DOS ain't dead

Jwasm 2.0 and 64 bit real mode (Announce)

posted by Jack , Fresno, California USA, 14.10.2009, 10:34

> When we have such a feature [over 4-GB RAM] in some XMS manager, how
> would it be utilized? ...

I agree with Japheth. All of my drivers will support "over 4-GB RAM".

XMGR will make it available for drivers/programs that can use it. New
XMS request codes [to be defined] shall specify use of "over 4-GB RAM".
UIDE and RDISK will ask the XMS manager (HIMEMX, JEMMEX, XMGR) if "over
4-GB RAM" is available, and if so, they will request it. If not, they
will request normal XMS memory below 4-GB, same as they do now.

With minor changes, UIDE can be upgraded from its current 2-GB limit to
handle caches up to 4-GB, using "over 4-GB RAM". With a fast CPU, its
cache "overhead" should still be manageable, even at a 4-GB cache size.
I was SURPRISED that a 2-GB cache was no-problem, and CPUs keep getting
faster!

With a bit more work, RDISK can be upgraded to handle multiple 2-GB RAM
disks using "over 4-GB RAM". I want to keep each RAM disk at 2-GB, so
older DOS systems having only FAT-16 logic can still make use of RDISK.

All the above changes should have no impact on current programs. They
can still request XMS memory below 4-GB using the currently-defined XMS
command codes. UIDE setting caches up to 4-GB, and RDISK setting more
than one 2-GB RAM disk, also shouldn't affect current programs. These
are "management issues" that only affect UIDE and RDISK.

Japheth and I must decide (A) when "over 4-GB RAM" is required, and (B)
what new XMS logic is needed for it. Microsoft no-longer supports DOS
and will never update their HIMEM driver, thus this task is for Japheth
and me. If his HIMEMX/JEMMEX and my XMGR get the same new logic, they
can go on being used "interchangeably" for XMS work, same as now.

---
(Account disabled on user's request.)

Complete thread:

• Jwasm 2.0 and 64 bit real mode - swf, 12.10.2009, 22:49 (Announce)
  • Jwasm 2.0 and 64 bit real mode - Rugxulo, 13.10.2009, 02:31
  • Jwasm 2.0 and 64 bit real mode - Japheth, 13.10.2009, 11:08
    • Jwasm 2.0 and 64 bit real mode - Jack, 13.10.2009, 20:32
    • Jwasm 2.0 and 64 bit real mode - RayeR, 14.10.2009, 00:36
      • Jwasm 2.0 and 64 bit real mode - Japheth, 14.10.2009, 06:08
        • Jwasm 2.0 and 64 bit real mode - RayeR, 14.10.2009, 13:18
          • Jwasm 2.0 and 64 bit real mode - ecm, 14.10.2009, 14:14
            • Jwasm 2.0 and 64 bit real mode - Rugxulo, 19.10.2009, 10:44
      • Jwasm 2.0 and 64 bit real mode - Jack, 14.10.2009, 10:34
        • Jwasm 2.0 and 64 bit real mode - RayeR, 14.10.2009, 13:41
        • Jwasm 2.0 and 64 bit real mode - swf, 14.10.2009, 16:01
          • "Extended" Memory With XMGR. - Jack, 14.10.2009, 19:51
            • "Extended" Memory With XMGR. - swf, 15.10.2009, 18:57
              • "Extended" Memory With XMGR. - Jack, 15.10.2009, 19:42
        • Jwasm 2.0 and 64 bit real mode - Zyzzle, 15.10.2009, 07:35
          • Over 4-GB For UIDE/RDISK. - Jack, 15.10.2009, 09:19