Tektronix FG 5010 User Manual

C
C
C
C
c
(
П
(
A
n
П
C
C
C
ก
curs
,
the
instrument cannot
finish
executing
the
message
because
it is
waiting for the
controller
to read the
data it has
generated ; but the controller cannot read the data because
it is waiting to finish sending its message . Because the in
strument Input Buffer is full and it is holding off the rest of
the
controllers
message with
NRFD
, the
system
is hung
up
with the
controller
and
instrument
waiting
for each
other .
When the
instrument
detects this
condition , it
generates
an
error , asserts SRQ and delets the data in the Output Buffer .
This action allows the controller to transmit the rest of the
message , and informs the controller that the message was
executed and that the output was deleted .
A TM 5000 instrument can be made a talker without hav
ing received a message that specifies the output . In this
case , an acquisition instrument ( a counter or a multimeter )
returns a measurement if one is ready . If no measurement is
ready , it returns a single byte message with all bits equal to
1
( with
message terminator
) . Non -
acquisition TM 5000
in
struments
will
return
only
this
message
.
Instrument Response to IEEE - 488 Interface
Messages
Interface
messages
and the
effects of those
messages
on the instrument interface functions are defined in IEEE
Standard 488-1978 . Abbreviations from the standard are
used in this discussion , which describes the effects of inter
face messages on instrument operation .
UNL
-
Unlisten
(
WBYTE @ 63 :)
UNT
-
Untalk (
WBYTE @ 95
:)
When the UNL command is received , the instrument lis
tener function goes to its idle state ( unaddressed ) . In the idle
state , the instrument will not accept instrument commands
from the IEEE
-488 bus .
The talker function goes to its idle state when the instru
ment receives the UNT command . In this state , the instru
ment cannot supply output data via the bus .
The ADDRESSED indicator is off when both the talker
and listener functions are idle . If the instrument is either talk
addressed or listen - addressed , the indicator is on .
IFC
Interface
Clear (
Bus pin 9 )
This uniline message has the same effect as both the
UNT and UNL messages . The front panel ADDRESSED in
dicator
is off .
DCL Device
Clear (
WBYTE @ 20 :)
The Device Clear message reinitializes communication
between
the
instrument and
controller
. In
response
to
DCL ,
@
Programming - FG 5010
the
instrument
clears any
input and
output
messages and
any unexecuted settings in the Pending Settings Buffer .
Also
cleared are any errors
or events
waiting
to be
reported
,
except the
power - on event
. If the SRQ
line is
asserted for
any reason other than power - on when DCL is received ,
SRQ is unasserted .
SDC
Selected
Device Clear (
WBYTE @ A , 4 :)
This message performs the same function as DCL ; how
ever , only instruments that are addressed respond to SDC .
GET - Group Execute Trigger ( WBYTE @ A , 8 :)
The instrument responds to < GET > only if it is listen
addressed and the instrument device trigger function has
been enabled by the Device Trigger command ( DT ) . The
< GET > message is ignored and an SRQ generated if the
DT function is disabled ( DT OFF ) , the instrument is in the
local state , or if a message is being processed when
< GET > is received .
SPE - Serial
Poll Enable (
WBYTE
@ 24 :)
The SPE message enables the instrument to supply out
put serial poll status bytes when it is talk addressed .
SPD - Serial
Poll
Disable (
WBYTE
@
25 :)
The
SPD
message
switches the
instrument back
to its
normal operation of sending the data from the Output
Buffer .
MLA - My Listen Address ( WBYTE @A :)
MTA - My Talk
Address
(
WBYTE @B :)
The primary listen and talk addresses are established by
the instrument IEEE - 488 bus address ( set by switches that
are accessible from the back of the FG 5010 when it is re
moved from the Power Module ) . The current setting of the
bus address is displayed on the front panel when the INST
ID button is pressed . When the instrument is addressed to
talk or listen , the front panel ADDRESSED indicator is
lighted
. ( A
bus
address +32 ; B bus
address
+64
.
)
=
LLO - Local
Lockout
(
WBYTE
@ 17 :)
In
response
to LLO
, the
instrument
changes
to a
lockout
state from LOCS to LWLS or from REMS to RWLS .
REN -
Remote
Enable
(
GPIB pin 17 )
If REN is true , the instrument may change to a remote
state ( from LOCS to REMS if the internal message return
to - local ( rt / ) is false , or from LWLS to RWLS ) when its listen
address is received . REN false causes a transition from any
3-29

Tektronix FG 5010 Specifications

General

Brand	Tektronix
Model	FG 5010
Category	Portable Generator
Language	English