Updating video bios int 10 igneous rock and carbon 14 dating

01 Set cursor type Entry: CH=cursor start line CL=cursor end line Exit: None Notes: 1) Legal values are 0-7 (CGA) and 0-13 (MDA) Default values are 6,7 (CGA) and 11,12 (MDA) 2) Setting CH=20 will make the cursor disappear 02 Set cursor position Entry: BH=page number DH=row DL=column Exit: None 03 Get cursor position Entry: BH=page number Exit: CH=cursor start line CL=cursor end line DH=row DL=column 04 Read light pen position Entry: None Exit: AH=status (0=not triggered,1=triggered) BX=pixel column CH=pixel row (modes 04-06) CX=pixel row (modes 0D-13) DH=character row DL=character column 05 Select display page Entry: AL=page number 0-1 for modes 0F,10 0-3 for modes 02-03(CGA),0E 0-7 for modes 00-01,02-03(EGA/MCGA/VGA),07(EGA/VGA),0D Exit: None 06 Scroll window up Entry: AL=number of lines to scroll or 0 to blank window BH=blanking attribute CH=upper left corner of window (row) CL=upper left corner of window (column) DH=lower right corner of window (row) DL=lower right corner of window (column) Exit: None 07 Scroll window down Entry: Same as function 06 Exit: None 08 Read attribute and character at cursor Entry: BH=page number Exit: AH=attribute (text modes) AL=character 09 Write attribute and character at cursor Entry: AL=character BH=page number BL=attribute (text modes) or color (graphics modes) CX=repetition count Exit: None Notes: 1) The repetition count is valid only for the current row in graphics modes.

2) If bit 7 of BL is set for graphics modes the character is XORed with the current character contents.

updating video bios int 10-39

2) When fixed disks are installed the original floppy disk interrupt is revectored to INT 40.

3) Cylinder and head numbers are 0-based, sector numbers are 1-based.

If the carry flag is cleared then the key will be ignored otherwise the scan code in AL will be used.

52 EDD media eject intercept Entry: DL=drive code Exit: CF=0 AH=0 (allow eject) CF=1 AH=error code (disallow eject) Note: This function is called by INT 13 function 46 to check if the eject media request is allowed.

INT 10 Video Note: When an EGA or VGA is installed the original video interrupt is revectored to INT 42.