Keithley 199 User Manual

IEEE-488 PROGRAMMING
3.8.3 LLO (Local Lockout)
The LLO command is used to lock out operation of the
LOCAL key, thereby completely locking out, fro?t panel
operation of the instrument (recall that the remaining con-
trols are locked out when the instrument is placed in
remote).
To send the LLO command, the controller must perform
the following steps:
1. Set ATN true.
2. Place the LLO command byte on the data bus.
To cancel local lockout and return control to the front
panel, REN must be set false by sending the LOCAL 7
command to the instrument.
Programming example-To verify LLO operation, enter the
following statements:
FEMOTE 726.
LIXRL LOCl;rJUT 7
After the second statement is executed, the LOCAL key
will be locked out.
To cancel LLO, type in the following statement:
When END LINE is pressed, control to the front panel will
be restored.
3.8.4 GTL (Go To Local)
The GTL command is used to take the instrument out of
the remote mode and restore operation of the front panel
keys.
To send GTL, the controller must perform the following
sequence:
1. Set ATN true.
2. Address the Model 199 to listen.
3. Place the GTL command byte on the data lines.
The GTL command will not cancel LLO (local lockout)
since it does not set REN false.
.-..
Programming Example-Place the instrument in the
remote mode with the following statement:
REMCITE 726
Verify that the instrument is in remote.
Send GTL as follows:
Note that the instrument goes into the local m~ode, and
that operation of the front panel keys has now been
restored.
3.8.5 DCL (Device Clear)
The DCL command may be used to clear the Model 199
and return it to its default conditions. Note that the DCL
command is not an addressed command, so a31 in-
struments equipped to implement DCL wiU do so
simultaneously. When the Model 199 receives a DCL com-
&and, it will return to default conditions (see paragraph
3.9.11). %ble 3-7 lists factory default conditions.
Table 3-7. Factory Default Conditions
Mode
Multiplex*
Reading
Function*
Data Format
Self-Test
EOI
SRQ
Filter*
Interval’
Data Store Size’
Range*
Rate*
Trigger
Delay’
Terminator
Zero
Command
Al
BO
E
JO
Ko
MO
E
IO
R4
Sl
T6
wo
zi
Enabled
A/D converter
DC volts
Send prefix with
reading
Clear
Enable EOI and bus
hold-off on X
Disabled
Internal enabled
l75msec (SELECT
OFF)
Coniinuous
3oov
SYzd, line cycle
integration
continuous on ex-
ternal trigger
No delay
CR LF
Disabled
These defaults can be changed. See paragraph 3.9.11.
3-11

Keithley 199 Specifications

General

Brand	Keithley
Model	199
Category	Scanner
Language	English