Date: Thu, 7 Dec 2000 17:03:36 -0500 (EST) From: Larry Baird <lab@gta.com> To: small@freebsd.org Cc: Luigi Rizzo <rizzo@aciri.org> Subject: Re: non-standard floppy formats ? Message-ID: <200012072203.RAA39082@gta.com> In-Reply-To: <200012070036.eB70a2X00376@iguana.aciri.org>
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In article <200012070036.eB70a2X00376@iguana.aciri.org> you wrote: > Hi, > i was trying to make picobsd work with non-standard floppy > formats (1722k specifically), but i am having a hard time. > Basically, the boot2 code says "Not ufs", i think this is > because it tries to read from the disk using the BIOS > and the BIOS only knows about the 80 track/18 sector > format, and not the 82*21 format used for 1722k. Am i correct ? > This is really bad because in the additional 300K there would > be a lot of stuff one could squeeze in. I think the problem is in boot1.s of boot2. Look at the function read(). The first thing is does is do an int13 call to get the BIOS configuration of the floppy. The result that is causing you a problem is "cylinders per track" (returned in register cl). You could hardcode the code after the int13 to set register cl to your new floppy geometry. Larry -- ------------------------------------------------------------------------ Larry Baird | http://www.gnatbox.com Global Technology Associates, Inc. | Orlando, FL Email: lab@gta.com | TEL 407-380-0220, FAX 407-380-6080 To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-small" in the body of the message
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