LOCATE
DEVICE CHARACTERISTICS (DEVTYPE) MACRO-INSTRUCTION
The
DEVTYPE
macro-instruction
is
used
to
request
information
relating
to
the
characteristics
of
an
I/O
device,
and
to
cause
this
information
to
be
placed
into
a
specified
area.
r----------T----------T------------------------------------------------,
I Nawe I
Operation
I
Operand
I
~----------+----------+------------------------------------------------~
I
[symbol]
I
DEVTYPE
I
ddloc-addrx,area-addrx[,DEVTAB]
I
l
__________
L
__________
i
_______________________________
_________________
J
ddloc-addrx
specifies
the
address
of
a
double
word
that
contains
the
symbolic
name
of
the
DD
statement
to
which
the
device
is
assigned.
The
name
must
be
left
justified
in
the
double
word,
and
must
be
followed
by
blanks
if
the
name
is
less
than
eight
characters.
The
double
word
need
not
be
on
a
double-wcrd
boundary.
area-addrx
specifies
the
address
of
an
area
into
which
the
device
information
is
to
be
placed.
The
area
can
be
either
two
full
words
or
five
full
wordS,
depending
on
whether
or
not
the
DEVTAB
operand
is
specified.
The
area
must
bt
on
a
full
word
toundary.
DEVTAB
If
DEVTAB
is
specified,
and
the
device
is
a
direct-access
device,
five
full
words
of
information
are
placed
into
your
area.
If
DEVTAB
is
specified,
and
the
device
is
not
a
direct-access
device,
two
full
words
of
information
are
placed
into
your
area.
If
DEVTAB
is
not
specified,
two
full
words
of
information
are
placed
into
your
area.
Note:
Any
reference
to
a durrmy
DD
statement
macro-instruction
will
cause
invalid
information
to
the
output
area.
in
be
the
DEVTYPE
placed
in
Device
Characteristics
Information
The
following
information
is
placed
into
your
area:
Word 1
Device
Code
from
the
UCB
in
which:
Byte
1
Byte
2
Byte
3
Byte
4
bit
0
Unassigned
bit
1
Overrunable
Device
bit
2
Burst/Byte
Mode
bit
3
Data
Chaining
bit
4-7
Model
Code
Optional
Features
Device
Classes
Unit
Type
1
yes
1 =
burst
1
yes
Note:
Bit
settings
for
Byte
2
--
Optional
Features
are
noted
in
the
ueB
format
and
field
description
in
the
System
Control
Blocks
publication.
Word 2
126
Maximum
tlock
size.
For
direct-access
devices,
this
value
is
the
maximum
size
of
an
un
keyed
block;
for
magnetic
or
paper
tape,
this
value
is
the
maximum
block
size
allowed
by
the
operating
system.
For
all
other
devices,
this
value
is
the
maximum
block
size
accepted
by
the
device.
To Next Page
Loading...
Need help?
General