X-Authentication-Warning: delorie.com: mailnull set sender to djgpp-bounces using -f Message-ID: <3C7ECCA1.D260CB16@yahoo.com> From: CBFalconer Organization: Ched Research X-Mailer: Mozilla 4.75 [en] (Win98; U) X-Accept-Language: en MIME-Version: 1.0 Newsgroups: comp.os.msdos.djgpp Subject: Re: memory image References: <002101c1c092$4b43fe70$770510ac AT inf DOT umcc DOT cu> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Lines: 24 Date: Fri, 01 Mar 2002 01:18:16 GMT NNTP-Posting-Host: 12.90.175.251 X-Complaints-To: abuse AT worldnet DOT att DOT net X-Trace: bgtnsc05-news.ops.worldnet.att.net 1014945496 12.90.175.251 (Fri, 01 Mar 2002 01:18:16 GMT) NNTP-Posting-Date: Fri, 01 Mar 2002 01:18:16 GMT To: djgpp AT delorie DOT com DJ-Gateway: from newsgroup comp.os.msdos.djgpp Reply-To: djgpp AT delorie DOT com Jade wrote: > > As u know EXE files include some header info like the stack size, > PSP etc. They are not memory image. > COM executables does not include this info at the header so they > are usefull for doing things like boot loaders. That's why I need > to compile a COM file. I need to make a boot loader for a sample > system I'm writting. Com files start executing with CS=DS=ES=SS at 0100h. They are 16 bit systems only, and own the complete DOS memory arena at start up. The stack is set to point to the top of the 64k segment. They can't be made with the DJGPP system - you need to use an assembler or older compilers set for the 'tiny' model. The exe is then converted with exe2bin, which comes with your DOS system (or maybe used to come). -- Chuck F (cbfalconer AT yahoo DOT com) (cbfalconer AT XXXXworldnet DOT att DOT net) Available for consulting/temporary embedded and systems. (Remove "XXXX" from reply address. yahoo works unmodified) mailto:uce AT ftc DOT gov (for spambots to harvest)