National Instruments GPIB-SCSI-A, Руководство пользователя

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S Mode Functions Chapter 5
GPIB-SCSI-A User Manual 5-26 © National Instruments Corp.
config - Read/Change GPIB-SCSI-A
Configuration
Type: General Use function
Purpose: Use
config
when you want the GPIB-SCSI-A to change or
report its current operating configuration.
Format:
Bit 7 6 5 4 3 2 1 0
Byte
0 Opcode = DEH
1 High 4 bits of Size Rsvd PP2 BufMode
2 Middle Byte of Size
3 Least Significant Byte of Size
4 Allocation Length
5 Reserved
Remarks: Use this command when you want to find out the current
configuration of the GPIB-SCSI-A. You can also use this
command to change some of the configuration parameters
within the box.
The Allocation Length indicates the number of bytes that the
Initiator has allocated for returned configuration data. An
Allocation Length of zero indicates that no bytes of
configuration data are transferred. Any other value indicates
the maximum number of bytes that can be transferred, up to 5.
The GPIB-SCSI-A terminates the Data In phase when
Allocation Length bytes have transferred or when all available
configuration data have transferred to the Initiator, whichever
is less.
The PP2 argument is used to indicate what type of parallel poll
configurations the GPIB-SCSI-A should accept. If PP2 is 0,
the GPIB circuitry of the GPIB-SCSI-A uses the IEEE 488
Parallel Poll (PP) interface function subset PP1 (remote