Controller Programming; Front Panel Aspects Of Ieee-488 Operation; Error And Status Messages; Ieee-488 Status Indicators - Keithley 2001 Operator's Manual

IEEE-488 Reference
5. To retain the displayed address, press EXIT three times
to return the instrument to the measurement display
state.
6. To change the primary address, use the
and the  and keys to display the new address val-
ue (0 to 30). The
tion and the  and keys increment and decrement
the selected digit.
7. With the desired address value displayed, press ENTER.
The address will be stored in non-volatile memory. That
is, it will not be lost when the instrument is turned off.
8. Press EXIT two times to return to the measurement dis-
play state.
Each device on the bus must have a unique
primary address. Failure to observe this
precaution will probably result in erratic
bus operation.
4.4

Controller programming

The programming instructions covered in this section use ex-
amples written with Hewlett-Packard BASIC version 4.0.
This language was chosen because of its versatility in con-
trolling the IEEE-488 bus. This section covers those state-
ments that are essential to Model 2001 operation.
Controller programming information for
using the IBM PC interface through the
Capital Equipment Corporation (CEC),
I/O Tech, and National IEEE-488 interfac-
es is located in the Appendix.
A partial list of HP BASIC 4.0 statements is shown in q~ÄäÉ
QJO. The statements have a one or three digit argument that
must be specified. The first digit is the interface select code,
which is set to 7 at the factory. The last two digits of those
statements requiring a 3-digit argument specify the primary
address.
Those statements with a 3-digit argument show a primary ad-
dress of 16 (the factory set primary address). For a different
address, you would, of course, change the last two digits to
the required value. For example, to send a GTL command to
a device using a primary address of 17, the following state-
ment would be used: LOCAL 717.
Some of the statements have two forms; the exact configura-
tion depends on the command to be sent over the bus. For ex-
4-4
and
and keys control cursor posi-
ample, CLEAR 7 sends a DCL command, while CLEAR
716 sends the SDC command to a device with a primary ad-
dress of 16.
keys
q~ÄäÉ=QJO
HP BASIC 4.0 IEEE-488 statements
Transmit string to device 16.
Obtain string from device 16.
Send GTL to device 16.
Send SDC to device 16.
Send DCL to all devices.
Send remote enable.
Cancel remote enable.
Serial poll device 16.
Send local lockout.
Send GET to device 16.
Send IFC.
4.5 Front panel aspects of
IEEE-488 operation
The following paragraphs discuss aspects of the front panel
that are part of IEEE-488 operation, including messages, sta-
tus indicators, and the LOCAL key.
4.5.1

Error and status messages

Table 3-4 summarizes the error and status messages associ-
ated with IEEE-488 programming. Note that the instrument
may be programmed to generate an SRQ, and command que-
ries can be performed to check for specific error conditions.
4.5.2

IEEE-488 status indicators

The REM (remote), TALK (talk), LSTN (listen), and SRQ
(service request) annunciators show the present IEEE-488
status of the instrument. Each of these indicators is briefly
described below.
As the name implies, this indicator shows when the
instrument is in the remote state. Note that REM does not
necessarily indicate the state of the REN line, as the instru-
ment must be addressed to listen with REN true before the
REM indicator turns on. When the instrument is in remote,
all front panel keys except for the LOCAL key are locked
out. When REM is turned off, the instrument is in the local
state, and front panel operation is restored.
OUTPUT 716;A$
ENTER 716;A$
LOCAL 716
CLEAR 716
CLEAR 7
REMOTE 7
LOCAL 7
SPOLL (716)
LOCAL LOCKOUT 7
TRIGGER 716
ABORT 7
2001-900-01 Rev. K / August 2010