DIGITAL-LOGIC Microspace MSB900L User Manual page 32

DIGITAL-LOGIC AG
CMOS Map
continued...
Location Description
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
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
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
Landing Zone
Write Precompensation
Heads
Sectors/Track
Byte 0
1Fh
Bits 7-0 = Lower 8 bits of Cylinders
Byte 1
20h
Bits 7-2 = Lower 6 bits of Landing Zone
Bits 1-0 = Upper 2 bits of Cylinders
Byte 2
21h
Bits 7-4 = Lower 4 bits of Write Precompensation
Bits 3-0 = Upper 4 bits of Landing Zone
Continued...
= Internal Floppy Disk Controller
0 = Disabled
1 = Enabled
= Internal IDE Controller
0 = Disabled
1 = Enabled
= Hard Drive 0 Custom Flag
0 = Disabled
1 = Enabled
= Hard Drive 0 IDE Flag
0 = Disabled
1 = Enabled
= Hard Drive 1 Custom Flag
0 = Disabled
1 = Enabled
= Hard Drive 1 IDE Flag
0 = Disabled
1 = Enabled
10bits
10bits
10bits
08bits
08bits
MSB900/L Detailed Technical Manual V1.0
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range 0-1023
range 0-1023
range 0-15
range 0-254
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