Communication Protocol; Overview; Message Body; Mnemonic - Digital Projection Vision 30 Series Communication Protocol Manual

Communication Protocol

This section describes how to use the communication protocol to control projectors remotely.
When the projects are connected to either RS232 or LAN you can control the projectors through this ASCII based protocol.
Note: Some commands will generate OSD feedback. This can be turned off from the projector's menu system or by setting
"OSDC" to value 0 (OSD off) or value 1 (OSD show only warnings).

Overview

The protocol has the following definition:
HEADER SEPARATOR
1 byte 1 byte
Field
Header
Separator
Address
Terminator

Message body

The message body structure is as follows:

MNEMONIC

SEPARATOR]
1 byte 1 byte
Field
Mnemonic
Modifer
VALUES
Separator
Mnemonic
The Mnemonic is 4 bytes key identifier, know as the ASCII command.
Example: POWR, SABS, IVGA

Modifiers

R
A
?
?M
?N
?D
?S
ADDRESS SEPARATOR
1 -3 bytes 1 byte
Description
ASCII character ':'
ASCII character 'space'
1 – 3 bytes address
CR carriage return (0x0D)
MODIFIER SEPARATOR
1 -3 bytes 1 byte
Description
4 bytes key identifier, not case sensitive
Single char symbol
1 – 3 bytes address
ASCII character 'space'
Relative change. Value given will be reletive to the existing value.
Example: :BRIG R10 will increase brightness with 10 steps
Request acknowledges. This modifier is the only
used to read back the result of the command.
Default all commands send acknowledges so this will not be
necessary.
Get current value
Get maximum value
Get minimum value
Get default value
Get default step value
MESSAGE BODY TERMINATOR
N bytes 1 byte
Comment
Required
Optional
Optional
Required
VALUES
N bytes
Comment
Required
Optional
Optional
Optional