Computer diskette drive communication interface

A coupler of the present invention advantageously renders the read/write head of a diskette drive of a computer a data transfer port and preferably an input/output port suitable for connection with a peripheral device. The coupler includes a data transfer element, preferably a read/write element for transferring data by coupling with the read/write head of the diskette drive. The coupler includes a suitable arrangement for connecting the data transfer element with a peripheral device thus expanding the applications of the diskette drive. The coupler is sized for receipt in the diskette drive and preferably places the stationary data transfer element in a position relative to the read/write head of the diskette drive to allow data transfer therebetween when activated and said coupler is received in the diskette drive.

BACKGROUND OF THE INVENTION 
The present invention relates to the transfer of information between a 
computer and a peripheral device. In particular the invention relates to a 
new method and apparatus which renders the diskette drive of a computer an 
input, an output, or an input/output port whereby a communication channel 
is established between the personal computer and the peripheral device or 
peripheral devices. 
Personal computers contain a number of ports through which they communicate 
with peripheral devices such as keyboards, printers, modems, local area 
networks, scanners, compact disk drives and other peripherals which are 
not resident within the computer itself. Unfortunately the ports provided 
on the computer may not be suitable or available for the peripheral for 
which connection is desired. If additional ports are to be added, the 
computer has to be partially disassembled to install an appropriate 
circuit board and port. This installation is often difficult and in many 
cases is not undertaken by the user. 
There remains a need to allow an effective method and apparatus for 
providing a communication channel between a personal computer and an 
exterior peripheral. 
SUMMARY OF THE INVENTION 
A coupler according to the present invention is proposed which is 
receivable within the diskette drive of a computer and is adapted for 
rendering the read/write head of the diskette drive a port suitable for 
connection with peripheral device other than a conventional diskette. Most 
personal computers include at least one diskette drive and the invention 
recognizes that the read/write head of the diskette drive can be 
advantageously used as a port and preferably an input/output port. To 
render the system convenient to the user, the coupler is dimensioned for 
insertion in the diskette drive to position a means for coupling, provided 
on the coupler, in a manner to facilitate communication with the 
read/write head of the diskette drive. Data is transferred between the 
computer and a peripheral device via the coupler. 
According to an aspect of the invention the means for coupling includes a 
coil read/write element which is positioned for coupling to the read/write 
head of the diskette drive by means of electromagnetic induction. 
According to an aspect of the invention the means for coupling includes a 
stationary read/write element suitable for providing a capacitive coupling 
with the read/write head of the diskette drive. 
According to a further aspect of the invention the coupler has exterior 
dimensions of a standard diskette and is inserted within the diskette 
drive in the conventional manner. Such insertion aligns the read/write 
element of the coupler for transferring data to and from the read/write 
head of the diskette drive. 
The invention is also directed to the method of rendering the read/write 
head of a computer diskette drive an input/output port.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
A personal computer 2 having a diskette drive 4 is shown in FIGS. 1 through 
5 and is used in combination with the coupler 6 for connecting the 
external peripheral device 8 with the personal computer 2. FIG. 1 
illustrates the coupler 6 having an electrical or optical connection 10 by 
means of which data is transmitted between the coupler 6 and the external 
peripheral device 8. The coupler 6 is dimensionally compatible with the 
removeable media diskette drive 4 which typically would receive a 51/4" 
diskette or a 31/2" diskette or other standard diskettes. Thus the coupler 
6 is inserted into the diskette drive as if it where a standard diskette 
to render the read/write head of the diskette drive an input/output port 
by means of which serial data is exchanged between the personal computer 2 
and the external peripheral device 8. In some cases it will only be 
desirable to input or output data and thus the coupler need not 
necessarily render the read/write head an input/output device. 
The term "peripheral device" is used broadly and includes keyboards, 
printers, modems, memory cartridges, local area networks, facsimile 
machines, scanners, compact disk drives, memory storage arrangements and 
other peripherals which are not resident in the computer 2 itself. The 
term peripheral device does not include standard diskettes intended for 
receipt in the diskette drive. 
Details of the coupler 6 are shown in FIG. 6 in combination with a 
read/write head of a diskette drive. The coupler 6 in this embodiment is 
shown having an exterior periphery 20 corresponding to the shape of a 
standard 51/4" diskette to allow convenient insertion within the diskette 
drive. In this case the coupler 6 includes a rotating section 22 
appropriately configured to create the necessary timing pulse in 
combination with the timing hole 32. It should be noted that this rotary 
section is not required in all applications, however some diskette drives 
require a timing pulse to be received from a spinning diskette in order to 
determine the number of the sector that is currently at the read/write 
head. This timing pulse function will be coordinated with the coupler's 
signal conditioning and control electronics 24 such that both the external 
device and the diskette controller are synchronized with respect to 
apparent sector positioning. 
