X-Authentication-Warning: delorie.com: mail set sender to djgpp-bounces using -f Date: Wed, 02 Nov 2005 14:56:28 -0500 From: Diego Cueva Subject: RE: RE: Why the call instruction points 2 bytes before to the real start sub-routine In-reply-to: <3sscojFptcqiU3@news.dfncis.de> To: djgpp AT delorie DOT com Message-id: <000f01c5dfe7$85003570$2432a8c0@dcueva> MIME-version: 1.0 X-MIMEOLE: Produced By Microsoft MimeOLE V6.00.2800.1409 X-Mailer: Microsoft Outlook, Build 10.0.4024 Content-type: text/plain; charset=us-ascii Importance: Normal X-Priority: 3 (Normal) X-MSMail-priority: Normal Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from QUOTED-PRINTABLE to 8bit by delorie.com id jA2JwmJ1015382 Reply-To: djgpp AT delorie DOT com Errors-To: nobody AT delorie DOT com X-Mailing-List: djgpp AT delorie DOT com X-Unsubscribes-To: listserv AT delorie DOT com Precedence: bulk Hi: Thanks again for your response: The IPL program is working fine in botting time (not O.S. present). Booting from a diskette. The IPL is mounted to the first sectors of the diskette using rawrite tool. In VMWARE is working too. IPL is coded in assembler, and I can call SW interrupts, 0x13 for disk, 0x10 for video and so on. The IPL works fine. In the last hours I read documents about switching 32 bits mode, these is very complex for the purpose, and in this way, please, tell me what 16-bit "C" compiler (decent whit support) I can use for write a small Operating System for educational purposes? Thanks for your time. Att. Diego Cueva. -----Original Message----- From: Hans-Bernhard Broeker [mailto:broeker AT physik DOT rwth-aachen DOT de] Sent: Wednesday, November 02, 2005 12:53 To: djgpp AT delorie DOT com Subject: Re: Why the call instruction points 2 bytes before to the real start sub-routine ? Diego Cueva wrote: > com file not are my final objective. My Objective is creating a small > operating system to educational purposes, and I need compile C programs > with GCC that can execute in booting time. In that case, .com files are not just not your final goal, they're not even likely to be particularly useful as a stepping stone getting there. Code compiled by the DJGPP version of GCC strictly assumes a DPMI-like environment. You'ld have to recreate basically all of a DPMI server, and large parts of DOS, before this code will run reliably. To get an idea of what that means, have a good look at the CWSDPMI sources. It might end up being easier to embed FreeDOS, CWSDPMI and your program into a single binary image, instead. > To this moment I have a IPL program with a group small routines in > assemble compiled/linked with "as/ld". This is working fine. Working fine in what kind of environment? Called from DOS? > But link that with C compiled code is the WALL to climb now. Exactly. Wherein "WALL" is not just some bedroom wall or something --- it's more like the Eiger North side. -- Hans-Bernhard Broeker (broeker AT physik DOT rwth-aachen DOT de) Even if all the snow were burnt, ashes would remain. TODO1 SERVICES, INC. -TODO1- es la propietaria de la información contenida en este mensaje y sus anexos, que puede tener carácter confidencial y ha sido enviada para uso exclusivo del destinatario intencional. Si usted ha recibido este mensaje por error, por favor informe de ello al remitente a la mayor brevedad y elimine este mensaje y sus anexos. Está prohibido su uso, distribución, divulgación o almacenamiento, salvo autorización escrita de TODO1. Todo mensaje enviado y/o recibido por TODO1 es monitoreado por motivos operativos y actuando de acuerdo con prácticas de negocio y de seguridad legítimas. TODO1 SERVICES, INC. -TODO1- is the proprietary of the information contained herein and its attachments, that may have confidential character and has been sent to the intended recipient only. If you are not the intended recipient, please contact the sender immediately by replying to this e-mail and delete the message and its attachments. The use, forward, disclosure, record or retention of this message for any purpose whatsoever, is strictly prohibited, unless prior written authorization from TODO1. E-mails to and from TODO1 are monitored for operational reasons and in accordance with lawful business and security practices.