0 |
Must be loaded with a 4-byte value of the relative track number.
If entered at CVTPCNVT+0, this value must be in the form TTR n,
where: - TT
- The track number relative to the beginning of the data set
- R
- The block identification on that track
- n
- If the DEB is for a partitioned concatenation, (the
DSORG field in the DCB indicates PO), then supply the concatenation
number for the data set. A value of 0 indicates the first data set,
1 indicates the second data set and so forth. If your partitioned
concatenation includes PDSEs or z/OS® UNIX directories, each of them is
represented by a dummy extent in the DEB. EXCP and EXCPVR are not
valid for those extents. If the data set is not concatenated or the
concatenation is not partitioned, set to 0.
If entered at CVTPCNVT+12, this value must
be in the form TTTR, where: - TTT
- The track number relative to the beginning of the data set
- R
- The block identification on that track
This entry point is intended for any type of data set.
|
1 |
Must be loaded with the address of the data extent block (DEB)
of the data set. Each DEB resides below 16 MB. When you call the
+0 entry point, the called routine clears the high order byte of
this register. When you call the +12 entry point, this byte must
contain X'00'. Note that if the DEB31UCB bit is
zero, the UCB address field is three bytes in DEBUCBA. If the DEB31UCB
bit is one, the UCB address field is four bytes in DEBUCBAD. |
2 |
Must be loaded with the address of an 8-byte area that is to
receive the actual address of the block to be 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 indicates
the second, and so forth)
- BB
- Two bytes of zeros
- CC
- Low order 16 bits of the cylinder number. The cylinder
number is 28 bits on all currently supported DASD.
- HH
- The actual track number in the low order four bits
and the high order twelve bits of the cylinder number in the high
order twelve bits.
- R
- The block number.
|
3–8 |
Not used by the conversion routine. |
9–12 |
Used by the conversion routine and not restored. |
13 |
Used by the conversion routine and not restored.
If you call the +12 entry point, the high order three bytes must contain
zero and the low order byte must be as set as follows: - If the DEB is for a partitioned concatenation, (the DSORG field
in the DCB indicates PO), then supply the concatenation number for
the data set. A value of 0 indicates the first data set, 1 indicates
the second data set and so forth.
- If the data set is not concatenated or the concatenation is not
partitioned, set to 0.
|
14 |
Must be loaded with the address to which control is to be returned
after execution of the conversion routine. |
15 |
Used by the conversion routine as a base register and must
be loaded with the address where the conversion routine is to receive
control (from field CVTPCNVT of the CVT). |