In some cases it is desirable to provide a small generator or alternator 23 
which is associated with the rotating portion 22 to generate electrical 
energy as portion 22 is driven by the diskette drive. The power can be 
provided to the signal conditioning and control circuitry 24 for powering 
thereof or indirect powering thereof as the generator or alternator 23 
powers an onboard battery. Many applications will not require the 
generator or alternator 23 and even the signal conditioning and control 
circuitry 24 can be located externally of the coupler 6. Similarly, many 
applications will not require the on board battery, the timing pulse or a 
rotating element. The signal conditioning and control circuitry has a 
memory 25 associated therewith and by means of which initial signals 
instructing the computer may be sent thereto when the coupler is initially 
aligned and positioned within said diskette drive. 
In order to effect a coupling between the read/write head 30 found in a 
diskette drive and an external peripheral device, the head 30 is located 
at a particular track position of what would be the diskette, however in 
contrast to a diskette where a rotating medium would be spinning past the 
head, a data transfer element in this case a read/write element 28, is 
provided by means of which data is transferred to or received from the 
read/write head 30. This read/write element 28 is stationary and in the 
case of inductive coupling the read/write element 28 is in the form of a 
coil. Read/Write element 28 is connected via suitable electrical 
connection indicated as 36 to the signal conditioning and control 
circuitry indicated as 24. In many cases the electrical connection 36 will 
lead directly to an external peripheral device. 
When information is transmitted from the external device to the computer 2 
a modulated electrical current creates a magnetic field in the read/write 
element 28. This field causes an electrical current to be induced in the 
read/write head 30 of the diskette drive which is treated by the 
downstream electronics of the diskette drive as a stream of bits coming 
from a spinning diskette. When transmitting data from the computer to the 
peripheral device 8 the read/write element 28 on the coupler 6 is exposed 
to the modulated electromagnetic field from the diskette drive read/write 
head 30 which behaves as if it is writing to an ordinary diskette. 
This field induces an electrical current in the coupler read/write element 
28 which is then directed to the external device 8. Amplification and 
conditioning of the signal received from the read/write head 30 via the 
read/write element 28 can occur either on the coupler 6 or external 
thereto. 
The read/write element 28 on the coupler 6 can be positioned other than 
directly against the read/write head 30 of the diskette drive as shown in 
FIG. 7. In this case a rotating diskette-like medium indicated as 40 is 
present and is being driven by the diskette drive. The read/write element 
28 when transferring data to the computer 2 will actually write its data 
onto one or more tracks indicated as 42 of the spinning diskette-like 
medium 40 as if it were a normal diskette read/write head. When the data 
thus written is transported to the read/write head 30 of the diskette 
drive by the rotation of the diskette-like medium, the read/write head 
reads the data from the same one or more tracks 42 in the normal manner of 
reading from a diskette. When the computer is transferring data to the 
external device, the read/write head of the diskette will write the data 
onto the diskette-like medium in the normal manner and the read/write 
element 28 of the coupler 6 will read the data from the diskette-like 
medium 40 as the data is carried past the read/write element 28 by 
rotation of the diskette medium 40. 
As previously stated the signal conditioning and control circuitry 24 need 
not be on the coupler 6 and need not include its own power generation or 
battery arrangement. For example this circuitry can be included in the 
external device and be powered thereby. There are advantages to providing 
it directly on the coupler as the external device would not be required to 
supply such functionality. 
The coupler in FIGS. 6 and 7 includes an interface 34 to provide 
appropriate connection with an external peripheral device. The interface 
34 can be an electrical signal for communication by conductive cable or an 
optical signal for communication by optical fiber. 
Returning to FIG. 1 the invention will be described with respect to a 
typical embodiment where the external peripheral device is a hard disk 
drive which is connected to the computer 2 via the diskette drive already 
present in the computer. In such an example the user sacrifices the 
storage of the diskette and enjoys advantages of the hard disk which would 
include faster access time and greater data capacity. These advantages are 
achieved through an installation process which is simple, quick and 
foolproof and requires no special skills. 
When the user first approaches the computer 2 he would if necessary remove 
any diskette that may be in the diskette drive which he wishes to use in 
coupling his hard disk drive to the computer 2. He would then insert the 
coupler 6 into the drive and perform the normal mechanical activation 
procedure following the loading of a diskette, namely the movement of a 
lever or the closing of a door on the diskette drive. The electrical 
connector 10 connects the coupler with the external hard disk drive 10. 
The user would then "re-boot" his computer causing the computer 2 to enter 
a restart mode as if its power switch had just been turned on or the reset 
button had been pressed. Following a restart or reset the central 
processing unit (CPU) of the computer 2 is directed by a program 
permanently resident in read only memory of the computer to retrieve 
another program from a specified track and sector of the diskette drive 
into which the coupler is inserted. 
