FDC37B78X View Datasheet(PDF) - SMSC -> Microchip

Part Name

Description

Manufacturer

FDC37B78X

Enhanced Super I/O Controller with ACPI Support, Real Time Clock and Consumer IR

SMSC -> Microchip 

SYMBOL

H/HDS

HLT

HUT

LOCK

MFM

NAME

Head Address

Head Load Time

Head Unload

Time

MFM/FM Mode

Selector

DESCRIPTION

Selected head: 0 or 1 (disk side 0 or 1) as encoded in the sector

ID field.

The time interval that FDC waits after loading the head and before

initializing a read or write operation. Refer to the Specify

command for actual delays.

The time interval from the end of the execution phase (of a read or

write command) until the head is unloaded. Refer to the Specify

command for actual delays.

Lock defines whether EFIFO, FIFOTHR, and PRETRK parameters

of the CONFIGURE COMMAND can be reset to their default

values by a "software Reset". (A reset caused by writing to the

appropriate bits of either tha DSR or DOR)

A one selects the double density (MFM) mode. A zero selects

single density (FM) mode.

MT

N

NCN

ND

TABLE 21 - DESCRIPTION OF COMMAND SYMBOLS

Multi-Track

When set, this flag selects the multi-track operating mode. In this

Selector

mode, the FDC treats a complete cylinder under head 0 and 1 as

a single track. The FDC operates as this expanded track started

at the first sector under head 0 and ended at the last sector under

head 1. With this flag set, a multitrack read or write operation will

automatically continue to the first sector under head 1 when the

FDC finishes operating on the last sector under head 0.

Sector Size Code

This specifies the number of bytes in a sector. If this parameter is

"00", then the sector size is 128 bytes. The number of bytes

transferred is determined by the DTL parameter. Otherwise the

sector size is (2 raised to the "N'th" power) times 128. All values

up to "07" hex are allowable. "07"h would equal a sector size of

16k. It is the user's responsibility to not select combinations that

are not possible with the drive.

N Sector Size

New Cylinder

Number

0 128 Bytes

1 256 Bytes

2 512 Bytes

3 1024 Bytes

……

The desired cylinder number.

Non-DMA Mode

Flag

When set to 1, indicates that the FDC is to operate in the non-

DMA mode. In this mode, the host is interrupted for each data

transfer. When set to 0, the FDC operates in DMA mode,

interfacing to a DMA controller by means of the DRQ and nDACK

signals.

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