attenuation. This aids in the readability of the message, should it be
displayed in its raw ASCII form. Only upper case alphabetic
characters may be used (A-Z, ASCII codes 65 - 90).