User`s manual

DIGITAL-LOGIC AG MSLB-P5 Manual V0.3
PRELIMINARY 206
Continued
Extended Work Area
67 4 ROM check address
6B 1 CPU rate control
Timer Data Area
6C 2 Timer count low word
6E 2 Timer count high word
70 1 Timer overflow byte
System Data Area
71 1 Break pressed flag
72 2 Soft reset flag
Fixed Disk Data Area
74 1 Fdisk status
75 1 Number of fixed disks
76 1 Fixed disk control
77 1 Reserved
Serial and Parallel Timeout Counters
78 4 Lpt1-4 time-out values
7C 4 Com1-4 time-out values
Extended Keyboard Data Area
80 2 Key buffer start
82 2 Key buffer end
EGA/VGA Data Area
84 1 Number of video rows
85 2 Bytes per character
87 1 EGA Status A
88 1 EGA Status B
89 1 VGA Status A
8A 1 Display Combination Code index
Extended Diskette Area
8B 1 Last diskette data rate
Extended Fixed Disk Area
8C 1 FDisk status
8D 1 FDisk error value
8E 1 FDisk interrupt flag
Additional Extended Diskette Area
Offset Size Description
8F 1 Floppy info nibbles
90 4 Floppy state information
94 2 Floppy cylinder number
Additional Extended Keyboard Data Area
96 1 Keyboard control
97 1 Keyboard flag 2:
Bit .... Definition
0....... Scroll LED on
1....... Num lock LED on
2....... Caps lock LED on
4....... Ack code received
5....... Resend received
6....... LED being updated
7....... Keyboard error
Real Time Clock Area
Offset Size Description
98 4 RTC user flag
9C 2 RTC time low word
9E 2 RTC time high word
A0 1 RTC wait flag
Network Data Area
A1 7 Network work area
Extended EGA/VGA Data Area
A8 4 EGA/VGA environment pointer
Miscellaneous
AC-FF Reserved
100 1 Print screen flag
* If the BIOS supports the Extended BIOS Data Area, it uses the LPT4 address in the BIOS data area
(Offset 0E) for the Extended BIOS Data Area segment.