W83697HF_05 Datasheet, PDF (71/102 Pages) Winbond – LPC I/O

W83697HF
= 00 Normal (Default)
= 01 Normal
= 10 1 ( Forced to logic 1)
= 11 0 ( Forced to logic 0)
Bit 1: DISFDDWR
= 0 Enable FDD write.
= 1 Disable FDD write(forces pins WE, WD stay high).
Bit 0: SWWP
= 0 Normal, use WP to determine whether the FDD is write protected or not.
= 1 FDD is always write-protected.
CRF2 (Default 0xFF)
Bit 7 - 6: FDD D Drive Type
Bit 5 - 4: FDD C Drive Type
Bit 3 - 2: FDD B Drive Type
Bit 1 - 0: FDD A Drive Type
CRF4 (Default 0x00)
FDD0 Selection:
Bit 7: Reserved.
Bit 6: Precomp. Disable.
= 1 Disable FDC Precompensation.
= 0 Enable FDC Precompensation.
Bit 5: Reserved.
Bit 4 - 3: DRTS1, DRTS0: Data Rate Table select (Refer to TABLE A).
= 00 Select Regular drives and 2.88 format
= 01 3-mode drive
= 10 2 Meg Tape
= 11 Reserved
Bit 2: Reserved.
Bit 1:0: DTYPE0, DTYPE1: Drive Type select (Refer to TABLE B).
CRF5 (Default 0x00)
FDD1 Selection: Same as FDD0 of CRF4.
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