PC97338 datasheet(32/221 Pages) NSC

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(PPM

Mode)

Group 10

Step. This pin provides an additional step signal in PPM mode

when PNF = 0. STEP is multiplexed with SLIN and ASTRB. See

Table 72 for more information.

Group 1

Terminal Count. This control signal from the DMA controller

indicates the termination of a DMA block transfer. TC is accepted

by the module (FDC, parallel port or SCC2) only when the

corresponding DMA acknowledge signal (DACK0, DACK1, DACK2

or DACK3, according to software configuration) is active. TC is

active high in PC-AT mode, and active low in PS/2 mode.

TRK0

(Normal

Mode)

Group 4

Track 0. This FDC input indicates to the controller that the head of

the selected floppy disk drive is at track zero.

(PPM

Mode)

Group 4

Track 0. This pin provides an additional Track 0 signal in PPM

Mode when PNF = 0.

TRK0 is multiplexed with PD1 (See Table 72 for more information).

VDD

48,

Power Supply signals. These pins input the 3.3 V or 5 V supply

voltage to the ChipVLJ and ChipVJG device.

VSS

Ground signals. These pins ground the ChipVLJ and ChipVJG

circuitry.

WAIT

Group 1

Wait. This signal is used in EPP mode, by the parallel port device,

to extend its access cycle. It is active low.

WAIT is multiplexed with BUSY and MTR1. See Table 72 for more

information.

WDATA

(Normal

Mode)

Group 10

FDC Write Data. This FDC output signal is the write

precompensated serial data that is written to the selected floppy

disk drive. Precompensation is software selectable.

(PPM

Mode)

Group 10

FDC Write Data. This pin provides an additional WDATA signal in

PPM mode when PNF = 0.

WDATA is multiplexed with PE. See Table 72 for more information.

WGATE

(Normal

Mode)

Group 10

FDC Write Gate. This FDC output signal enables the write circuitry

of the selected disk drive. WGATE is designed to prevent glitches

during power up and power down. This prevents writing to the disk

when power is cycled.

(PPM

Mode)

Group 10

FDC Write Gate. This pin provides an additional WGATE signal in

PPM mode, when PNF = 0.

WGATE is multiplexed with SLCT. See Table 72 for more

information.

(Normal

Mode)

Group 4

Write Protect. This FDC input indicates that the disk in the selected

drive is write protected.

(PPM

Mode)

Group 4

Write Protect. This pin provides an additional WP signal in PPM

mode, when PNF = 0.

WP is multiplexed with PD2. See Table 72 for more information.

Symbol

PQFP

TQFP

I/O and

Group #

Function

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