National Instruments GPIB-SCSI-A, Руководство пользователя

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Status and Message Information Appendix B
GPIB-SCSI-A User Manual B-2 © National Instruments Corp.
TIMO 16384
The TIMO bit indicates a timeout. The TIMO bit is set in
the status word following a call to
wait
, if the TIMO bit
of the wait mask parameter is also set and if the wait has
exceeded the time limit value that is set by the
tmo
call.
The TIMO bit is also set following a call to any of the I/O
functions (for example,
rd
,
wrt
,
brd
,
bwrt
, and
cmd
),
if a timeout occurs during a call. The TIMO bit is cleared
in the status word in all other circumstances.
END 8192
The END bit indicates if the END or EOS message has
been received. The END bit is set in the status word
following a
rd
or
brd
function if the END or EOS
message was detected during the read. While the
GPIB-SCSI-A is performing a shadow handshake as a
result of the
gts
function, any other function call may
return a status word with the END bit set if the END or
EOS message occurred before or during that call. The
END bit is cleared in the status word at the start of any
subsequent programming message.
SRQI 4096
The SRQI bit indicates if a device is requesting service.
This bit is set in the status word whenever the SRQ* line
is asserted. The bit is cleared whenever the GPIB SRQ*
line is unasserted.
CMPL 256
The CMPL bit indicates that the operation relating to this
status information is complete. This bit is always set, and
is useful in identifying the status word from other
responses.