W83697HF Datasheet, PDF (147/167 Pages) Winbond – WINBOND I/O

W83697HF/F
CR26 (Default 0x00)
Bit 7 : SEL4FDD
= 0 Select two FDD mode.
= 1 Select four FDD mode
Bit 6 : HEFRAS
These two bits define how to enable Configuration mode. The corresponding power-on
setting pin is RTSA #(pin 49).
HEFRAS Address and Value
= 0 Write 87h to the location 2E twice.
= 1 Write 87h to the location 4Etwice.
Bit 5 : LOCKREG
= 0 Enable R/W Configuration Registers.
= 1 Disable R/W Configuration Registers.
Bit 4 : Reserved
Bit 3 : DSFDLGRQ
= 0 Enable FDC legacy mode on IRQ and DRQ selection, then DO register bit 3 is
effective on selecting IRQ
= 1 Disable FDC legacy mode on IRQ and DRQ selection, then DO register bit 3 is not
effective on selecting IRQ
Bit 2 : DSPRLGRQ
= 0 Enable PRT legacy mode on IRQ and DRQ selection, then DCR bit 4 is effective on
selecting IRQ
= 1 Disable PRT legacy mode on IRQ and DRQ selection, then DCR bit 4 is not effective
on selecting IRQ
Bit 1 : DSUALGRQ
= 0 Enable UART A legacy mode IRQ selecting, then MCR bit 3 is effective on selecting
IRQ
= 1 Disable UART A legacy mode IRQ selecting, then MCR bit 3 is not effective on
selecting IRQ
Bit 0 : DSUBLGRQ
= 0 Enable UART B legacy mode IRQ selecting, then MCR bit 3 is effective on selecting
IRQ
= 1 Disable UART B legacy mode IRQ selecting, then MCR bit 3 is not effective on
selecting IRQ
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Publication Release Date: Feb. 2002
Revision 0.70