Talk:A20 Line: Difference between revisions

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"Don't forget to restore the original bootsector identifier." Why is it important? [[User:Adek336|Adek336]] 21:44, 1 August 2008 (UTC)
"Don't forget to restore the original bootsector identifier." Why is it important? [[User:Adek336|Adek336]] 21:44, 1 August 2008 (UTC)

Since we are talking about the OS-specific bootloader here, it's not. The OS would know (and probably doesn't care) that the memory image of its own bootloader was slightly self-modified. If the OS happens to boot from a generic bootloader, then the OS had best not assume anything about the bootloader except what is in the bootloader's specs.<br>
However, this article definitely needs an additional section about INT15h AX=2400h and 2401h.<br>
Maybe there should also be a mention that the Compaq method, the HP Vectra method, and the Port 0xEE method also exist -- and pointing to external links for descriptions. [[User:Bewing|Bewing]] 20:53, 2 August 2008 (UTC)

Revision as of 20:53, 2 August 2008

Contents

I think this topic needs some practical information about the A20 line. (Added stub tag). - Combuster 16:12, 17 December 2006 (CST)

There is some information about it on OS FAQ Wiki... I will adapt it when I have the time... JJeronimo 14:41, 23 December 2006 (CST)
The pre-pentium remark seems to be invalid. It has nothing to do with the processor, only with the chipset used. - Combuster 08:33, 24 December 2006 (CST)
Yes, yes... on my old 486 DX it worked... JJeronimo 11:29, 24 December 2006 (CST)

"Don't forget to restore the original bootsector identifier." Why is it important? Adek336 21:44, 1 August 2008 (UTC)Reply

Since we are talking about the OS-specific bootloader here, it's not. The OS would know (and probably doesn't care) that the memory image of its own bootloader was slightly self-modified. If the OS happens to boot from a generic bootloader, then the OS had best not assume anything about the bootloader except what is in the bootloader's specs.
However, this article definitely needs an additional section about INT15h AX=2400h and 2401h.
Maybe there should also be a mention that the Compaq method, the HP Vectra method, and the Port 0xEE method also exist -- and pointing to external links for descriptions. Bewing 20:53, 2 August 2008 (UTC)Reply