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Address, Instruction code, Instruction code qualifier – Comtech EF Data LCS-4 User Manual

Page 68: A.2.1.2 a, A.2.1.3 i, A.2.1.4 i

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LCS-4 L-Band Combiner Switch

Revision 1

Remote Control Operation

MN/LCS4.IOM


A.2.1.2 A

DDRESS

Up to 9999 devices can be uniquely addressed. In RS-232 and RS-485 applications, the
permissible range of values is 1 to 9999. It is programmed into a slave unit using the Set
Physical Address (SPA) command.

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.

A.2.1.3 I

NSTRUCTION

C

ODE

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

For example: BSA for BUC power supplies A, LCB for LNB Current window B,
etc. 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).

A.2.1.4 I

NSTRUCTION

C

ODE

Q

UALIFIER

This is a single character that further qualifies the preceding instruction code.
Code Qualifiers obey the following rules:

1. From Controller to Target, the only permitted values are:

= (ASCII code 61)

? (ASCII code 63)


They have these meanings:
The = code (controller to target) is used as the assignment operator, and is used to
indicate that the parameter defined by the preceding byte should be set to the value of the
argument(s) which follow it.

For example, in a message from controller to target, BSA = 1 would mean ‘enable
the power supply for BUC A.’

The ? code (controller to target) is used as the query operator, and is used to indicate that
the target should return the current value of the parameter defined by the preceding byte.


For example, in a message from controller to target, ‘BSA?’ would mean return the
current state of BUC A power supply.’




A-4