Keithley 237

Programming
Notes
Programming
Examples
SECTION3
IEEE-488
Reference
1.
Set
the bias
value
before
programming
a
sweep
so
the
desired
bias
is
in
effect
when
the
create/append
sweep
(Q)
command
is executed.
The
B
command
should
pre-
cede
or
reside
in
the
same
command
string
as
the
Q
command,
but
not
in
a separate
command
string
after
the
Q
command.
2.
If
autoranging
is
not
used
for
either
the
bias
range
or
sweep
range,
they
should
be
set
to
the
same
fixed
range
to
prevent
range
changes
during
a sweep. Range changes
affect
sweep
timing
and,
since
the
output
level is
momentarily
set
to zero
during
a
range
change,
could
have
an
undesirable
affect
on
the
test
in
progress.
3.
In
autorange,
the
bias
range
is
adjusted
for
the
highest
on-scale
sourcing
possible.
4.
If
the
bias
range
is
not
specified,
the
instrument
will
try
to
place
the
new
bias
level
on
the
present
range. This
could
result
in
a
VALUE
OUT
OF
RANGE
warning.
There-
fore,
it
is
good
practice to
always
specify a
bias
range
when
setting
the
bias level.
5.
Use
the
de
delay
to
compensate
for
any
settling
time
required
by
the
external circuit
connected
to
the
source-measure unit.
6.
Depending
on
your
controller
and
program,
a
bus
timeout
may
occur
during
a long
de
delay.
If
you
trigger a
reading
and
ask
for
it
right
away,
the
bus
is
held
off until the
measurement
is available, possibly
causing
a timeout.
7.
If
time
stamping
is desired,
use
a fixed level
sweep
instead
of
de
operation
(see
the
QO
command
in
paragraph
3.6.15).
8.
Only
terminator
characters are
sent
if
de
data
is
requested
with
the
G
command
while
the
instrument
is
in
the
sweep
function (see
paragraph
3.6.6).
9.
Error
and
warning
conditions for
the
B
command
are
described
in
the
U1
error
status
word
and
U9
warning
status
word
(see
paragraph
3.6.19).
10
20
30
40
10
20
30
REMOTE 716
OUTPUT 716;"FO,lX"
OUTPUT
716;"B5,2,0X"
OUTPUT 716;"Q4,2,8,2,2,100,100X"
OUTPUT
716;"FO,OX"
OUTPUT 716;"B5,2,500X"
OUTPUT 716;"HOX"
!
Source
V,
sweep
! Set
bias
of
5V,
11
V,
or
15V
range
!
Linear
stair
pulsed
sweep,
2-8V,
11
V,
or
15V
range,
IOOmsec
! Source
V,
de
!
5V
bias,
11
V,
or
15V
range,
500msec
delay
! Trigger
output
3-21