Keysight N777xC Series Tunable Laser Family Programming Guide 15
Introduction to Programming 1
 
Slot and Channel Numbers
Each module is identified by a slot number and a channel number. For 
commands that require you to specify a channel, the slot number is 
represented by [n] in a command and the channel number is represented 
by [m].
The slot number represents the module’s position in the mainframe. The 
slot number for N777xC is always 0. 
Channel numbers are not used for N777xC.