FDC37C78-HT Standard Microsystems (SMSC), FDC37C78-HT Datasheet - Page 7

• Manufacturer Part Number: FDC37C78-HT
• Manufacturer: Standard Microsystems (SMSC)

Specifications of FDC37C78-HT

• Package Type: TQFP
• Lead Free Status / RoHS Status: Compliant

PIN NO.
22,
38
21
27
29
33
31
20
23
24
Reset
Read Disk Data
Write
Data
Head
Select
Direction
Control
Step Pulse
Disk Change
DRVDEN 0,
DRVDEN 1
Density Select
NAME
RESET
nRDATA
nWDATA
nHDSEL
nDIR
nSTEP
nDSKCHG
DRVDEN0,
DRVDEN1
DENSEL
DESCRIPTION OF PIN FUNCTIONS
SYMBOL
FLOPPY DISK INTERFACE
BUFFER
TYPE
OD20
OD20
OD20
OD20
OD20
OD20
IS
IS
IS
7
This active high signal resets the chip and
must be valid for 500 ns minimum. The effect
on the internal registers is described in the
appropriate
registers are not affected by this reset.
Raw serial bit stream from the disk drive, low
active. Each falling edge represents a flux
transition of the encoded data.
This active low high current driver provides
the encoded data to the disk drive.
falling edge causes a flux transition on the
media.
This high current output selects the floppy
disk side for reading or writing. A logic "1" on
this pin means side 0 will be accessed, while
a logic "0" means side 1 will be accessed.
This high current low active output determines
the direction of the head movement. A logic
"1" on this pin means outward motion, while a
logic "0" means inward motion.
This active low high current driver issues a
low pulse for each track-to-track movement of
the head.
This input senses that the drive door is open
or that the diskette has possibly been
changed since the last drive selection. This
input is inverted and read via bit 7 of I/O
address 3F7H.
Indicates the drive and media selected. Refer
to
CR1F.
Indicates whether a low (250/300 Kb/s) or
high (500 Kb/s) data rate has been selected.
This is determined by the IDENT bit in
Configuration Register 3.
configuration
section.
DESCRIPTION
registers
The
CR03,
configuration
CR0B,
Each