User manual

DIGITAL-LOGIC AG MSM800SEV/SEL/BEV/XEV/XEL Detailed Manual V1.7
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CMOS Map continued...
Location Description
14h Equipment
Bits 7-6 = Number of Diskette Drives
00 = One diskette drive
01 = Two diskette drives
10, 11 = Reserved
Bits 5-4 = Primary Display Type
00 = Adapter with option ROM
01 = CGA in 40 column mode
10 = CGA in 80 column mode
11 = Monochrome
Bits 3-2 = Reserved
Bit 1 = Math Coprocessor Presence
0 = Not installed
1 = Installed
Bit 0 = Bootable Diskette Drive
0 = Not installed
1 = Installed
15h Base Memory Size (in kB) - Low Byte
16h Base Memory Size (in kB) - High Byte
17h Extended Memory Size (in kB) - Low Byte
18h Extended Memory Size (in kB) - High Byte
19h Extended Drive Type - Hard Drive 0
1Ah Extended Drive Type - Hard Drive 1
1Bh Custom and Fixed (Hard) Drive Flags
Bits 7-6 = Reserved
Bit 5 = Internal Floppy Disk Controller
0 = Disabled
1 = Enabled
Bit 4 = Internal IDE Controller
0 = Disabled
1 = Enabled
Bit 3 = Hard Drive 0 Custom Flag
0 = Disabled
1 = Enabled
Bit 2 = Hard Drive 0 IDE Flag
0 = Disabled
1 = Enabled
Bit 1 = Hard Drive 1 Custom Flag
0 = Disabled
1 = Enabled
Bit 0 = Hard Drive 1 IDE Flag
0 = Disabled
1 = Enabled
1Ch Reserved
1Dh EMS Memory Size Low Byte
1Eh EMS Memory Size High Byte
1Fh - 24h Custom Drive Table 0
These 6 Bytes (48 bits) contain the following data:
Cylinders 10bits range 0-1023
Landing Zone 10bits range 0-1023
Write Precompensation 10bits range 0-1023
Heads
08bits range 0-15
Sectors/Track 08bits range 0-254
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