Fluke 8506A Instruction Manual page 233

85G5A/8506A-05
Table 605-4. Interface Messages
1
ALL
DEVICES
RESPOND
(Universal)
ADDRESSED
DEVICES
ONLY
RESPOND
DEVICE
IN
LOCAL
RESPONDS
AND
GOES
TO REMOTE
NOTE
BINARY OCTAL HEX
i
My
Listen
Address
X
F
T AS A
4
A3 A2
A1
X
X
1
My
Talk
Address
X T
F
AS A4 A3 A2
A1
X X
1
Uniisten
077 3F
X
UNT
Untalk
XTFTTTTT
137
5F
X X
OTA
Other
Talk
Address X
X
X X X
X X
X
X
2
SPE
Serial Poll
Enable
XFFTTFFF
030
18
X X
SPD
Serial Poll
Disable
XFFTTFFT
031
19
X
X
LtO
Local
Lockout
XFFTFFFT
021
11
X X
GTL
Go To
Local
XFFFFFFT
001 01
X
DCL
Device Clear
XFFTFTFF
024
14
X
SDO
Selected Clear
Xppppypp
004 04 X
-
.
Illlf
.
605-25. Resets
605-26.
Power-on
or
software
resets
may
occur.
At
power-on, U8(PB)-10
causes
an
interface reset to
prevent
unwanted
states
in
the interface
logic.
Software
resets,
decoded by U13(PB)-6,
may
occur
as a result
of a
momentary power
interruption,
a front
panel
request, or
a system
request.
@05-27= Control Register
605-28.
The
following
six
"D"
flip-flops
compose
the
control
register:
1.
Interrupt enable
U14(PB)-2 remains
true,
except during
the
power-on
routine.
2.
A
service request
(SRQ)
to the
system
controller
is
initiated
by U14(PB)-13.
3.
The
instrument controller
being ready
for data
(RFD)
is
indicated
by U16(PB)~I.
4.
At
the
last
data byte of
a
message
to
the system
from
the instrument controller,
U11(PB)-13 goes
true.
5.
Data
accepted
(DAC)
is
sent
and
RFD
is
reset
by U16(PB-13.
6.
When
the
instrument
is
a talker,
Ull(PB)-2
is
used
to
generate the data available
(DAV)
signal.
605-29. Status Register
605-30.
The
status register consists
of
U28 and
part of
U31.
The
instrument address
decoded by
U!3(PB)-9
enables a
status
byte
to
be placed
on
the data
bus (IDO-
ID7). This status byte
is
defined as
follows:
1.
IDO: true
from U28-7
when
in the talk
only
mode.
2.
ID1: true
from U28-9 when remote
enable
(REN) from
the
system
controller
is
false,
3.
ID2:
true
from U28-9
when
go
to local
(GTL)
is
true
from
the
message decoder
U5-4.
4.
IDS:
true
from U28-3
for
an interface message.
5.
ID4:
true
from U3I-3
for
an
interface
message.
6.
IDS: true
from U31-5
to
indicate a device
dependent message.
7.
ID6:
true
from U31-7
during the
serial
poll
mode when
the
system
controller
is
requesting
status.
8.
ID7: true
from U31-9
when
the
system
controller
is
requesting data
from
the instrument.
605-5