The LDC-3700C Series Laser Diode Controller provides both USB and GPIB communications. The command set is the same for both communication protocols. It is, however, recommended to only USB or GPIB to the instrument at any given time. Simultaneous operation of both protocols is not supported. Everything you can do from the front panel can also be done remotely, and in some cases, with more flexibility. For instance, in remote mode, you have access to commands for functions not found on the front panel, such as commands that will increment (INC) and decrement (DEC) the current set point by a pre-defined step value. Also, you may only query the TEC voltage via remote control. The following sections show you the fundamentals of operating your LDC-3700C Laser Diode Controller remotely through the USB or GPIB interface.