Pc-98 Bios Apr 2026

AH = 28h AL = mode 0 = 80x25 text (16 colors) 1 = 80x28 text (400 lines) 2 = 640x400 graphics (4 planes) 3 = 640x400 graphics (16 colors) INT 18h

AH = 40h DL = drive (0=A, 1=B, etc.) INT 18h Returns: CF = 0 if OK

AH = 41h DL = drive CX = track number (0–79 for 2HD) DH = head (0 or 1) CH = sector number (1–8 for 2HD) AL = number of sectors ES:BX = buffer INT 18h Returns: CF = 0 if OK pc-98 bios

AH = 29h Returns: AL = current mode Reset disk system

AH = 62h CX:DX = microseconds between interrupts INT 18h AH = 28h AL = mode 0 =

AH = 11h INT 18h ZF = 1 if no key ZF = 0 if key waiting → AX = scancode/ASCII

AH = 24h AL = character (ASCII) BH = color (0–15, 0=black) INT 18h pc-98 bios

AH = 22h Returns: DH = row, DL = column

AH = 21h DH = row (0–24 or 0–27) DL = column (0–79) INT 18h

AH = 70h INT 18h Returns: AX = BCD version (e.g., 0x0123 = v1.23)

msg db 'Hello from PC-98 BIOS!', 0