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4-13
COMMAND
OPERATIONS
The following example in HP Basic
sets the set point to 123.4 K, the
The DRC-93C1s Output Requests for
gain to 45, the reset (integral) to
Data Statements are summarized in
30, the rate (derivative) to 25,
Table 4-5.
the heater range to 10-1 and the
output statement sent to be W3.
The DRC-93C
will
always respond
when asked to talk with the last
command sent to it, i.e.
,
if WO is
sent once then the 93C will always
output the WO information whenever
it is asked to talk as long as it
has not
received another output
data statement.
If the user were to monitor the
4.14.1
T h e
"WS",
"WC"
and
"WP"
Data
IEEE-488 Bus when the computer sent
S t r i n g s
its command string over the Bus,
the following IEEE-488 Format would
These three commands are subsets of
be observed.
the
"WO"
command: the "WS" command
giving the Sample Sensor reading,
?
L
,
S123.4P45130D25R4W3(CR) (LF)
the "WC" command the control sensor
reading
while
the
"WP"
command
4-14
OUTPUT
DATA
STATEMENTS
The Universal Unlisten Command
(?)
results in the set point value.
is
sent
so
that
no
other
instruments
on
the
Bus
will
4 . 1 4 . 2
The
"WO"
Data
S t r i n g
eavesdrop on the
Bus
and assume
that the data being sent is for
The following example in HP Basic
their attention.
The DRC-93C1s
illustrate the commands associated
Talk
Address
(L)
is
sent
to
with obtaining output data from the
unaddress
any
existing
TALKER.
DRC-93C.
The addition of the MO
Note that the BUS CONTROLLER could
command returns the instrument to
have designated another instrument
front panel control where it stays
as the TALKER.
Therefore, to keep
even when data is requested from
the format consistent, it must send
a Talk Address even when the DRC-
10
DIM
A$ [19]
93C is going to be that TALKER.
20
OUTPUT
712; "WOMO"
The Listen Address
(,)
must be sent
30
ENTER
712; A$
to tell which instrument on the Bus
The following information is sent
is to
receive the Data
String.
across the bus
in the IEEE-488
Note that [TERM1] [TERM2] have been
format as a result of the above
indicated to be CR LF (carriage
software commands.
return, line feed)
;
these are the
Request sent:
correct
terminators
for
the
HP
?
U
,
W
0
M
0
(CR)(LF)
computer example.
Data returned:
Note that the string "P45130P40"
would result in a gain of 40 and an
integral value of 30, i.e.,
only
the last value sent over the bus
for that command will be entered
after the appropriate terminators
have been sent over the bus.
The data above indicates that the
the 93C by the HP computer.
4-28
COPYRIGHT 3/88 LSCI
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