Table of Contents
Advertisement
The conversion routine does all its work in general
registers.
You
must
load
registers
0,
1,
2,
14, and 15 with input to the routine.
Register usage is as follows:
Register
o
1
2
3-8
9-13
14
15
APPENDAGES
Use
Must be loaded with a 4-byte value of the
form
TTRN,
where
TT
is
the
number
of the track
relative to the ceginning of the data set, R is
the identification of the block on that
track,
and
N
is the concatenation number of the data
set.
(0 indicates the first or only
data
set
in
the
concatenation, 1 indicates the second,
etc. )
Must ce loaded with the
address
of
the
data
extent block (DEB) of the data set.
Must
be
loaded
with the address of an 8-byte
area that is to receive the actual
address
of
the
clock
to
De
processed.
The
converted
address
is
of
the
form
MBBCCHHR,
where
M
indicates which extent entry in the data extent
block
is
associated
with
the
direct-access
program (0 indicates the first extent, 1
inal-
cates
the
second, etc.); BB indicates the bin
nunber of the direct-access
vol un,e;
CC
indi-
cates
the
cylinder
address;
hE
indicates the
actual track address; and R indicates the block
identification.
Are not used by the conversion routine.
Are used by the conversion routine and are
not
restored.
Must
be
loaded
with
the
contrel is to
te
returned
the conversion routine.
address
to
which
after
execution
of
Is
used
by
the
conversion routine as a base
register and IToust te loaded with the address at
which the
conversion
routine
is
to
receive
control.
For additional control over I/O oferations, you may write appendages,
which
must
be
entered
into
the
SVC library.
Descriptions of these
routines and their coding specifications
are
contained
in
the
"EXCP
Macro-Instruction" section of this publication.
L-
AND E- FORMS OF XDAP MACRO-INSTRUCTION
You
may
use
the
L-
form
of
the
XDAP
macro-instruction
for a
macro-expansion consisting of only a parameter list, or the E- form
for
a
macro-expansion
consisting
of only executable instructions.
The L-
and E- forms are described in Appendix B of the IBM Systero/360 Operating
System: Control Program Services, Form C28-6S41.
Note:
The BLKREF parameter is ignored ty
the
"L"
macro-instruction.
The
field
may
be
supplied
macro-instruction or moved into the lOB by you.
104
form
of
the
XDAP
in the E-form of the
Advertisement
Table of Contents
