Tektronix 494AP Water Dispenser User Manual


 
Performance
Check
procedure
-
4g4A/4g4Ap
Service
Vol.
I
Lines 9000-10000:
Group
Execute
Trigger
test.
Checks
that a
GET message
does cause
the
Spectrum
Analyzer
to abort
the
present
sweep
and
re-arm
the
trigger, causing
a
sweep
to
start
and
end,
sending
out
an
End-of-Sweep
SRe.
Thus,
the
SRe line
and
GET
m€ssage
are
verified.
Lines 10000-11000:
Selected
Device
Clear
Test.
This
test verifies
that an
SDC message
resets
the
Spec-
trum Analyzer's
GplB
output
buffer clearing
out it's
lD?
response.
Lines 11000-12000:
Device
ctear
test.
This
test is
identical
to
the
selected
device
clear
test,
except
the
universal command
DCL
is
used
instead.
Lines 12000-13000:
Addressed
as tistener,
tatker
test. This
t€st checks
that
the microprocessor
correcily
recognizEs
that
the
GPIA chip
has
been
addressed
to
listen
or talk,
and
sends
the
appropriate
character
to
the ert readout (L
or
T).
Lines 13000-14000:
Seriat
poil
test.
This
checks
correct
operation
of
the
serial
poll
enable (spE)
and
serial
poll
disable (SPD)
interface
messages.
The
status
byte
is
read,
and
if anything
other
than
ordinary
operation is
indicated,
the instrument
tails
the
test.
Lines
14000-15000:
GptB rear
panet
switch
test. Atl
five
primary
address
switch€s
are
checked
for
corr€ct
operation.
Three
subroutines
are
called
in
the
process
of
testing
one
address
switch.
The
first
two send
a for-
matted
rnessage
to the
4050
display,
and
the
third
per-
forms
the
address
switch
test.
Lines
1500G16000:
Line
feed
or
EOt switch
test.
Checks
for
correct
selectlon
of
line
feed
as
a
termina_
tion when selected
by
this switch
by
sending
an
lD?
ter_
minaled only
by a
line
feed.
Lines
16000-17000:
Talk-only
mode
t€st.
When
selected,
this
mode
should
cause
the
instrument
to
send a
SET? response
and
(optionally)
a
CURVE?
response whenever
the
RESET-TO-LOCAL
button
is
pressed.
The
string
received
from
the instrument
is
thus
examined
for
existence of a
portion
of
the correct'
SET?
response
after
the
RESET-TO-LOCAL
button
is
pressed.
Lines 17000-18000:
Listen-only
mod€
test. When
selected,
this
mode
will
cause
ths instrum€nt
to
respond to any message
on
the bus, since
it
is
always
addressed
to listen. The command
REF
0
is sent
to
the
bus
without addressing
the
instrument,
then the
listen-
only
mode is
deselected
and
the instrument interro-
gated
to see if it
did respond
to the REF
command
while
in
the
listen-only
mode.
Lines 18000-'19000:
Interface clean
(and
Remote
Enable) test. This
IFC line
on
the
GPIB will
unaddress
the
instrument's
interface. This is
verified
by
noting
that
the L
is
not
present
in
the
crt
readout,
indicating
that
the
IFC
line
worked;
also the REN line will
be
unasserted
when
the
end statement is
executed
(except
for
some
early
4052 and 4054's).
Thus, a front
panel
in
the local
mode indicates
that the
REN
line was
success-
fully
unasserted.
(Evidence
it
was asserted
is that
the
instrument
was able
to
execut€ commands
sent
to
it
by
previous
tests.)
Lines 19000-end:
Utility
routines.
Rear
panel
inter-
face switch
test text routine
puts
headers
on the inter-
face
switch
test display.
The rear
panel
test
text rou-
tine
tells the
operator
what to
do
after changing
the
address switches.
Test
address
switch
acquires an lD?
response from
the
instrum€nt on its
new address during
the address switch
test.
The
SRQ
handler
will handle
SRQ's
that
occur,
although
none would
be
expected,
except the
power-up
SRO.
(fhe
end of
sweep
SRQ
during the GET
test is
handled
by
anoth€r
SRQ
handler.) Delay
Generator
generates
delays
lor other
tests.
The
Failure Decision Handler
allows
the
program
to be
restarted
with
the
user-definable
keys if
any
test
fails.
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I
1
GOTO s000
4
B2-1
5 RETURN
20 B2-5
21
RETURN
5OOO
REM
"'49XP
GPIB
VERIFICATION
PROGRAM
'-'
5030 tNlT
5O4O
ON SRQ THEN
19280
5050
DrM V$(400),w$(400)
506017-0
5O7O PAGE
5080
pRtNT'J.JJENTER
49Xp'S
pRlMARy
ADDRESS
(DEFAULT:
1)
";
5O9O INPUT T$
5100 tF TS<>" THEN
5130
5110 A1-1
s120
GO
TO
5180
4-40