Keithley 2000 User Manual page 138

4-52 Remote Operation
*WAI — Wait-to-Continue
Description
Two types of device commands exist:
•
•
Use the *WAI command to suspend the execution of subsequent commands until the device
operations of all previous Overlapped commands are finished. The *WAI command is not need-
ed for Sequential commands.
The Model 2000 has three overlapped commands:
•
•
•
Note: See *OPC, *OPC? and *TRG for more information.
The :INITiate commands remove the Model 2000 from the idle state. The device operations
of :INITiate are not considered complete until the Model 2000 returns to idle. By sending the
*WAI command after the :INITiate command, all subsequent commands will not execute until
the Model 2000 goes back into idle.
The *TRG command issues a bus trigger that could be used to provide the arm, scan, and
measure events for the Trigger Model. By sending the *WAI command after the *TRG com-
mand, subsequent commands will not executed until the pointer for the Trigger Model has fin-
ished moving in response to *TRG and has settled at its next state.
Program Fragment
PRINT #1, "output 02; :syst:pres"
PRINT #1, "output 02; :init:cont off;:abort"
PRINT #1, "output 02; :trig:coun 1;sour tim"
PRINT #1, "output 02; :samp:coun 30"
PRINT #1, "output 02;:init; *wai"
PRINT #1, "output 02; :data?"
PRINT #1, "enter 02"
LINE INPUT #2, a$
PRINT a$
Prevent execution of commands until previous commands are
completed
Sequential commands-A command whose operations are allowed to finish before the
next command is executed.
Overlapped commands-A command that allows the execution of subsequent commands
while device operations of the Overlapped command are still in progress.
:INITiate
:INITiate:CONTinuous ON
*TRG
'Select defaults
'Place 2000 in idle
'Program for 30 measurements and
'then stop (idle)
'Start measurements and send *wai
'Query a reading
'Get reading after 2000 goes into
idle
'Read the reading
'Display the reading