IBM PC BIOS and MS/PC-DOS Interrupt Services SummaryNumber Address Type Description
------- ------- ----.. --------------------------------------------
\00 CPU Divide by Zero
\01 CPU Single Step
\02 CPU Nonmaskable
\03 CPU Breakpoint
\04 CPU Overflow
\05 BIOS Print Screen
\06 hdw Reserved
\07 hdw Reserved
\08 hdw Time of Day
\09 hdw Keyboard
\0A hdw Reserved
\0B hdw Communications (8259)
\0C hdw Communications
\0D hdw Disk
\0E hdw Diskette
\0F hdw Printer
\10 BIOS Video I/O - services to handle video output
Int AH AL BH BL CH CL DH DL DS:SI ES:DI
10 00 vm Set Video Mode
.. .. .. .. .. .. .. .. .. .. .. ..
10 01 ls le Set Cursor Line Start, End
.. .. .. .. .. .. .. .. .. .. .. ..
10 02 Pg Rw Cl Set Cursor Row,Col on Page *1
.. .. .. .. .. .. .. .. .. .. .. ..
10 03 Pg Get Cursor Row,Col,Line Start,End on Page
.. .. .. .. ls le Rw Cl .. .. .. ..
10 04 Get Light Pen Down,Graphics x,y,
dn .. grafx grafy Rw Cl .. .. .. .. Text Row,Column
10 05 Pg Set Page
.. .. .. .. .. .. .. .. .. .. .. ..
10 06 n at r1 c1 r2 c2 Scroll up n lines, in area from r1,c1 to
.. .. .. .. .. .. .. .. .. .. .. .. r2,c2 fill with attribute
10 07 n at r1 c1 r2 c2 Scroll down n lines, in area from r1,c1
.. .. .. .. .. .. .. .. .. .. .. .. to r2,c2 fill with attribute
10 08 Pg Get attribute and character at current
at ch .. .. .. .. .. .. .. .. .. .. cursor position on page
10 09 ch Pg at count Fill attribute and character at current
.. .. .. .. .. .. .. .. .. .. .. .. cursor position on page for count
10 0A ch pg count Fill character
10 0B sw co
\11 BIOS Equipment Check
\12 BIOS Memory
\13 BIOS Diskette/Disk
\14 BIOS Serial Communications
\15 BIOS Cassette, System Services
\16 BIOS Keyboard
\17 BIOS Parallel Printer
\18 BIOS ROM BASIC Loader
\19 BIOS Bootstrap Loader
\1A BIOS Time of Day
\1B BIOS Keyboard Break
\1C BIOS Timer Tick
\1D BIOS Video Initialization
\1E BIOS Diskette Parameters
\1F BIOS Video Graphics Characters, second set
\20 DOS General Program Termination
\21 DOS DOS Services Function Request
Int AH AL BH BL CH CL DH DL DS:SI ES:DI
21 00 Terminate Process
21 01 Console Input
ch
21 02 ch Console Output
21 03 Auxiliary Input
ch
21 04 ch Auxiliary Output
21 05 ch Printer Output
21 06 ch Direct Console IO
ch also uses Zero Flag
21 07 Keyboard Input
ch no Ctrl-C check
21 08 Keyboard Input
ch
21 09 strng zz Console Output String
21 0A Console Input String
strng zz
21 0B Keyboard Status
fl
21 0C fc strng zz Flush then call Function
ch
21 0D Disk Reset
21 0E
\22 DOS Called Program Termination Address
\23 DOS Control Break Termination Address
\24 DOS Critical Error Handler
\25 DOS Absolute Disk Read
\26 DOS Absolute Disk Write
\27 DOS Terminate and Stay Resident
\28 DOS r Reserved for DOS
\29 DOS * Fast Screen Write
\2A DOS Microsoft Networks - Session Layer Interrupt
\2B DOS r Reserved and unknown
\2C DOS r Reserved and unknown
\2D DOS r Reserved and unknown
\2E DOS r Reserved and unknown
\2F DOS Multiplex Interrupt
\30 DOS * Far jump instruction for CP/M-style calls
\31 DOS r Reserved and unknown
