IEEE-488 Reference
3-2
A DDC language is also available for IEEE-488 bus opera-
tion. In this mode, device-dependent commands (DDCs) are
used instead of SCPI and common commands. This mode is
used when you want to use the Model 6517A as a “drop-in”
replacement for the Model 617. This allows an existing pro-
gram written for the Model 617 to be used by the Model
6517A without having to make any code modifications.
RS-232 serial port
The Model 6517A has a serial port that can be used as an al-
ternative 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 inter-
face, such as a notebook computer.
3.2
Connections
The following information shows how to make connections
using the IEEE-488 bus or the RS-232 serial port.
3.2.1 IEEE-488 bus connections
The Model 6517A can be connected to the IEEE-488 bus
through a cable equipped with standard IEEE-488 connec-
tors, an example is shown in Figure 3-1. The connector can
be stacked to allow a number parallel connections to one in-
strument. Two screws are located on each connector to en-
sure that connections remain secure. Current standards call
for metric threads, which are identified with dark colored
screws. Earlier versions had different screws, which were sil-
ver colored. Do not attempt to use these type of connectors
on the instrument, which is designed for metric threads.
A typical connecting scheme for a multi-unit test system is
shown in Figure 3-2. Although any number of connectors
could theoretically be stacked on one instrument, it is recom-
mended that you stack no more than three connectors on any
one unit to avoid possible mechanical damage.
NOTE
In order to minimize interference caused
by electromagnetic radiation, it is recom-
mended that only shielded IEEE-488 ca-
bles be used. The Models 7007-1 and
7007-2 shielded IEEE-488 cables are
available from Keithley.
Connect the Model 6517A to the IEEE-488 bus as follows:
1. Line up the cable connector with the connector located
on the rear panel. The connector is designed so that it
will fit only one way. Figure 3-3 shows the location of
the IEEE-488 connector on the instrument.
Figure 3-1
IEEE-488 connector
Figure 3-2
IEEE-488 connections
Instrument
Controller
Instrument
Instrument
RNING:
NO INTERNAL OPERATOR SERVICABLE PARTS,SERVICE BY QUALIFIED PERSONNEL ONLY.
RNING:
NO INTERNAL OPERATOR SERVICABLE PARTS,SERVICE BY QUALIFIED PERSONNEL ONLY.
N:
FOR CONTINUED PROTECTION AGAINST FIRE HAZARD,REPLACE FUSE WITH SAME TYPE AND RATING.
N:
FOR CONTINUED PROTECTION AGAINST FIRE HAZARD,REPLACE FUSE WITH SAME TYPE AND RATING.
LINE RATING
50-60HZ
50VA MAX
AC ONLY
LINE FUSE
SLOWBLOW
1/2A 90-125V
1/4A 180-250V
IEEE-488
(CHANGE IEEE ADDRESS
WITH FRONT PANEL MENU)
DIGITAL
I/O
TRIG LINK
115V
Figure 3-3
IEEE-488 connector location
