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Mobile Phone Patent Abstract
An adapter for a cellular mobile phone unit which converts the unit
to permit simultaneous insertion of a plurality of telephone numbers.
A main circuit board is coupled to a microprocessor of the unit,
which board includes a plurality of number assignment modules, or
NAM's (ROM's), each NAM having its own unique telephone number code.
The NAM's are connected such that fifteen of the sixteen pin-connections
of each NAM are correspondingly and respectively connected in series,
for coupling to the fifteen pin-connections of a plug at one end
of a ribbon cable, the other end of the ribbon cable being coupled
to the microprocessor of the unit via the conventional NAM connection
therefor. Each remaining pin of each NAM, which is not connected
in series, is connected to a unique stop of a multi-position switch,
so that a selected one of the NAM's may be coupled to the microprocessor
in order to change the telephone number from one to another. A secondary
relay printed circuit board may also be provided to allow for remote
switching from one NAM to another. The principles are also applicable
to a personal computer's expansion slots, where a plurality of dedicated
ROM chips may be selectively accessed by the microprocessor via
the same address location.
Mobile Phone Patent Claims
What is claimed is:
1. A method of using a cellular mobile telephone unit, which cellular
mobile phone telephone comprises a microprocessor, comprising:
(a) simultaneously providing at least first and a second distinct
user telephone numbers in a memory means;
(b) selecting one of the at least first and second distinct user
telephone numbers to be used for making an outgoing call based thereon;
(c) said step (b) comprising coupling the selected one of the distinct
user telephone numbers to the microprocessor of the cellular mobile
telephone unit.
2. The method according to claim 1, further comprising repeating
said steps (a), (b) and (c) a plurality of times so as to make an
outgoing call based on the first telephone number and the second
telephone call on another telephone number.
3. The method according to claim 1, wherein said step (b) comprises
making an outgoing call on a first cellular mobile phone system,
and making an outgoing call on another cellular mobile phone system.
4. The method according to claim 1, wherein said step (c) comprises
manually switching the selected distinct telephone number to the
microprocessor of the cellular mobile telephone unit.
5. A method of using a cellular mobile telephone unit, which cellular
mobile telephone unit comprises a microprocessor, comprising:
(a) simultaneously providing at least two distinct user telephone
numbers in a memory means, whereby the microprocessor of the cellular
mobile telephone unit may access any one of the distinct telephone
numbers;
(b) selecting one of the at least two distinct user telephone numbers,
said step of selecting comprising selectively and exclusively coupling
one of the at least two distinct user telephone numbers to the microprocessor;
(c) receiving an incoming call on the selected one of at least
two distinct user telephone numbers;
(d) switching over to another distinct user telephone number, said
step of switching over comprising coupling the microprocessor of
the cellular mobile telephone unit to the memory means storing therein
the representation of said another distinct telephone number, said
step further comprising simultaneously decoupling a portion of the
memory means storing therein the representation of the one distinct
user telephone number previously coupled to the microprocessor during
said step (b); and
(e) receiving an incoming call via said another distinct user telephone
number provided via said step (d).
6. The method according to claim 5, wherein said step (e) comprises
receiving an incoming call via a different cellular mobile phone
system, as compared to the cellular mobile phone system by which
the incoming was received during said step (c).
Mobile Phone Patent Description
BACKGROUND OF THE INVENTION
The present invention is directed to a device for multiplying the
quantity of cellular mobile phone identification call numbers or
telephone numbers for one mobile phone unit. Cellular mobile phones
are typically mounted in an automobile, truck, van or the like,
allowing access to fixed-wire telephone systems, as well as other
mobile phones, whereby a mobile phone user may call a fixed land-based
phone or another mobile phone.
Under present conditions, the cellular mobile phone system is divided
into a plurality of cells or grids defined by stationary transmitter-receiver
stations, each of which is connected to a switching station connecting
the cell or grid to the land-based, fixed-wire telephone system.
