FDC37N869 View Datasheet(PDF) - SMSC -> Microchip

Part Name

Description

MFG CO.

FDC37N869

5V and 3.3V Super I/O Controller with Infrared Support for Portable Applications

SMSC -> Microchip 

Prev 41 42 43 44 45 46 47 48 49 50 Next

PHASE

Command

Result

INVALID CODES

DATA BUS

R/W D7 D6 D5 D4 D3 D2 D1 D0

REMARKS

W

- - - - - Invalid Codes - - - - -

Invalid Command Codes

(NoOp - FDC37N869 goes

into Standby State)

R

- - - - - - - ST0 - - - - - - -

ST0 = 80H

PHASE

Command

Result

LOCK

DATA BUS

R/W

D7

D6 D5 D4 D3 D2 D1 D0

REMARKS

W LOCK 0 0

1

0 1 0 0 Command Codes

R

0

0 0 LOCK 0 0 0 0

SC is returned if the last command that was issued was the Format command. EOT is returned if the last

command was a Read or Write.

Note: These bits are used internally only. They are not reflected in the Drive Select pins. It is the user’s

responsibility to maintain correspondence between these bits and the Drive Select pins (DOR).

Data Transfer Commands

All of the Read Data, Write Data and Verify type commands use the same parameter bytes and return the same

results information, the only difference being the coding of bits 0-4 in the first byte.

An implied seek will be executed if the feature was enabled by the Configure command. This seek is completely

transparent to the user. The Drive Busy bit for the drive will go active in the Main Status Register during the seek

portion of the command. If the seek portion fails, it will be reflected in the results status normally returned for a

Read/Write Data command. Status Register 0 (ST0) would contain the error code and C would contain the cylinder

on which the seek failed.

Read Data

A set of nine bytes is required to place the FDC in the Read Data Mode. After the Read Data command has been

issued, the FDC loads the head (if it is in the unloaded state), waits the specified head settling time (defined in the

Specify command), and begins reading ID Address Marks and ID fields. When the sector address read off the

diskette matches with the sector address specified in the command, the FDC reads the sector’s data field and

transfers the data to the FIFO.

After completion of the read operation from the current sector, the sector address is incremented by one and the

data from the next logical sector is read and output via the FIFO. This continuous read function is called “Multi-

Sector Read Operation”. Upon receipt of TC, or an implied TC (FIFO overrun/underrun), the FDC stops sending

data but will continue to read data from the current sector, check the CRC bytes, and at the end of the sector,

terminate the Read Data Command. N determines the number of bytes per sector (see Table 34 below). If N is

set to zero, the sector size is set to 128. The DTL value determines the number of bytes to be transferred. If DTL is

less than 128, the FDC transfers the specified number of bytes to the host. For reads, it continues to read the

entire 128-byte sector and checks for CRC errors. For writes, it completes the 128-byte sector by filling in zeros. If

N is not set to 00 Hex, DTL should be set to FF Hex and has no impact on the number of bytes transferred.

SMSC DS – FDC37N869

Page 46

Rev. 11/09/2000

Share Link: