Christophe Lucas wrote:
I think this sentence is referred to the value 36 put in the disk parameter table.Koala GNU (koala.gnu@tiscalinet.it) wrote:Hi all, I am looking at the boot code in bootsect.S (2.4)and I have some doubt. I tried to search the answers to my questions on marc.theaimsgroup.com and on google bu I haven't found them. 1) In the bootsect code the first thing that is done is to copy the boot sector to 0x90000 and move the program count to 0x9000, go. Why it is necessary move the code there? is It not possible continue the process from 0x7C00?As said in code : "High doesn't hurt. Low does." => This is done to preserve the firmware data areas in low memory. (I copy it from : http://www.moses.uklinux.net/patches/lki-1.html#ss1.4 )
Excuse me. I have already read this document but it seems does not contain the format of the disk parameter table.2) Another step is to move the parameters table from 0x78:0 to 0x9000:0x4000-12. WHat are the info contained in this table?The disk parameter table for the firstCan you send me a link to a site that specify these info?http://www.moses.uklinux.net/patches/lki.html
Withouth these info I am not able to understand these three line of code movb $36, 0x4(%di) # patch sector count movw %di, %fs:(%bx) movw %es, %fs:2(%bx) I know that in 2.6 the boot from floppy using native code is not supported anymore, but I am still interested on this stuff. Thanks in advance for your helpOther correct me, if I am make mistakes. I am a newbie, and can and make mistakes ;-)