\32 DOS r Reserved and unknown
\33 DOS Used by Microsoft Mouse Driver
\34 DOS r Reserved and unknown
\35 DOS r Reserved and unknown
\36 DOS r Reserved and unknown
\37 DOS r Reserved and unknown
\38 DOS r Reserved and unknown
\39 DOS r Reserved and unknown
\3A DOS r Reserved and unknown
\3B DOS r Reserved and unknown
\3C DOS r Reserved and unknown
\3D DOS r Reserved and unknown
\3E DOS r Reserved and unknown
\3F DOS r Reserved and unknown
\40 BIOS r Hard Disk BIOS
\41 BIOS r Hard Disk Parameters (except PC1)
\42 BIOS r Pointer to screen BIOS entry (EGA, VGA, PS/2)
\43 BIOS r Pointer to EGA initialization parameter table
\44 BIOS First 128 Graphics Characters
\45 BIOS r Reserved by IBM (not initialized)
\46 BIOS Pointer to hard disk 2 params (AT, PS/2)
\47 BIOS r Reserved by IBM (not initialized)
\48 BIOS PCjr Cordless Keyboard Translation
\49 BIOS PCjr Non-Keyboard Scancode Translation Table
\4A BIOS r Real-Time Clock Alarm (Convertible, PS/2)
4B BIOS Reserved for BIOS
4C BIOS Reserved for BIOS
4D BIOS Reserved for BIOS
4E BIOS Reserved for BIOS
4F BIOS Reserved for BIOS
50 BIOS Reserved for BIOS
51 BIOS Reserved for BIOS
52 BIOS Reserved for BIOS
53 BIOS Reserved for BIOS
54 BIOS Reserved for BIOS
55 BIOS Reserved for BIOS
56 BIOS Reserved for BIOS
57 BIOS Reserved for BIOS
58 BIOS Reserved for BIOS
59 BIOS Reserved for BIOS
\5A BIOS r Cluster Adapter BIOS entry address
\5B BIOS*r IBM (cluster adapter?)
\5C BIOS NETBIOS interface entry port
\60 10-Net Network
61 User Program Interrupts (availible for general use)
62 User Program Interrupts (availible for general use)
63 User Program Interrupts (availible for general use)
64 User Program Interrupts (availible for general use)
65 User Program Interrupts (availible for general use)
66 User Program Interrupts (availible for general use)
\67 Used by LIM & AQA EMS, EEMS
68 Reserved by IBM
69 Reserved by IBM
6A Reserved by IBM
6B Reserved by IBM
6C Reserved by IBM
6D Reserved by IBM
6E Reserved by IBM
6F Reserved by IBM
70 Reserved by IBM
71 Reserved by IBM
72 Reserved by IBM
73 Reserved by IBM
74 Reserved by IBM
75 Reserved by IBM
76 Reserved by IBM
77 Reserved by IBM
78 Reserved by IBM
79 Reserved by IBM
7A Reserved by IBM
7B Reserved by IBM
7C Reserved by IBM
7D Reserved by IBM
7E Reserved by IBM
7F Reserved by IBM
\6C System Resume Vector (Convertible)
\6F some Novell and 10-Net API functions
\70 IRQ08 Real Time Clock Interrupt (AT, PS/2)
\71 IRQ09 LAN Adapter 1
\72 IRQ10 (AT, XT/286, PS/2) Reserved
\73 IRQ11 (AT, XT/286, PS/2) Reserved
\74 IRQ12 Mouse Interrupt (PS/2)
\75 IRQ13 Coprocessor Error
\76 IRQ14 Hard Disk Controller (AT, PS/2)
\77 IRQ15 (AT, XT/286, PS/2) Reserved
\7C IBM REXX88PC command language
80
-85 ROM BASIC
86
-F0 Used by BASIC Interpreter When BASIC is running
F1
-FF Reserved by IBM Interprocess Communications Area
\F8 ICA *r Set Shell Interrupt (OEM)
\F9 ICA *r OEM SHELL service codes
\FA ICA r USART ready (RS-232C)
\FB ICA r USART RS ready (keyboard)
\FE ICA *r used on '283 & '386
\FF ICA *r used on '283 & '386