W83977ATF Datasheet, PDF (134/207 Pages) Winbond – WINBOND I/O

W83977ATF
PRELIMINARY
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
CR28 (Default 0x00)
Bit 7 - 5: Reserved.
Bit 4: IRQ Sharing selection.
= 0 Disable IRQ Sharing
= 1 Enable IRQ Sharing
Bit 3:Reserved
Bit 2 - 0: PRTMODS2 - PRTMODS0
= 0xx Parallel Port Mode
= 100 Reserved
= 101 External FDC Mode
= 110 Reserved
= 111 External two FDC Mode
CR2A (Default 0x00)
Bit 7: PIN57S
= 0 KBRST
= 1 GP12
Bit 6: PIN56S
= 0 GA20
= 1 GP11
Bit 5 - 4: PIN40S1, PIN40S0
= 00 CIRRX
= 01 GP24
= 10 8042 P13
= 11 Reserved
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Publication Release Date: Auguest 1997
Revision 0.51