Programming Interface - RadiSys EXM-9 Reference

4. Programming Interface

This chapter contains information needed to write custom software drivers for the
EXM-9. Anyone just using the EXM-9 as a BIOS-controlled interface to external
disks can skip reading this chapter.
The EXM-9 defines the following registers in the I/O space.
Bit 7 Bit 6 Bit 5 Bit 4 Bit 3
1 1 1 1
Device ID Register
Configuration Option Byte 1 Register
Data Register (16 bits)
Error/Write Precompensation Register
Sector Count Register
Sector Number Register
Cylinder Low Register
Bit 2 Bit 1 Bit 0 I/O Port
0 1 1 0
FLEN IDEN CDEN
4
100
102
1F0
1F1
1F2
1F3
1F4
1F5
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