National Instruments GPIB-SCSI-A, Руководство пользователя

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G Mode Functions Chapter 7
GPIB-SCSI-A User Manual 7-28 © National Instruments Corp.
getscsi - Arbitrate for the SCSI Bus
Type: SCSI Function
Syntax:
getscsi
<CR>
Purpose: Use
getscsi
to arbitrate for the SCSI bus if the high level
commands performed by the GPIB-SCSI-A do not meet your
needs and you need to perform low level commands with your
device.
Remarks: This is the first command that you need to use in your low
level command pattern if the high-level commands offered by
the GPIB-SCSI-A do not work with your SCSI device. This
command performs the Arbitration phase for the SCSI bus.
If the SCSI bus is currently being used by another Initiator,
this command aborts with an EARB error indication.
If there is anything following
getscsi
, the command aborts
and returns an EARG indication.
If this command completes and there is no error indicated, you
can proceed with the low level command sequence as the
GPIB-SCSI-A now has control of the SCSI bus.
See Also: Appendix D, Operation of the SCSI.
Example:
ibwrt (gpibscsia, "getscsi\n", 8);
/* Arbitrate for the SCSI bus. */