"You can try to run eComStation on Macintosh computers. Make experiments with eComStation installatin CD. The boot stops at message related to "A20 gate" (?)"

Macintosh keyboard probably doesn't have an A20 Gate switch to switch memory into protected mode!

Mike .currently booted from USB_stick into PartedMagic 4.9 (courtesy JvW and DFSee), with SATA HDD powered off by keyswitch on this HP dx5150MT Business Desktop, due extensive earlier series of thunderstorms in waves - to mitigate any damage.

>>"You can try to run eComStation on Macintosh computers. Make experiments with eComStation installatin CD. The boot stops at message related to "A20 gate" (?)"

>Macintosh keyboard probably doesn't have an A20 Gate switch to switch memory into protected mode!

Worse yet: Macintosh has NO A20 gate, because it's BIOS stuff which was dropped in Macintosh firmware

See [url] (short)

?Unpatched versions of GRUB fail to start up because they try to access the A20 gate, which fails on Intel Macs because Apple got rid of that kind of legacy hardware. (Many Linux distros have the patch nowadays.)

[url] (long)

In short: GRUB had to be patched to boot properly w/o init A20 gate. The quest is, whether OS2Loader only should be patched, or the kernel also. (Hint: patch FreeLdr to skip that test and replace OS2loader with FreeLDR?)

> лНФМН НОСАКХЙНБЮРЭ ЯРЮРЭЧ, ЙЮЙХЕ ХГЛЕМЕМХЪ МСФМН ЯДЕКЮРЭ Б eCS ДКЪ ОНКМНЖЕММНИ ОНДДЕПФЙХ UEFI (ЕЯРЭ КХ ОПНАКЕЛШ Я FAT32 КХЖЕМГХЕИ Х Р.О.)

that should be nice research, actually. GRUB2 could be installed in EFI, crosscompiled from Linux. The quest is the same, whether it's enough or kernel should be patched too to support UEFI.

> яСДЪ ОН ЯННАЫЕМХЪЛ ОНКЭГНБЮРЕКЕИ, НМХ СЯОЕЬМН СЯРЮМЮБКХБЮЧР eComStation МЮ UEFI ОКЮРШ СФЕ ЯЕЦНДМЪ (2011), МХЙЮЙХУ ОПЕОЪРЯРБХИ МЕ БЯРПЕВЮЧР.

because UEFI on PC (EFI 2.0) has BIOS compatibility mode,and boots in that mode -- which is not-so-much on Macs' EFI (EFI 1.1). Instead, Win7 and so on are booted from EFI in EFI mode, with proper loader.