Page of GC20-1801-10 As Updated April 1, 1981 by TNL GN25-0837
Loading and Savinq Discontiguous Saved Segments of
Addresses: Numbers
L Since the NAMESYS macro requires you to specify page and segment
numbers, and the CMSXGEN, DOSGEN, and VSAMGEN procedures require you to
enter hexadecimal addresses, you may find the following reference
information useful.
1 Page = 4K = X'1000' 1 Segment = 64K = X'10000' To convert a page number to a segment number, divide the page number by
16.
since one segment is 10000 in hexadecimal, then 20000 is segment 2, 100000 is segment 16, 1COOOO is segment 28, and so on.
The recommended procedure for loading and saving the discontiguous
saved segments as described in Figure 31 is:
1. During the system generation procedure (Step CMSXGEN EXEC procedure to load and save the
address 100000. 23), invoke the CMSSEG segment at
2. Perform the Installation Verification Procedure.
3. Redefine storage to 16M, IPL CMS and access the system disk again.
4. Invoke the DOSGEN procedure to load and save the INSTVSAM segment
at address FEOOOO. 5. Redefine storage to 2112K, IPL CMS and access the system disk
aqain.
6. Define the system name of the CMS/DOS segment to INSTVSAM by
issuing the CMS command:
set sysname cmsdos instvsam
7. Invoke the VSAMGEN EXEC procedure to load and save the CMSVSAM and CMSAMS segments at addresses iiOOOO and 170000, respectively.
8. Invoke the DOSGEN EXEC procedure to save the CMSDOS segment at
address 1FOOOO. The system name entry in the SYSNAMES table
defaults to CMSDOS. 9. Text files must have a filetype of TEXT. For example, after you
have updated an object module using VMFASM, the most recent object
file has a filetype such as TXTLOCAL. To use that text file here,
you must rename it to a filetype of TEXT. If there is currently a
text file on the system disk, you may want to rename it too, so
that your updated text file (which may reside on another disk) is
the one that is loaded.
loading and Saving the eMS/DOS Segment Called INSTVSAM Use the DOSGEN EXEC procedure to load and save the CMS/DOS segment
called INSTVSAM. This eMS/DOS segment is used only for the installation
of V5AM and Access Method Services. Part 3. Generating VH/370 (CP, CMS, RSCS, and IPCS) 269

or AS Apr1L lYijl by TNL GN25-0837
Loading and Saving Discontiguous Saved Segments Before you invoke DOSGEN to load the INSTVSAM segment, IPL CMS in a
virtual machine with 16M (16384K) of storage. The INSTVSAM segment will
be loaded near the top of storage, at 16256K (hexadecimal address FEOOOO). You can increase your virtual machine storage size, up to the maximum size defined for it in the VM/370 directory, by entering the DEFINE STORAGE command. After the DEFINE STORAGE command executes, you must
reload CMS. define storage 16m
ipl 190 At this point, you save the segment called INSTVSAM by
issuing the commands:
dosgen feOOOO instvsam
Be sure the DOSGEN EXEC is formatted on a CMS minidisk in either 800 or
lK blocks. The format of the DOSGEN command is: DOSGEN address [segmentnamel
address is the virtual storage location where the CMS/DOS segment
is to be loaded. This address is specified in
hexadecimal digits.
segmentname is the name of the segment to be loaded.
previously assigned a name to the CMS/DOS the NAHESYS macro. You must ha ve
segment with DOSGEN checks that the address
than X'20000', and less than 16M. contains valid characters, is greater
If an error is detected, the message DMSGEN095E INVALID ADDRESS 'address'
is issued and the command is terminated. DOSGEN then checks for a read/write A-disk on which to write the C!S loader work file; if none is accessed, it issues an error message and
the command terminates. DMSGEN006E NO READ/WRITE A-DISK ACCESSED Next, DOSGEN loads all the text files needed for DOS simulation. The
text files are loaded starting at the address specified on the DOSGEN command. If there are any unresolved external references, OOSGEN terminates with the message DMSGENlllE DOSGEN FAILED DUE TO LOAD ERRORS DOSGEN then assigns a storage key of X'D' to the segment
it. If an error is detected, one of the following messages
and DOSGEN terminates: DMSGEN412S DOSGEN FAILED DUE TO SETKEY ERRORS DHSGEN141S DOSGEN FAILED DUE TO SAVESYS ERRORS 270 IBM VM/370 Planning and System Generation Guide
and saves
is issued