Fluke 8506A Instruction Manual page 243

8505A885G6A-G6
Table 606-1.
Mode
Selection
BC3II
SELECTION SW OFF
SI Current
Loop/RS232
Current
mm
S2
RS232B/RS232C
RS232B
S3
Stop
Bits
1
Bit
S4 Baud
Rate
*
tf
S5 Baud
Rate
«-
*
S8 Baud
Rate
*
*
S7 Baud Rate
*
S8
Parity
Odd
Even
*
Defined
in
Table
606-2
Table 606-2.
Baud
Rate
Selection
COUNT
S4 SB S6 S7
BAUD
RATE
0
OFF OFF OFF OFF
110
1
OFF OFF OFF
ON
150
2
OFF
OFF ON
OFF
300
3
OFF OFF ON ON
2400
4
OFF ON OFF OFF
1200
5
OFF
ON
OFF
ON
1800
6
OFF
ON
ON
OFF
4800
7
OFF
ON
ON
ON
9600
8
ON OFF
OFF
OFF
2400
9
ON
OFF OFF
ON
600
10
ON
OFF ON
OFF
200
11
ON OFF
ON
ON
134.5
12
ON ON OFF OFF
75
13
ON
ON OFF
ON
50
Table 606-3.
Jumper
Arrangements
JUMPER
#1
INSTALLED
JUMPER
INSTALLED
JUMPER
#
INSTALLED
Bit 5
Yes Yes N/A
Bit
6
No
Yes
N/A
Bit 7
Yes
No N/A
Bit
8
No No N/A
Parity
N/A
N/A
Yes
No
Parity
N/A N/A No
606"
19.
The
bit serial
interface
alters
and
transmits data
between
the eight
bit
(byte) parallel
format
used
on
the
instrument bus
and
the
bit serial
format
of the system
bus.
As shown
on
the schematic, data inputs
from
either the
system bus or
the
instrument bus
are latched
into
universal
asynchronous
receiver transmitter
(U
ART)
U9,
which
is
driven
by
a
progammable
clock (U3)
set at
the
selected
baud
rate.
Data
in the
Instrument
Bus
(XDG-I.D7)
is
latched into the
UART
on
DB1
through
DB8
and
output
from
the
UART
to the
instrument bus on
RD1
through
RD8.
Four
separate functions are
decoded
from
the control
lines,
and
the receipt
of any one
generates a
common
acknowledgement
signal
(ACK).
An
interrupt
function can be
generated to notify the instrument
controller the received data
is
available,
allowing polled
or interrupt control of the
interface.
606"20. Functions
606-21.
An
address of ICO, IC4 and IC6
high with the
remaining
lines
low
generates the
STATIN
function. This
generates
ACK
and
enables the
tri-state
transmitters
on
the
ID0-ID3
lines
so that
DA
(received data available
at
RD1-RD8),
OR
(overrun;
i.e.,
a
new
character received
prior to final transmission of the previous character),
RVMT
(transmitter buffer
empty
and,
ready
for
the next
character)
and/ or
FE
(framing
error;
i.e.,
no
stop
bit
with
received character)
can be
placed
on
the data
lines.
606-22.
The DATIN'
function (IC1, IC4,
IC6
only high)
strobes the
RDE
and
RDA
input
to the
UART.
The
UART
is
enabled
to place data
on
the
instrument bus by
RDE
and
to receive another
serial
character
from
the
system bus by
RDA.
606-23.
With
IC2,
IC4 and
ICS
high,
COUT
is
decoded
to reset the
UART
and clock U5-3.
If
ID7
is
high with
COUT,
the interrupt capability
is
disabled
by enabling
the reset at
US-
10.
This
action prevents
an
interrupt signal
to the
instrument
controller
until
removed.
If
ID8
is
low,
the interrupt circuitry
is
enabled.
606-24.
DATOUT
is
decoded from
IC3,
IC4 and IC6
high, to strobe the
DS
input to the
UART.
The
rising
edge
of
DS
initiates serial
transmission of the character
from
SO
onto
the
system
bus.
It
is
available
at
both Jl-2 for
RS-232 and
31-11 for the 20
mA
current
loop, for
the
users selection.
S08~25„ Interrupt
606-26.
When
DA
(received data
available) goes high,
an
interrupt
is
generated
(unless
it
has been
disabled
by
the
COUT
function)
for
a low
at
INT.
The
instrument
606-3