http://git.dujemihanovic.i2p?p=nameless-os.git;a=blob;f=boot/x86/a20.s;h=b1c86cee6fb9521693c5e91ce146f78e585f3748;hb=5abfd3ff79ee9a4eb10334ac6729205cc1a35546
search: re summary | shortlog | log | commit | commitdiff | tree history | raw | HEAD Slim down print.s [nameless-os.git] / boot / x86 / a20.s 1 ; Some routines for managing the A20 line 2 3 ; Check if A20 is enabled 4 ; Based on <https://wiki.osdev.org/A20_Line#Testing_the_A20_line> 5 check_a20: 6 pushf 7 push ds 8 push es 9 push di 10 push si 11 12 cli 13 14 xor ax, ax 15 mov es, ax 16 17 not ax 18 mov ds, ax 19 20 mov di, 500h 21 mov si, 510h 22 23 mov al, byte [es:di] 24 push ax 25 26...