X-Execute - Keithley 486 Instruction Manual

SECTION 4
IEEE-488 Reference
4.2.22 x -
Execute
Purpose To direct the instrument to execute device-dependent commands received since the last X.
Format
<commands X
Parameters
None
Description
The execute command is implemented by sending an ASCII 'X" over the bus. Its purpose is to
direct the instrument to execute other device-dependent commands. Usually the execute char-
acterO()isthelastbyteintheco
mmand string (a number of commands may be grouped to-
gether into one string). However, there may certain cases when it is desirable to send a com-
mand string at one time, and then send the execute character later on.
Programming
Notes
1. Commands or command strings sent without theX character are not executed at that time,
but they are stored in an internal command buffer for later execution. When the X is finally
transmitted, the stored commands are executed, assuming that all comman ds in the previ-
ous string were valid.
2. Commands in an X-terminated string are executed in the following order:
A. All commands, except H and L (default options), are executed simultaneously.
B. A default option of tbeL command is executed next. A restore operation (LO or L2) will
return the instrument to a default state after executing the other commands. Thus, in
effect, the other commands in the string are nullified. The save option CLl) saves the
instrument states after the other commands (except H) are executed.
C. The H command is the last co mmand in the string to be executed.
3. To force a particular co mmand sequence, include the X character after each command in
the command string.
4. The X character can also be used to trigger, as described in paragraph 4.2.18.
Programming
Examples
OLTPTJT
722;
'TIX"
OUTPUT 722; 'lJOO1X'
OUTPUT 722; "H3XH7x"
OUTPUT 722; 'NOPI"
OUTPUT 722; 'Y
! Execute single command
! Execute multiple command string.
! Force command sequence to enable (or disable)
autorange.
! Send string without executing.
! Execute previous command string.
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