Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!mailrus!csd4.csd.uwm.edu!cs.utexas.edu!uunet!yale!bunker!shap From: shap@bunker.UUCP (Joseph D. Shapiro) Newsgroups: comp.sys.ibm.pc Subject: Re: Writing to extended memory Keywords: extended memory Message-ID: <6916@bunker.UUCP> Date: 22 Aug 89 13:56:16 GMT References: <1145@hcx1.UUCP> <693@jc3b21.UUCP> <12048@orstcs.CS.ORST.EDU> <1989Aug18.092544.5202@ziebmef.uucp> Reply-To: shap@clunker.UUCP (Joseph D. Shapiro) Distribution: usa Organization: ISC-Bunker Ramo, an Olivetti Company, Shelton, Ct Lines: 24 In article <1989Aug18.092544.5202@ziebmef.uucp> stephen@ziebmef.UUCP (Stephen M. Dunn) writes: >In article kaldis@topaz.rutgers.edu (Theodore A. Kaldis) writes: >$In article <12048@orstcs.CS.ORST.EDU> cowl1453@neptune.uucp (Tim Cowles) writes: >$> Is there a reasonable way to write, during runtime and without using a >$> virtual disk drive (same problem!), to the memory in my machine above 1M ?? >$> (It seems like it can be done, the virtual disk device driver does it. ) > To access extended memory, you have to kick the 286 into "protected" mode, >which is the mode OS/2 runs in. (The 286 in an AT-clone normally runs in well, to split hairs, and maybe the difference is significant to the original poster, it is possible on most 286 machines to access about 64k of the extended memory without going into protected mode. If you call microsoft, they will send you, *free*, HIMEM.SYS (an arbitrator for this 64k of memory) and instructions on how to ask it for buffers. So -- if 64k is enough, AND your 286 machine allows it (a fairly safe bet), you may be in luck. -- __--__--__--__--__--__--__--__--__--__--__--__--__--__--__--__--__--__--__--__ Joe Shapiro "My other car is a turbo... ISC-Bunker Ramo ...too." {decvax,yale,philabs,oliveb}!bunker!shap