HP 34401A, Руководство пользователя

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C a u t i o n
If you send two query commands without reading the response from the
first, and then attempt to read the second response, you may receive some
data from the first response followed by the complete second response.
To avoid this, do not send a query command without reading the
response. When you cannot avoid this situation, send a device clear
before sending the second query command.
Using the INITiate and FETCh? Commands
The
INITiate
and
FETCh?
commands provide the lowest level of
control (with the most flexibility) of measurement triggering and
reading retrieval. Use the
INITiate
command after you have
configured the multimeter for the measurement. This changes the state
of the triggering system from the “idle” state to the “wait-for-trigger”
state. Measurements will begin when the specified trigger conditions
are satisfied after the
INITiate
command is received. The readings are
placed in the multimeter’s internal memory (up to 512 readings can be
stored). Readings
are stored in memory until you are able to retrieve them.
Use the
FETCh?
command to transfer the readings from the
multimeter’s internal memory to the multimeter’s output buffer where
you can read them into your bus controller.
MEASure?
Example The following program segment shows how to use the
MEASure?
command to make a measurement. This example configures the
multimeter for dc voltage measurements, automatically places the
multimeter in the “wait-for-trigger” state, internally triggers the
multimeter to take one reading, and then sends the reading to the
output buffer.
MEAS:VOLT:DC? 10,0.003
bus enter statement
This is the simplest way to take a reading. However, you do not have
any flexibility with
MEASure?
to set the trigger count, sample count,
trigger delay, etc. All measurement parameters except function, range,
and resolution are preset for you automatically (
see the table on page 112 ).
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Chapter 4 Remote Interface Reference
Simplified Programming Overview
115