Hi!
VCPI was a superset of EMS, right?
I don't think so, no.
VCPI can be added to EMM386 to let it coexist with DOS extenders.
VCPI itself does not provide EMS.
EMS can exist in hardware on 8086, where DOS extenders cannot exist.
EMS itself is not related to VCPI.
The other complication was the different versions (e.g. XMSv2 versus
the bigger 386 variant v3)
I don't think I remember _versions_ of XMS. EMS, yes.
XMS 2 only supports up to 64 MB, XMS 3 supports more.
Because you cannot have so much XMS on 286, the XMS 3
interface is designed specifically for 386 and newer.
EMS 3.2 only supports pages of 16 kB size in a single
64 kB page frame at a fixed location, like "d000:0000".
EMS 4.0 supports 4 kB pages and lets you put them at
any multiple of 4 kB place in the first megabyte. It
no longer needs a page frame. EMM386 NOEMS actually is
for "no frame, 4.0 access only", not to disable EMS.
Regards, Eric
_______________________________________________
Freedos-devel mailing list
Freedos-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/freedos-devel
