W83L517D_05 Datasheet, PDF (104/133 Pages) Winbond – LPC I/O for Notebook

W83L517D/W83L517D-F
9.4 Extension FDD Mode (EXTFDD)
In this mode, the W83627HF changes the printer interface pins to FDC input/output pins, allowing the
user to install a second floppy disk drive (FDD B) through the DB-25 printer connector. The pin
assignments for the FDC input/output pins are shown in Table 6-1.
After the printer interface is set to EXTFDD mode, the following occur:
(1) Pins _MOB# and _DSB# will be forced to inactive state.
(2) Pins _{DSKCHG#, RDATA#, WP#, TRAK0#, INDEX#} will be logically ORed with pins PD4-PD0 to
serve as input signals to the FDC.
(3) Pins PD4-PD0 each will have an internal resistor of about 1K ohm to serve as pull-up resistor for
FDD open drain/collector output.
(4) If the parallel port is set to EXTFDD mode after the system has booted DOS or another operating
system, a warm reset is needed to enable the system to recognize the extension floppy drive.
9.5 Extension 2FDD Mode (EXT2FDD)
In this mode, the W83627HF changes the printer interface pins to FDC input/output pins, allowing the
user to install two external floppy disk drives through the DB-25 printer connector to replace internal
floppy disk drives A and B. The pin assignments for the FDC input/output pins are shown in Table6-1.
After the printer interface is set to EXTFDD mode, the following occur:
(1) Pins _{MOA#, DSA#, MOB#,} and _DSB# will be forced to inactive state.
(2) Pins _{DSKCHG#, RDATA#, WP#, TRAK0#,} and _INDEX# will be logically ORed with pins PD4-PD0 to serve as
input signals to the FDC.
(3) Pins PD4-PD0 each will have an internal resistor of about 1K ohm to serve as pull-up resistor for FDD open
drain/collector output.
(4) If the parallel port is set to EXT2FDD mode after the system has booted DOS or another operating system, a
warm reset is needed to enable the system to recognize the extension floppy drive.
10. GENERAL PURPOSE I/O
W83L517D provides 38 input/output ports that can be individually configured to perform a simple
basic I/O function or a pre-defined alternate function. Those 38 GP I/O ports are divided into five
groups, each group contains 6,8,8,8,8 ports from group 1 to group 5. The first group is configured
through control registers in logical device 7, the second group in logical device 8,the third ,the
fourth,and the fifth group in logical device 9. Users can configure each individual port to be an input or
output port by programming respective bit in selection register (CRF0: 0 = output, 1 = input). Invert
port value by setting inversion register (CRF2: 0 = non-inverse, 1 = inverse). Port value is read/written
through data register (CRF1). Table 7.1 and 7.2 gives more details on GPIO's assignment. In
addition, GPIO1 is designed to be functional even in power loss condition (VCC or VSB is off). Figure
7.1 shows the GP I/O port's structure. Right after Power-on reset, those ports default to perform basic
input function except ports in GPIO1 which maintains its previous settings until a battery loss
condition.
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