search for: use_chs_address

...+ +get_shift_keys: /* Provide a way for the user to force CHS addressing mode by pressing either Shift key */ + movb $0x02, %ah /* function: get keyboard shift flags */ + int $0x16 /* read keys; shift flags returned in AL */ + testb $0x03, %al /* left or right shift-keys pressed? */ + jnz use_chs_addressing /* if so, skip detection of BIOS type */ + +detect_bios_type: + /* try to use the BIOS extension for LBA (Logical Block Addressing). */ + movb (drive_number), %dl + movw $0x55aa, %bx /* required */ + movb $0x41, %ah /* query presence of extended BIOS functions (EBIOS) */ + int $0x13 /...

...+ +get_shift_keys: /* Provide a way for the user to force CHS addressing mode by pressing either Shift key */ + movb $0x02, %ah /* function: get keyboard shift flags */ + int $0x16 /* read keys; shift flags returned in AL */ + testb $0x03, %al /* left or right shift-keys pressed? */ + jnz use_chs_addressing /* if so, skip detection of BIOS type */ + +detect_bios_type: + /* try to use the BIOS extension for LBA (Logical Block Addressing). */ + movb (drive_number), %dl + movw $0x55aa, %bx /* required */ + movb $0x41, %ah /* query presence of extended BIOS functions (EBIOS) */ + int $0x13 /...

..._test +force_first_hard_disk: + movb $0x80, -6(%bp) /* offset from top-of-stack to drive number; force it to be first hard disk */ + movb $0x80, %dl /* change the drive number about to be used in detect_bios_type */ +shift_test: + testb $0x03, 0x0417 /* left or right shift-keys pressed? */ + jnz use_chs_addressing /* if so, skip detection of BIOS type */ + +detect_bios_type: + /* try to use the BIOS extension for LBA (Logical Block Addressing). */ + /* inherit drive number in DL from BIOS */ + movw $0x55aa, %bx /* required */ + movb $0x41, %ah /* query presence of extended BIOS functions (EBIOS) *...