Each cell or grid is designed to allow each mobile phone access
to the land-based phone system, or to allow a land-based or mobile
phone access to another mobile phone, according to a principle in
which that cell that receives the transmitting and/or receiving
signal from a mobile phone or mobile phones is that cell which is
made operative for transmitting and/or receiving the call. Thus,
for example, when a mobile phone subscriber attempts to make a phone
call to another mobile phone, or a land-based phone, that call which
receives the strongest signal from the transmitter of that particular
mobile phone is the one made operative for connection to the phone
being called. If, after connection or during the initialization
of the call, the calling mobile phone travels beyond the effective
range of the cell originally handling the call, another cell which
receives the signal stronger than the original cell, receives the
transmitting signal from the calling mobile phone, and an automatic
system transfer from the first cell to the second cell occurs. Thus,
during the process of calling, and during the call itself, whenever
the mobile phone transfers from the effective range of a first cell
to the effective range of a second cell, the second cell takes over
from the first cell. This may occur many times, depending upon the
distance the mobile phone unit travels during the telephone call,
and depending upon the number of effective cell zones through which
the phone may travel.
Each mobile unit, which is comprised of a transmitter-receiver
(commonly referred to as a transceiver), includes a call-channel
selector which controls a frequency synthesizer to span the available
call-channel frequencies and, in combination with a microprocessor,
selects that call-channel which is received the strongest in order
to select the cell closest to the mobile unit. Each mobile phone
has its own unique telephone or use number by which it may be accessed
by another mobile phone or land-based mobile phone. With presently
known and used systems, each mobile phone is allowed only one such
telephone number. This unique number is included on a ROM chip addressed
by the microprocessor of the mobile unit. However, because only
one user number is possible for each mobile unit, the owner of such
mobile unit is restricted to only one mobile telephone service.
Since each mobile phone unit can presently include only one telephone
or number, this limits the range of use of the mobile unit, and
prevents the possibility of using more than one cellular phone company,
thus, taking advantage of different time rates and access rates.
If a mobile unit could have a pair of telephone numbers, one telephone
number for a first telephone company, and a second telephone number
for a second telephone company, it is possible to use each phone
company at those times when their rates are the lowest, in order
to save money. For example, if the first telephone company offers
lower rates at night, while the second telephone company offers
lower rates during the day, a mobile unit having two telephone numbers
could use the first telephone company's system at night, and use
the second telephone company's system during the day, at considerable
savings.
Further savings are achieved when a mobile unit extends beyond
its home area. Typically, when a mobile unit goes beyond the defined
radius of its home base (defined by the telephone company), they
are charged an additional fee, called the "transit fee,"
for accessing a telephone company in the new region, regardless
of whether it is the user-subscribed telephone company. Thus, if
one were able to have two telephone numbers for the same mobile
unit, the first telephone number could be used for the home-based
telephone system, while the second telephone number could be used
for another telephone system, or another system outside the same
home-based area, when the mobile unit extends beyond the home region.
Under present conditions, when a user wishes to transfer from his
subscribed system to a competitor's system to achieve a better connection
or complete a call outside his home area, roaming fees are also
charged the customer when he uses another company's system. This
roaming is usually achieved by an "A/B" switch, which
switches over from even channel frequencies of the home company
to the odd channel frequencies of the other company. In many cities
and regions, however, it is not possible to access a second telephone
company. Therefore, in addition to providing potential economical
savings by having more than one telephone number for each mobile
unit, it is also possible to make calls which, in certain situations,
have been impossible. Further, if more than one telephone number
could be used for each mobile unit, and each mobile unit could subscribe
to more than one telephone company, in the event a telephone call
made on one system was a poor connection, the user may readily transfer
to the other system where, more often than not, the call would be
a clearer connection. Also, by having more than one telephone number,
each mobile unit could have one telephone number for outgoing calls
only, and have the second telephone number for incoming calls only.
This could be beneficial in limousines, emergency vehicles (such
as ambulances), security vehicles, and the like. Further, by having
more than one telephone number, one may have a separate telephone
number for a frequently visited area, such as for a salesman's territory
or a truck driver's route, where the user would have one telephone
number for use in the area frequently visited. In this case, the
user could avoid long distance costs, as well as roaming charges
and transit fees.
SUMMARY OF THE INVENTION
It is, therefore, the primary objective of the present invention
to provide an adapter for a conventional cellular mobile phone unit,
which allows conversion of one telephone number to a plurality of
telephone numbers, whereby each mobile unit may incorporate therein
a plurality of identifying or telephone numbers, each having access
to a telephone system and each of which may be accessed by a telephone.
