IBTAB(4) — Silicon Graphics
NAME
ibtab − format of ibtab file
DESCRIPTION
The ibtab file is an unordered collection of entries, each of which describes one IEEE 488 bus node. Its format is understood by the ibtab(3N) subroutine package, which is used by programs such as iib(1M). The format and the package are loosely patterned after getpw(3C) and passwd(4). Each entry consists of a line with colon-separated fields. Numeric items are interpreted according to the usual C rules: leading 0x implies hex, leading 0 implies octal, default decimal.
FIELDS
File
the device file used to access the node.
Cfile
the device file used to control (ioctl) the node, either /dev/lib0 or /dev/ib8.
Node
driver node number. In most cases, this field should be the low order 3 bits of the minor device number (which is the digit in the device filename.) The controller’s node number must be 0. Note that this is not the same thing as the node’s 488 address. See ib(7) for further details.
Flags
flags pertaining to the node, as defined in the include file <sys/ib_ioctl.h>. This field may be numeric or symbolic, with symbols separated by the ’|’ character or white space. Possible flags are: SWAB, if the node does byte-reversed IEEE 488 bus i/o; VALID, if the node is for real; SRQ, if the node can assert SRQ; PPE, if the node can respond to parallel polls; PPC, if the node can be remotely configured for parallel polls; SC, if the node is system controller.
Tag
the IEEE 488 bus address of the node.
Ppr
the parallel poll response. The low-order 3 bits specify which line the node uses for parallel poll responses. This field is significant only if the PPC or PPE flags are present.
Comment
ignored.
Lines beginning with the ’#’ character are ignored.
There must be entries for each node on the bus, including two IRIS.
EXAMPLE
# sample entry
# node 1, /dev/ib1
# controlled by /dev/ib0
# byte-reversed, can srq and ppoll
# gpib address 19
# ppoll line 3
/dev/ib1:/dev/ib0:1:VALID|SWAB|SRQ|PPE:19:03:board 0 node 1
SEE ALSO
Version 2.5 — April 22, 1987