HP 8921A, Руководство программиста

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Chapter 5, Advanced Operations
Status Reporting
Output Queue Group
The Output Queue Group is a specific implementation of the status queue model
described in
"Status Queue Model" on page 254
. The Output Queue queue type is
defined by the IEEE 488.2-1987 Standard to be a first in, first out (FIFO) queue.
The Output Queue Group includes a FIFO queue and a Message Available
(MAV) Summary Message. Refer to the
"Status Reporting Structure Overview"
on page 244
for an overview of status queue operation.
Figure 10
shows the
structure of the Output Queue Group.
Figure 10 Output Queue Group
Last Data Byte Entered
Next Data Byte Entered
First Data Byte Entered
Last Data Byte
to be Read
First Data Byte
to be Read
Message Available ( MAV )
(to bit 4 of Status Byte Register)
Queue Empty = "0"
Queue Not - Empty = "1"
Output Queue