It is another objective of the present invention to provide such
a conversion by providing a plurality of number assignment modules,
each of which has its own unique telephone number, and each of which
may be uniquely coupled to the microprocessor of the mobile unit
by a selection switch.
It is yet another objective of the present invention to provide
such a conversion of a conventional cellular mobile phone unit to
include a plurality of telephone numbers, such that the switching
from one telephone number to another may be achieved easily and
readily by a remote switching adjunct, so that the user of the mobile
phone may transfer readily and easily from one telephone number
to another at a location within the vehicle a distance away from
the mobile unit.
It is still another objective of the present invention to provide
an adapter for a conventional cellular mobile telephone unit that
is easily connected to the NAM connection of the conventional unit
in an easy and fast manner, whereby the plurality of NAM's replace
the one fixed NAM provided with the conventional mobile unit.
Toward these and other ends, the adapter for a conventional cellular
mobile phone unit includes a housing in which is mounted a main
printed circuit board upon which are provided, in the preferred
embodiment, four ROM's or Number Assignment Modules (NAM's), each
of which has its unique telephone number by which the user of the
system may make outgoing calls, and to which outside calls may be
made, thus converting the one-telephone number conventional mobile
unit to a mobile unit having a plurality of telephone numbers. The
four ROM's are provided on the main circuit board, such that 15
of the 16 pin connections of each ROM are respectively connected
in series, with one of the pins--the 15th pin--being left free for
connection to a stop of a rotary switch. Each of the series-connected
pins of the ROM's is, in turn, respectively coupled to a 16-pin
jack at one end of a ribbon cable, with the pin 15 of the ROM's
being selectively coupled to pin 15 of the jack via the rotary switch,
whereby any of the ROM's may be activated by the rotary switch for
connection to the microprocessor of the cellular mobile phone unit.
The rotary switch is a 4-position rotary switch, each position of
which corresponds to a different one of the ROM's, to thereby select
the ROM that is to be connected to the microprocessor of the mobile
phone unit, to thereby allow the change of the telephone number
of that unit. The other end of the ribbon cable, to which the ROM's
are connected, is coupled to the microprocessor, at that location
to which the conventional ROM has been provided with the unit and
upon which has been burned the unique telephone number originally
provided the unit.
The rotary switch itself is mounted by the housing, such that the
toggle thereof extends outward from the housing for easy access
by the user of the device. In a second embodiment of the invention,
the rotary switch is provided at the end of a long cable to allow
for remote switching between the ROM's, so that the user of the
mobile telephone system may switch in his regularly-seated position
in the vehicle. The long cable is connected at its other end to
a secondary printed circuit board also contained within the housing
and operatively coupled to the main printed circuit board. The secondary
printed circuit board includes a pair of relays, a single-pole double-throw
switch, and a double-pole double-throw switch, which switches are
mounted in series and operatively coupled to the rotary switch at
the other end of the lead cable by three distinct current paths,
so that four possible states of the output of the secondary printed
circuit board may be achieved in order to activate each of the four
ROM's on the main circuit board. A pair of diodes are also provided
to determine the flow of current in order to achieve the four possible
different states of the output of the secondary printed circuit
board. The present invention may be readily converted from the trunk-mounted
version, in which the rotary switch is mounted directly on the housing,
to the remote version, in which the remote cable with the rotary
switch at one end thereof is used for remote switching between ROM's.
The present invention is also applicable to any microprocessor
accessing memory, such that there is a need for switching over from
one dedicated ROM chip or the like, to another dedicated ROM chip,
such as may occur in a personal computer where dedicated ROM chips
are coupled to the microprocessor via an expansion slot of the personal
computer. Each dedicated ROM chip may be selectively connected to
the microprocessor for performing its own unique dedicated function.
Thus, the effective capacity of the memory of the personal computer
may be increased considerably, since the hexidecimal address location
of each of the plurality of ROM's associated with the expansion
slot is the same, with the switch of the present invention determining
which dedicated ROM is to be coupled to the microprocessor.
