In this section:
Introduction ............................................................................ 11-1
Connections ........................................................................... 11-1
Selecting interface parameters ............................................... 11-4
General bus commands ......................................................... 11-7
IEEE-488 front panel operation .............................................. 11-9
Programming syntax ............................................................ 11-10
IEEE-488 trigger model ........................................................ 11-16
RS-232 serial interface ......................................................... 11-20
Introduction
The IEEE-488 is an instrumentation data bus with hardware and programming standards originally
adopted by the Institute of Electrical and Electronic Engineers (IEEE) in 1975 and given the IEEE-488
designation. In 1978 and 1987, the standards were upgraded to IEEE-488-1978 and IEEE-488.1-
1987, respectively. The Keithley Instruments Model 6517B Electrometer conforms to these standards.
Standards
The Model 6517B conforms to the IEEE-488.2-1987 standard and the SCPI 1996 (Standard
Commands for Programmable Instruments) standard. IEEE-488.2 defines a syntax for sending data
to and from instruments, how an instrument interprets this data, what registers should exist to record
the state of the instrument, and a group of common commands. The SCPI standard defines a
command language protocol. It goes one step farther than IEEE-488.2 and defines a standard set of
commands to control every programmable aspect of an instrument.
RS-232 serial port
The Model 6517B has a serial port that can be used as an alternative to the parallel IEEE-488 bus. All
commands, except DDCs, can be used over this serial port. The serial port is based on the electrical
and mechanical characteristics of the RS-232-C standard. Typically, the serial port is used with a
controller that cannot accommodate an IEEE-488 bus interface, such as a notebook computer.
Connections
The following information shows how to make connections using the IEEE-488 bus or the RS-232
serial port.
Section 11
Remote operations