The CPU therefore looks for a "bootstrap" program on a diskette that may be 
resident in the diskette drive into which the coupler is inserted. The 
coupler signal conditioning and control circuitry 24 would cause a stream 
of bits to be sent to the read/write head 30 of the diskette drive in a 
form that the bits appear to the diskette drive and the CPU to be a 
"bootstrap" program as being read from a spinning disk. In fact the 
"bootstrap" program is really on the external hard disk and the coupler is 
causing the bit pattern which constitutes that program to be induced 
through electromagnetic coupling into the read/write head 30 of the 
diskette drive. Thus the CPU "thinks" it is loading a normal "bootstrap" 
program into memory and once it has loaded the normal amount of data it 
turns control of the computer over to the "bootstrap" program. In this 
case however the "bootstrap" just loaded from the external hard disk 
undertakes the tasks necessary to configure the software and hardware of 
the computer to allow subsequent application programs and operating 
systems to use the external hard disk drive that is connected by the 
coupler 6 essentially as if it were a normal disk drive installed in the 
computer in the normal manner. 
Having thus configured the computer via the special "bootstrap" program the 
hard disk becomes a resource available to all applications and operating 
systems which may be executed in the computer usable essentially as a 
normally installed hard disk. 
In the preferred embodiment data is transferred to and from the diskette 
drive read/write head 30 to the read/write element 28 of the coupler 
through electromagnetic induction. When information is transferred from 
the external device to the computer a modulated electrical current creates 
an magnetic field in the read/write element which is in the form of a 
coil. This field causes an electrical current to be induced in the 
read/write head 30 of the diskette drive which is treated by the 
downstream electronics in the diskette drive as a stream of bits coming 
from a spinning diskette. Other arrangements are possible for forming a 
data transfer link with the read/write head of the diskette drive, as for 
example a capacitive coupling. 
The peripheral device connected via the coupler 6 could be any peripheral 
device including printers, solid state memory, communication ports, 
networks, scanners, other computer instrumentation, monitors, plotters, 
spatial digitizers, control instruments, external audio devices including 
speech recognition, signal analysis, speech synthesis, sound generator, 
and digital audio recording/playback. The peripheral device could be a 
pointing device such as mouse, track ball, joy stick, or knob box. It is 
also noted that a series of peripherals could be attached in the manner 
now carried out using a single computer port. 
The interface 34 could allow connection via a free air radio or optical 
signal as generally shown in FIG. 2 which depicts a wireless transreceiver 
arrangement which connects the coupler 6 with the peripheral device 8. 
The embodiment of FIG. 3 illustrates how two couplers 6 can be used to 
connect two separate personal computers 2 via the diskette drives of the 
personal computers. 
The embodiment of FIG. 4 illustrates how the coupler 6 may be integrated 
with a peripheral device generally indicated as 8a. Thus the electrical 
connection between the coupler and the peripheral device is now completed 
via the integration of the coupler and the external peripheral device. 
The embodiment of FIG. 5 illustrates how the adapter can be used for 
coupling a personal computer into a local area network. 
All the embodiments of FIGS. 1 through 5 recognize that the coupler 6 
renders the read/write head of the diskette drive an input/output port by 
means of which the personal computer 2 can effectively communicate with 
external peripheral devices in many different forms. Depending upon the 
particular application for which the read/write head is rendered a data 
transfer port, certain configurations of the coupler 6 may be preferred. 
The coupler may also render the read/write head of the diskette drive an 
input port only or an output port only. 
In FIG. 1, a separate port 9 is shown which is associated with the 
read/write head of the diskette drive 4. This port would be provided in 
new computers to allow a direct connection to the circuitry within the 
computer associated with the read/write head. Thus, rather than forming a 
coupling via the read/write head the port 9 is wired to the circuitry to 
allow serial data to flow directly to or from a connected peripheral. Such 
a port could utilize the desirable characteristics of the circuitry 
associated with the read/write head. 
Some advantages the coupler and method of the present invention may have 
over other ports that are present on a personal computer or which may be 
installed in a personal computer are as follows: 
Such an interface is almost universal, since most personal computers are 
equipped with removable-media diskette drives. Other types of 
communications ports are much less universally available on all personal 
computers. 
Installation is immediate and convenient. Most ports require the user to 
connect from behind the computer and may require the use of tools to 
remove and attach connectors. Where a suitable port does not exist and a 
circuit board must be installed in the personal computer to provide such 
functionality, then the user is forced to dismantle the computer and 
physically install hardware within the computer's chassis. 
Installation is foolproof, since connecting to the port is a task identical 
to inserting a diskette into the drive, a function that any computer user 
is comfortable with. 
This system provides a higher speed two-way channel than is typically 
available on personal computers. 
This system offers considerable cost savings over alternate methods having 
comparable performance. 
Although preferred embodiments of the invention have been described herein 
in detail it will be appreciated by those skilled in the art that 
variations may be made thereto without departing from the spirit of the 
invention or the scope of the appended claims.