0040h:0000h
COM1 Base Port Address
0040h:0002h
COM2 Base Port Address
0040h:0004h
COM3 Base Port Address
0040h:0006h
COM4 Base Port Address
0040h:0008h
LPT1 Base Port Address
0040h:000Ah
LPT2 Base Port Address
0040h:000Ch
LPT3 Base Port Address
0040h:000Eh
LPT4 Base Port Address
0040h:0010h
Equipment List
0040h:0012h
POST Status
0040h:0013h
Base Memory Size
0040h:0015h
Battery Status
0040h:0017h
Keyboard Shift Status
0040h:0018h
Keyboard Extended Shift Status
0040h:0019h
Alternate Keyboard Entry
0040h:001Ah
Keyboard Buffer Head Pointer
0040h:001Ch
Keyboard Buffer Tail Pointer
0040h:001Eh
Keyboard Buffer
0040h:003Eh
Diskette Drive Recalibrate Status
0040h:003Fh
Diskette Drive Motor Status
0040h:0040h
Motor Off Counter
0040h:0041h
Last Diskette Drive Operation Status
0040h:0042h
Diskette Drive Controller Status Information
0040h:0049h
Display Mode
0040h:004Ah
Number of Columns in Current Mode
0040h:004Ch
Length of Regen Buffer
0040h:004Eh
Starting Address of Regen Buffer
0040h:0050h
Cursor Positions for all Pages
0040h:0060h
Cursor Start and End Scan Lines
0040h:0062h
Current Display Page
0040h:0063h
CRT Controller Base Address
0040h:0065h
Current Setting of the Mode Control Register
0040h:0066h
Current Setting of the Color Select Register
0040h:0067h
Cassette / RAM Expansion
0040h:006Ch
Timer Counter
0040h:0070h
Timer Overflow Flag
0040h:0071h
Break Key State
0040h:0072h
Reset State Flag
0040h:0074h
Last Fixed Disk Operation Status
0040h:0075h
Number of Fixed Disks
0040h:0076h
Reserved
0040h:0077h
Reserved
0040h:0078h
Time Out Values for Parallel Printers
0040h:007Ch
Time Out Values for RS 232 Comms Lines
0040h:0080h
Keyboard Buffer Start Offset Pointer
0040h:0082h
Keyboard Buffer End Offset Pointer
0040h:0084h
Number of Rows on Display, minus 1
0040h:0085h
Character Height
0040h:0087h
Reserved
0040h:0089h
Reserved
0040h:008Bh
Diskette Media Control
0040h:008Ch
Fixed Disk Controller Status
0040h:008Dh
Fixed Disk Controller Error Status
0040h:008Eh
Fixed Disk Interrupt Control
0040h:008Fh
Reserved
0040h:0090h
Diskette Drive 0 Media State
0040h:0091h
Diskette Drive 1 Media State
0040h:0092h
Reserved
0040h:0094h
Drive 0 Current Track
0040h:0095h
Drive 1 Current Track
0040h:0096h
Keyboard Status and Type Flags
0040h:0097h
Keyboard LED Status
0040h:0098h
Pointer to User Wait Complete Flag
0040h:009Ch
User Wait Counter
0040h:00A0h
Wait Active Flag
0040h:00A1h
Reserved
0040h:00A8h
Pointer to EGA Parameters
0040h:00ACh
Reserved
0040h:00F0h
Intra Applications Communications Area (ICA)
0050h:0000h
Print Screen Status
0050h:0001h
Reserved
0050h:0004h
Phantom Drive Status
0050h:0005h
Reserved
F000h:FFF0h
Far Jump to POST
F000h:FFF5h
ROM BIOS Release Date
F000h:FFFCh
Reserved
F000h:FFFEh
System Model ID
Copyright © 1985 to 2022 Beta Systems Last modified: Wednesday, January 05, 2022 .