W83977ATF Datasheet, PDF (136/207 Pages) Winbond – WINBOND I/O

Bit 1 - 0: PIN103S1, PIN103S0
= 00 IRQ14
= 01 GP14
= 10 PLEDO
= 11 Reserved
CR2D (Default 0x00)
Test Modes: Reserved for Winbond.
CR2E (Default 0x00)
Test Modes: Reserved for Winbond.
CR2F (Default 0x00)
Test Modes: Reserved for Winbond.
W83977ATF
PRELIMINARY
11.2 Logical Device 0 (FDC)
CR30 (Default 0x01 if PNPCSV = 0 during POR, default 0x00 otherwise)
Bit 7 - 1: Reserved.
Bit 0: = 1 Activates the logical device.
= 0 Logical device is inactive.
CR60, CR 61 (Default 0x03, 0xf0 if PNPCSV = 0 during POR, default 0x00, 0x00 otherwise)
These two registers select FDC I/O base address [0x100:0xFF8] on 8 byte boundary.
CR70 (Default 0x06 if PNPCSV = 0 during POR, default 0x00 otherwise)
Bit 7 - 4: Reserved.
Bit 3 - 0: These bits select IRQ resource for FDC.
CR74 (Default 0x02 if PNPCSV = 0 during POR, default 0x04 otherwise)
Bit 7 - 3: Reserved.
Bit 2 - 0: These bits select DRQ resource for FDC.
= 0x00 DMA0
= 0x01 DMA1
= 0x02 DMA2
= 0x03 DMA3
= 0x04 - 0x07 No DMA active
CRF0 (Default 0x0E)
FDD Mode Register
Bit 7: FIPURDWN
This bit controls the internal pull-up resistors of the FDC input pins RDATA, INDEX, TRAK0,
DSKCHG, and WP.
= 0 The internal pull-up resistors of FDC are turned on.(Default)
= 1 The internal pull-up resistors of FDC are turned off.
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Publication Release Date: Auguest 1997
Revision 0.51