Basic Message Structure - Christie Mirage SST Technical Reference

Generally, most commands include 0 or 1 data fields or parameters. Where applicable, a message may
expand to include additional parameters of related details.
The smallest step size for any parameter is always 1. For some controls (such as Size) the value
displayed on the screen has a decimal point (for example, 0.200 to 4.000). In this case, the values
used for the serial communications is an integer value (for example, 200 to 4000), not the decimal
value seen on the screen.

Basic message structure

Understand the component fields that comprise a standard ASCII message.
Components
Start and end of message
Prefix characters (optional) To acknowledge that Mirage SST has responded, and/or maximize message integrity,
Function code
+Subcode
Request/reply symbols
Data
Mirage SST Technical Reference–Serial Commands
020-103005-03 Rev. 1 (01-2021)
Copyright © 2021 Christie Digital Systems USA, Inc. All rights reserved.
Description
Every message begins with the left bracket character and ends with the right bracket
character.
If the start character is received before an end character of the previous message,
the partial (previous) message is discarded.
insert one or two special characters before the three-character function code:
• $ (Simple Acknowledgment)—Causes a dollar sign ($) character to be sent from
Mirage SST when it has finished processing the message.
• # (Full Acknowledgment)—Causes an echo of the message as a reply to be sent
from Mirage SST when it has finished processing the message.
• & (Checksum)—Allows a checksum to be put as the last parameter in the
message for verification at Mirage SST.
The Mirage SST function you want to work with, such as channel selection or
gamma, is represented by a three-character ASCII code (A-Z, upper or lower case).
This function code appears immediately after the leading bracket that starts the
message. In messages sent to Mirage SST that do not have a subcode, a space
between the function code and the first parameter (or special character) is optional.
The Mirage SST function you want to work with may have one or more subcodes that
allow you to select a specific source, image, channel or subfunction.
The subcode is represented by a four-character ASCII code (A-Z, upper or lower
case, and 0-9). This subcode appears immediately after the function code, with a
plus sign (+) character to separate the code and subcode. If there is no subcode, the
plus sign (+) is also omitted. In messages sent to Mirage SST that have a subcode, a
space between the subcode and the first parameter (or special character) is optional.
If the controller is requesting information from Mirage SST, a question mark (?)
appears directly after the function code. If Mirage SST is replying, an exclamation
mark (!) appears directly after the function code. For set messages to Mirage SST,
neither of these characters appear—data directly follows the code and subcode.
A request for information is represented by a question mark (?) that appears directly
after the function code. A reply is represented by an exclamation mark (!) that
appears directly after the function code or subcode, if one is provided. The first
parameter located after the exclamation mark (!) reply character cannot have a
space, for example (PWR!000).
The value for a given Mirage SST state, such as on or off, appears in ASCII-decimal
format directly after the request/reply symbol. You can add an optional space after
Communicating with Mirage SST
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