At 08:32 AM 8/13/2006 +0200, Japheth wrote: > > Don't see exactly where this would happen in a supported configuration, > > since EMM386 requires HIMEM/XMS manager presence and handles UMB's > > internally. Nonstandard, unsupported configurations, well, can always > plan > > for that later. > >Don't know if the configuration I'm often using is nonstandard, but it uses >UMBPCI to provide a 64 kB segment at D000 and EMM386 to provide EMS and VCPI. >Then Emm386 tells "UMB handler already installed, not providing another one".
I'd consider that pretty nonstandard since you've already paid the VM86 overhead price with EMM386 so there shouldn't be much need for UMBPCI, barring an application which doesn't use VDS and/or can't and won't set up its own DMA buffers external to upper memory properly. Outside of UMB's you normally have identity mapping on real and extended memory. EMM386 can always match and exceed UMBPCI in upper memory maps. UMBPCI's strongest feature is the avoidance of all the VM86 chicanery while supporting UMBs. Anyway, how would code get to the new A20 control remap routines you don't want turned on without the new UMB handler installed? The feedback message you listed indicates the revector chaining which supports the A20 control routines wouldn't occur. Even if it could, I'm not sure how mapping in and out the 64K HMA would have much effect without an example. Kernel people have stated they have entry and exit of FreeDOS covered with the proper A20 call(s). ------------------------------------------------------------------------- Using Tomcat but need to do more? Need to support web services, security? Get stuff done quickly with pre-integrated technology to make your job easier Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642 _______________________________________________ Freedos-devel mailing list Freedos-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freedos-devel
