HP 8508A - Page 57

BUEUMRPeRSeRB BRB REE RE RBS RP eeeeeeanneaerae@zaun
:
Operation
CeSONEL FOR.
HP-AB
460
1f
BIT(Stat,7)
THEN
470
PRINT
**HP8SO8A
UNLOCKED’
‘
480
REPEAT
490
OUTPUT
Addr;’*STATUS:OPER
:COND?’
*
500
.
ENTER
Addr;Condition
510
UNTIL
BIT(Condition,2)<0
1!
Wait
for
lockup
again
520
PRINT
**HP&508A
LOCKED!’
23
530
OUTPUT
Addr;
’’*CLS’’
!
Clear
ALL
Status
Structures
540 END IF
550 !
560
ENABLE
INTR
7
!
re-enable
SRQ
570
SUBEND
.
Figure
3-23.
SRQ
Enabling
and
Handling
Sending
the
Service
Request
Message
ssage
in
either
local
or
remote
mode.
When
it
is
sending
the
The
Vector
Voltmeter
sends
the
Service
Request
me
ed
by
the
controller
message,
the
front
panel
S
annunciator
lights.
The
message
is
cleared
when
a
serial
poll
is
execut
or
when
a
*CLS
(Clear
Status)
instrument
command
is
received.
Sending
the
Status
Byte
Message
The
Vector
Voltmeter
sends
the
Status
Byte
message
after
receiving
a
Serial
Poll
Enable
(SPE)
bus
command
and
when
addressed
to
talk.
It
complies
with
IEEE488.2,
so
bits
4
and
5
are
defined
as
MAV
and
ESB,
respectively.
The
Vector
Voltmeter
also
makes
use
of
bit
7
as
the
Operation
Status
Register
Summary
Bit
but
all
other
bits
are
unused,
The
bit
pattern
of
the
Status
Byte
is
shown
in
Figure
3-25.
Once
the
Vector
Voltmeter
receives
the
SPE
bus
command,
it
is
no
longer
able
to
alter
the
Status
Byte.
If
a
bit
has
been
enabled
and
that
condition
occurs
after
bit
6
has
been
set,
the
bit
is
stored
in
a
buffer
and
is
read
the
next
time
the
Vector
Voltmeter
receives
the
SPE
bus
command.
The
Status
Byte
and
any
Service
Request
message
pending
will
be
cleared
if
a
*CLS
(Clear
Status)
instrument
command
is
received
by
the
Vector
Voltmeter.
E1089
3-33