HP 8921A, Руководство программиста

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Chapter 2, Methods For Reading Measurement Results
HP BASIC ‘ON TIMEOUT’ Example Program
Comments for Recommended Routine
Table 6 Comments for Measure Function from ON TIMEOUT
Example Program
Program Line
Number
Comments
50 Send a Selected Device Clear (SDC) to the Test Set to put the HP-IB subsystem
into a known state. This allows the control program to regain programmatic
control of the Test Set if it is in an error state when the program begins to run.
60 Command the Test Set to abort the currently executing measurement cycle. This
will force the Test Set to stop waiting for any measurement results to be available
from measurements which may be in an invalid state when the program begins to
run.
290 Turn event initiated branches off (except ON END, ON ERROR and ON
TIMEOUT) to ensure that the Measure function will not be exited until it is
finished.
300 Set up a timeout for any I/O activity on the HP-IB. This will allow the function to
recover if the bus hangs for any reason.
310 Set the triggering mode to single followed by a trigger immediate command. This
ensures that a new measurement cycle will be started when the TRIG:IMM
command is sent. This sequence, that is: set to single trigger and then send a
trigger command, guarantees that the measurement result returned to the ENTER
statement will accurately reflect the state of the DUT when the TRIG:IMM
command was sent. The ’IMM’ keyword is optional.
320 Send the query command passed to the Measure function to the Test Set.
330 Read the measurement result.
340 Set the trigger mode to repetitive retriggering. Setting the trigger mode to
repetitive will be implementation dependent.
350 Re-enable event initiated branching. If any event initiated branches were logged
while the Measure function was executing they will be executed when system
priority permits.