Tektronix DM 5010, Инструкция по эксплуатации

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DM 5010 Instrument Interfacing Guide
Notice that the DM 5010 message (what's inside
the quote marks) is the same in all of the above exam­
ples. The rest of each example varies to match the
PRINT statement syntax designed into each controller
as illustrated in Fig. 2. This suggests that once you
understand your controller's output and input state­
ments, it's just a matter of plugging in the DM 5010
commands you need.
4050-Series BASIC
4041 BASIC
HP-85 BASIC
FLUKE 1720A BASIC
HP 9826 BASIC
PRINT @5:“RQS ON”
PRINT #5:“RQS ON”
OUTPUT 705 ; “RQS ON”
PRINT
@5%, “RQS ON”
OUTPUT 705;“ RQS ON”
4603 *5
Fig. 2. A message to a GPIB device is contained with­
in the controller's GPIB output statement. The state­
ment is composed of three parts: the keyword, the
address or logical unit number, and the device-depen­
dent message. AH the statements shown send the
same standard Tektronix Codes & Formats message
(RQS ON) that enables SRQ interrupts. All send the
message to an instrument with primary address 5.
The difference lies in the syntax of the statement re­
quired for a particular controller.
Getting DM 5010 Current Settings
DM 5010 queries or output commands (such as
FUNCT?, MODE?, or SEND) prepare the instrument
for output, but do not start such output. The DM 5010
waits until it sees its talk address to begin sending the
requested data. This is accomplished by the INPUT
statement.
4050-Series:
280 PRINT @16:" FUNC?"
290 INPUT @16:F$
4041:
290 input #16 prompt "FUNC?":fnction$
All instrument settings can be obtained in one mes­
sage. Just dimension a string large enough (300 char­
acters is plenty) and input the settings string.
4050-Series:
330 DIM S $(300)
340 PRINT @16:"SET?"
350 INPUT @16:S$
4041:
330 Dim setting$ to 300
340 Input #16 prompt "SET?”:setting$
You can restore the settings you input from the DM
5010 by sending back the settings string.
4050-Series:
380 PRINT @16:S$
4041:
380 Print #16: setting$
Getting DM 5010 Measurements
Getting measurements from the DM 5010 is even
easier than getting settings data. Sending the DM
5010 talk address, which INPUT does, is enough to
cause the DM 5010 to output a reading. (The DM
5010 responds with a reading if it has not been told by
a query command to respond with some other out­
put.) The DM 5010 sends the reading as ASCII nu­
meric characters, which may be input into a character
string or numeric variable. The variable and its type
are specified after the colon in the INPUT statement.
4050-Series:
430 INPUT @ 16:R
4041:
430 Input #16:reading
If a reading is not available, say the DM 5010 was
set to triggered mode but no reading was triggered,
the INPUT statement causes the DM 5010 to trigger a
reading and output it as soon as it is available. Mean­
while, it holds off further GPIB activity by halting the
handshake. This may be undesirable if the DM 5010 is
set to average many readings before it can output a
response. The SEND command is provided for this
reason. Its use is illustrated in the sample measure­
ment program later in this guide. SEND allows the
program to handle other events or do other process­
ing while many readings are averaged. It also avoids a
timeout, which occurs if the DM 5010 is talked but
cannot supply output within five seconds.
If the program does request a long averaging oper­
ation, does not use SEND, and attempts to INPUT the
reading before it is ready, it can cause the DM 5010 to
time out. If a time out occurs, the DM 5010 does not
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