DESCRIPTION OF PIN FUNCTIONS
PIN NO.
1
NAME
Density Select
SYMBOL
DENSEL
BUFFER
TYPE
OD48
DESCRIPTION
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.
This active low Schmitt Trigger input senses
from the disk drive that a disk is write
protected. Any write command is ignored.
This active low Schmitt Trigger input senses
from the disk drive that the head is
positioned over the outermost track.
This active low Schmitt Trigger input senses
from the disk drive that the head is
positioned over the beginning of a track, as
marked by an index hole.
These two outputs reflect bits 0 and 1
respectively of the Data Rate Register. At
power on, these two outputs are in a high
impedance state (refer to Table 50).
In Floppy Enhanced Mode 2 - These bits are
the Media ID 0,1 inputs. The value of these
bits can be read as bits 6 and 7 of the
Floppy Tape register.
Receiver serial data input.
Transmitter serial data output from Primary
Serial Port.
FDC37C666GT (Adapter Mode): Parallel
Port Configuration Control 0. During reset
active this input is read and latched to
define the address of the Parallel Port.
14
nWrite
Protected
nTrack 00
nWRTPRT
IS
13
nTR0
IS
12
nIndex
nINDEX
IS
19,18
Data Rate 0,
Data Rate 1
DRATE0,
DRATE1
O24
19,18
Media ID0,
Media ID1
I
SERIAL PORT INTERFACE
78,88
79
Receive Data
Transmit Data
RXD1,
RXD2
TXD1
I
O4
PCF0
I
9
SMSC [ SMSC CORPORATION ]
