Common Commands; Scpi Commands - Keithley 2750 User Manual

G-10 IEEE-488 Bus Overview

Common commands

Common commands are commands that are common to all devices on the bus. These com-
mands are designated and defined by the IEEE-488.2 standard.
Generally, these commands are sent as one or more ASCII characters that tell the device to
perform a common operation, such as reset. The IEEE-488 bus treats these commands as
data in that ATN is false when the commands are transmitted.

SCPI commands

SCPI commands are commands that are particular to each device on the bus. These com-
mands are designated by the instrument manufacturer and are based on the instrument
model defined by the Standard Commands for Programmable Instruments (SCPI) Consor-
tium's SCPI standard.
Generally, these commands are sent as one or more ASCII characters that tell the device to
perform a particular operation, such as setting a range or closing a relay. The IEEE-488
bus treats these commands as data in that ATN is false when the commands are
transmitted.
Command codes
Command codes for the various commands that use the data lines are summarized in
Figure
Table
Table G-2
Hexadecimal and decimal command codes
Command
GTL
SDC
GET
LLO
DCL
SPE
SPD
LAG
TAG
SCG
UNL
UNT
G-3. Hexadecimal and the decimal values for the various commands are listed in
G-2.
Hex value Decimal value
01
04
08
11
14
18
19
20-3F
40-5F
60-7F
3F
5F
Model 2750 Multimeter/Switch System User's Manual
1
4
8
17
20
24
25
32-63
64-95
96-127
63
95