Description of the Features The SD385 IEEE-488 interface (or GPIB) is a standard feature included on all SD385s. The performance of the GPIB is not affected by the installation of options. This implementation of the IEEE-488 is a standard talker-listener with Service Request and Serial Poll capability, and the ability to be configured in a "talk-only" mode (primarily for digital plotting without the expense of a controller). This feature gives the user with an IEEE capable computer the ability to remotely control the instrument and read analysis results from it for processing. Users with IEEE interface HP-GL plotters can produce quality hard copy using the IEEE and the SD385's built-in plotter capability. The inclusion of the Service Request (SRQ) capability allows the instrument to request attention from the computer upon events the computer identifies as being important. Serial Poll capability allows a computer to identify the requesting device and provides some information about the cause of the SRQ.