National Instruments GPIB-SCSI-A, Руководство пользователя

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Chapter 5 S Mode Functions
© National Instruments Corp. 5-27 GPIB-SCSI-A User Manual
config (continued)
configuration from an external controller). If PP2 is 1, the
GPIB-SCSI-A uses PP subset PP2 (local configuration via the
ppc function). When PP subset PP2 is used, the
GPIB-SCSI-A ignores remote parallel poll configurations.
You can use the BufMode argument to change the buffering
method that the GPIB-SCSI-A uses for data transfer during the
brd,bwrt,rd,
and
wrt
commands. See Table 5-1 for
proper values of the BufMode argument. For a complete
description of each buffering method, refer to the section titled
Buffering Methods in Chapter 3, Technical Information.
Table 5-1. Buffering Methods for Data Transfer Commands
Description BufMode
Do not change the buffering method. 0
Use the No Buffering method. 1
Use the Single Buffering method. 2
Use the Double Buffering method. 3
The Size argument is used to change the size of the internal
buffer used by the GPIB-SCSI-A. This buffer is used by the
brd,bwrt,rd,
and
wrt
commands when Single or Double
Buffering is enabled. The actual buffer size is set to the lower
of the Size argument and the amount of DRAM available for
use. If Size is zero, no change is made to the current buffer
size.
The information returned by the GPIB-SCSI-A contains three
pieces: the SW2 switch setting, the SW1 switch setting, and
the current buffer size.