National Instruments GPIB-SCSI-A, Руководство пользователя

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Chapter 7 G Mode Functions
© National Instruments Corp. 7-91 GPIB-SCSI-A User Manual
srqen - Enable/Disable Setting of SRQ
Type: GPIB Configuration function
Syntax:
srqen mask<CR>
or
srqen?<CR>
Purpose: Use
srqen
to allow the GPIB-SCSI-A to assert SRQ under
the conditions described in Table 7-2.
Remarks: When the argument
mask
is 0, the GPIB-SCSI-A never
asserts SRQ. When the argument
mask
is > 0, the GPIB-
SCSI-A asserts SRQ under the conditions represented by each
bit in the
mask
. The SRQ
mask
bits are listed in Table 7-2.
Table 7-2. SRQ Mask Bits
Hex Decimal
Bit Value Value Mnemonic Description
0 1 1 - Not used
1 2 2 - Not used
2 4 4 - Not used
3 8 8 DCR
I
ndicates that the data channel is ready
to transfer data to or from the SCSI.
Essentially, this bit indicates whether
or not the selected SCSI Target has
entered the expected Data In or Data
Out phases.
4 10 16 RDY Indicates that the GPIB-SCSI-A is
now in a state where it can
communicate via the Command and
Status Channel.
5 20 32 - Not used
(continues)