BRIEF DESCRIPTION OF THE DRAWING
The invention will be more readily understood with reference to
the accompanying drawing, wherein:
FIG. 1 is a block diagram showing the functional elements of a
conventional cellular mobile phone unit to which is coupled the
main circuit board of the present invention incorporating thereon
a plurality of number assignment modules of the present invention;
FIG. 2 is a schematic view of the main circuit board of the present
invention showing the interconnection of the pins of the plurality
of number assignment modules, and the interconnections between the
number assignment modules and a rotary switch and plug at one end
of a coupling cable of the present invention; and
FIG. 3 is a schematic view of the remote circuit board of the present
invention for remotely switching the main circuit board of FIG.
2 at location remote from the housing mounting the main circuit
board, in order to switch from one number assignment module to another
number assignment module while seated in the vehicle.
FIG. 4 is a schematic view showing a modification of the remote
circuitry of FIG. 3 for eight possible telephone numbers.
DETAILED DESCRIPTION
Referring now to the drawings in greater detail, and FIG. 1 in
particular, for now, a block diagram of the essential components
of a cellular mobile phone unit incorporating the adapter of the
present invention is shown. The mobile unit is indicated generally
by reference number 10, and includes a transceiver having a receiver
12 and transmitter 14 for communication with the cells of a cell-grid
structure of a cellular mobile phone system. The receiver 12 receives
radio signals from the individual cells which are then detected
by a signal detecter 16 for inputting into a microprocessor of the
unit 18. Through the microprocessor 18 and receiver 12, the call-channel
selector 20 will continuously receive the signals from the receiver
12 and select the strongest signal received, as controlled by the
microprocessor 18. A frequency synthesizer 22 will lock in on that
strongest signal, as controlled by the call-channel selector 20.
The frequency synthesizer 22 will also determine the channel in
which a transmitter will send out signals. Thus, both the receiver
and transmitter will lock into the appropriate call channel of the
cell that is closest to the mobile unit 10, and/or the strongest
signal received by the mobile unit 10.
For determining the duplex-communication channel, there is provided
a channel-number detector demodulator 24 which receives the information
from receiver 12, indicating the available duplex channel for the
cell of which the call channel selector 22 has locked in. This duplex
channel is stored in storage register 26, which is coupled to speech-channel
selector 28, which is controlled by microprocessor 18, which controls
frequency synthesizer 22 for locking in the duplex-communication
channel open for that particular cell unit from which the strongest
signals are received. The description up to this point describes
that which is conventional in the art.
Associated with the microprocessor 18 are a plurality of memory
locations, indicated generally by reference numerals 30, 32, 34
and 36. Each memory location 30 through 36 is a distinct and separate
ROM chip, such as EPROM, upon which is burned a unique telephone
or user number. The four ROM's 30 through 36 replace the one ROM
in general use in conventional cellular mobile phone systems. The
four ROM's provide for four different telephone numbers to which,
and from which, the mobile unit 10 provides access. Hithertofore,
the single ROM (commonly referred to as a number assignment module--NAM)
was used, by which only one telephone number could be assigned to
each mobile phone unit. According to the present invention, each
mobile phone unit may be converted so that it can have a multitude
of unique telephone numbers, with each number providing separate
access to a telephone company and associate uses. It is understood
that, although four ROM's 30 through 36 have been shown in FIG.
1, any number of such ROM's may be used to provide a multiplicity
of separate and distinct telephone numbers for each mobile phone
unit.
Referring now to FIG. 2, a schematic diagram is shown indicating
the connection of the four ROM's 30 through 36 to the microprocessor
18, allowing for a multitude of telephone numbers for each individual
cellular unit. The four ROM's 30 through 36 are arranged in parallel
and are coupled such that the corresponding pins of each ROM are
connected in series to the corresponding pins of each other ROM,
as clearly shown in FIG. 2, except for pin 15 in each ROM, which
pin 15 is used for connection to a switch, indicated generally by
40. Each of the corresponding and series-connected pins are, in
turn, coupled to corresponding pins of a 16-pin plug at one end
of a conductor ribbon cable for connecting the ROM's to the microprocessor.
The 16-pin plug, indicated generally by reference numeral 42, corresponds
to the 16 pins of each of the four ROM's connected in series, as
described above, with each fifteenth pin 15, 15', 15", 15"'
thereof being connected to common lead 44 of the switch 40. A capacitor
67 may also be provided between pins 1 and 16 to prevent the arcing
thereof. The switch 40 is a 4-position rotary switch, with each
switch position coupling the 16-pin plug 42 to one of the ROM's
via the free, or non-coupled, pin of each ROM. In the switch position
shown in FIG. 2, the switch 40 would connect ROM 30 to the microprocessor
18, since pin 15 thereof is coupled to pin 17 of the 16-pin dip
plug 42. For the switch position 46, the ROM 32 would be coupled
to the microprocessor, while positions 48 and 50 would couple ROM's
34 and 36 to the microprocessor, respectively. The rotary switch
40 is a standard rotary switch.
