Quantum Composers Motorized Attenuator - Manual (Page 6)

Parameters (optional field) Some commands may have parameters which
immediately follow the command string. Multiple parameters are
separated by commas.
Terminator ASCII carriage return character (decimal value 13). The receiving
device does not process any commands until the terminator is
received.
Device Addresses
Address Device
A0 266nm attenuator module
A1 355nm attenuator module
A2 532nm attenuator module
A3 1064nm attenuator module
Command Types
There are two types of commands -- those that set a value or initiate an actions (control
commands), and those that request information (query commands). Each device must
respond in the proper manner to each type of command.
Control Commands
A device must always parse a control command and return a response immediately.
• If the command is a recognized command and the parameter is valid, then the
device returns an "OK". ( = ASCII carriage return, decimal value 13).
• If the command is not recognized by the device, then it responds with "?1
• If the command is recognized, but the parameter value is missing or invalid, then the
device responds with a "?2".
• If the command is recognized, but the parameter is out of range, then the device
responds with a “?3”.
If a control command is received while the device is in the midst of executing a previous
command, and the commands are mutually exclusive (cannot be executed in parallel),
then the previous command is aborted and the new one executed. It is up to the host
controller (the PC) to poll the device and make sure the previous command is finished, if
that is the needed.
Query Commands
Query commands return a value to the PC as soon as the command is parsed and
executed. The value returned will depend on the command. The response is always