Knoll hd177 User Manual

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RS232 Terminal Specifications and Commands  
 
To control the projector from an LCD control panel, connect an RS-232 cable to the serial control 
connector on the projector and set your computer’s serial port settings to match this communication 
configuration: 
 
Command format 
All commands consist of 3 alpha characters followed by a request, all enclosed in parentheses. The request 
can be a read request (indicated by a “?”) or a write request (indicated by 1 to 4 ASCII digits). 
A read request format: (AAA?) where 
 
starts the command 
 
AAA  denotes the command 
 
denotes the read request 
 
ends the command 
 
A read command returns 
the range and the current 
setting, for example: 
 
A write request example: (AAA####) where 
 
starts the command 
 
AAA  denotes the command 
 
####  denotes the value to be written 
 
 
(leading zeros not necessary) 
 
ends the command 
Some commands have ranges, while others are absolute. If a number greater than the maximum range is 
received, it is automatically set to the maximum number for that function. If a command is received that is 
not understood, a “?” is 
returned. With absolute 
settings, “0” is off, 1-9999 
is on.  
The one exception is the 
Power command, where 0 
is off and 1 is on.