Download AQ7275 Communication Interface - Electro

5.5
Output Queue and Error Queue
Overview of the Output Queue
The output queue is provided to store responsemessages to queries. For example, when
the :WAVeform:SEND? query is sent to request output of the acquired waveform, the
response data will be stored in the output queue until it is read out.The example below
shows that data is stored recordby record in the output queue, and is read out oldestitem
first, newest item last.
The output queue is emptied in the following cases (in addition to whenread-out is
performed).
•When a new message is received from thecontroller
•When dead lock occurs (page 4-2)
•When a device clear command (DCL or SDC) isreceived
•When power is turned ON again
The output queue cannot be emptied using the *CLS command. To see whether the
output queue is emptyor not, check bit 4 (MAV) of the status byte.
D1
D2
D1
D2
D1
Overview of the Error Queue
The error queue stores the error No. and message when an error occurs. For example,
if the controller sends an incorrect program message, the number,“113, “Undefined
header”,” and the error message are stored in the error queue, when the error is
displayed.The contents of the error queue can be read using the:STATus:ERRor? query.
As with the output queue,messages are read oldest first, newest last (refer to theprevious
page).If the error queue becomes full, the final message willbe replaced by message “350,
“Queue overflow”.”
The error queue is emptied in the following cases (inaddition to when read-out is
performed).
•When the *CLS command is received
•When power is turned ON again
To see whether the error queue is empty or not, checkbit 2 (EAV) of the status byte.
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IM 735020-17E