FDC37C669-MS View Datasheet(PDF) - SMSC -> Microchip

Part Name

Description

Manufacturer

FDC37C669-MS

PC 98/99 Compliant Super I/O Floppy Disk Controller with Infrared Support

SMSC -> Microchip 

TAPE DRIVE REGISTER (TDR)

Address 3F3 READ/WRITE

This register is included for 82077 software compatability.

The robust digital data separator used in the

FDC37C669 does not require its characteristics modified

for tape support. The contents of this register are not

used internal to the device. The TDR is unaffected by a

software reset. Bits 2-7 are tri-stated when read in this

mode.

Table 4- Tape Select Bits

TAPE SEL1

0

0

1

1

TAPE SEL2

0

1

0

1

DRIVE

SELECTED

None

1

2

3

Table 5 - Internal 4 Drive Decode - Normal

DIGITAL OUTPUT REGISTER

DRIVE SELECT OUTPUTS

(ACTIVE LOW)

Bit 7 Bit 6 Bit 5 Bit 4 Bit1 Bit 0 nDS3 nDS2 nDS1 nDS0

X

X

X

1

0

0

1

1

1

0

X

X

1

X

0

1

1

1

0

1

X

1

X

X

1

0

1

0

1

1

1

X

X

X

1

1

0

1

1

1

0

0

0

0

X

X

1

1

1

1

MOTOR ON OUTPUTS

(ACTIVE LOW)

nMTR3 nMTR2 nMTR1 nMTR0

nBIT 7 nBIT 6 nBIT 5 nBIT 4

nBIT 7 nBIT 6 nBIT 5 nBIT 4

nBIT 7 nBIT 6 nBIT 5 nBIT 4

nBIT 7 nBIT 6 nBIT 5 nBIT 4

nBIT 7 nBIT 6 nBIT 5 nBIT 4

Table 6 - Internal 4 Drive Decode - Drives 0 and 1 Swapped

DIGITAL OUTPUT REGISTER

DRIVE SELECT OUTPUTS

(ACTIVE LOW)

MOTOR ON OUTPUTS

(ACTIVE LOW)

Bit 7 Bit 6 Bit 5 Bit 4 Bit1 Bit 0 nDS3 nDS2 nDS1 nDS0 nMTR3 nMTR2 nMTR1 nMTR0

X

X

X

1

0

0

1

1

0

1

nBIT 7 nBIT 6 nBIT 4 nBIT 5

X

X

1

X

0

1

1

1

1

0

nBIT 7 nBIT 6 nBIT 4 nBIT 5

X

1

X

X

1

0

1

0

1

1

nBIT 7 nBIT 6 nBIT 4 nBIT 5

1

X

X

X

1

1

0

1

1

1

nBIT 7 nBIT 6 nBIT 4 nBIT 5

0

0

0

0

X

X

1

1

1

1

nBIT 7 nBIT 6 nBIT 4 nBIT 5

24

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