PQI DiskOnModule, Datasheet

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15
[Duplicate Data, Error and Feature register]
During word access, the address space occupied by the Data Register interferes with the
space occupied by the Error register and Feature register, and reference cannot be made to
these registers. Therefore, the PC Card ATA Standard provides an area where the copy of
each register does not duplicate in the contiguous I/O mode and memory map mode. The
even-numbered address of the data register is provided in the offset "08h", and the
odd-numbered address of the data register is located in the offset "09h". The copy of
Error/Feature register is provided at the ODh.
Duplicate Data register
D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0
Data Word
Odd Data Byte Only Even or Even-Odd Data Byte
Duplicate registers Access
Data register CE2# CE# A0 Offset Data Bus
Word Data register 0 0 0 0h,8h D15-D0
Word Data register 0 0 1 1h,9h D15-D0
Even Byte Data register 1 0 0 0h,8h D7-D0
Odd Byte Data register 1 0 1 9h D7-D0
Odd Byte Data register 0 1 × 8h,9h D15-D8
Error/Feature register 1 0 1 1h,0Dh D7-D0
Error/Feature register 0 1 × 0h,1h D15-D8
Error/Feature register 0 0 × 0Ch,0Dh D15-D8
Initial value of task file register
After resetting and execution of the Execute Device Diagnostic command, the task file register
is initialized as follows:
Sector Count register 01h
Sector Number register 01h
Cylinder Lo register 00h
Cylinder High register 00h
Device/Head register A0h