In the preferred embodiment, the ROM's 30 through 36 are provided
on a separate, main printed circuit board, in a housing enclosing
both the ROM's ROM card, and associated circuitry in a coventional
manner. The rotary switch 40 is typically connected to the main
printed circuit card via a 5-prong male connector on the main printed
circuit board, with the rotary switch being coupled to the male
connector via a corresponding female connector, in a well-known
manner. Four of the prongs would correspond to the four lines 45,
46, 48 and 50, which is the common line to pin 17 of the plug 42.
In the preferred embodiment, the rotary switch, main printed circuit
board, associated circuitry thereon, and the connectors therefor,
are enclosed in a single unitary housing having an appropriate cut-out
for the extension therethrough of a 16-lead ribbon cable, for subsequent
coupling of the plug 42 to the NAM input associated with the microprocessor
18. The embodiment shown in FIG. 2 is what is termed a "trunk
mounted" version of the invention, in which the housing, and
the associated circuitry, are mounted to the main frame of the cellular
phone unit, with the toggle of the switch 40 extending outwardly
from the housing for access thereto by the user of the phone, for
changing over from one ROM to another, to thereby change from one
telephone number to another.
In a second embodiment of the invention, use is made of a remote
switching device for replacing the housing-mounted switch 40. This
remote switching device allows for the switching from one ROM to
another, from a remote distance, for example, by a driver situated
behind the steering wheel of an automobile, which would allow him
to switch from one number to another from his regularly-seated position
in the automobile. This embodiment is illustrated in FIG. 3. In
this embodiment, a remote 4-position rotary switch 50' is provided,
which is connected to one end of a long, 4-lead wire cable. Each
of the four positions of the rotary switch 50', like rotary switch
40, is used to couple one of the ROM's to the microprocessor 18.
The rotary position indicated by reference numeral 52 is that position
in which rotary switch 50 shuts off power from a 12-volt source
to the relays discussed below. The rotary positions 54, 56 and 58
are, respectively, connected to lead wires 60, 62 and 64, the ends
of which are coupled to a switching circuit incorporating a pair
of series-connected relays 70 and 72, with each being grounded along
line 74. Each relay 70 and 72 is associated with a switch 76 and
78, respectively, with switch 76 being a double-pole double-throw
switch, while switch 78 is a single-pole double-throw switch. The
switch 76 includes contacts 80, 82, 84 and 86, while the switch
78 includes contacts 88 and 90. Mounted in parallel to the relays
70 and 72 are a pair of oppositely-disposed diodes 92 and 94, interconnected
by lead line 96 which is coupled to the rotary position contact
58. Each of the relays 70 and 72 is connected to the rotary position
contacts 54 and 56, as clearly shown in the drawing, along lines
60 and 62. It may, therefore, be seen that the rotary switch 50
determines four separate and distinct combinations of states for
the switches 76 and 78, by the series connection of an arm 98 of
switch 76 to a contact 88 of the switch 78, and series connection
of an arm 102 of the switch 76 to contact 90 of the switch 78. Arm
106 of the switch 78 is coupled to common, which is in turn, coupled
to pin 15 of the jack 42 coupling the ROM's to the microprocessor.
Each of the contacts 80, 82, 84 and 86 of the switch 76 is connected
to one of the ROM's 30, 32, 34 and 36. Thus, it may be seen that,
depending on the relative positions of the arms of the switches
76 and 78, one of the ROM's is connected to the jack 42 for coupling
to the microprocessor of the mobile phone unit to connect the unique
telephone number thereto.
When the rotary switch 50' is in the first position, with the upper
arm thereof contacting the contact 52 thereof, the switches 76 and
78 are in position as shown in FIG. 3. That is, the arms 98 and
102 contact the stops 80 and 84 of the switch 76, while the arm
106 contacts the stop 88, since there is no power supplied to the
secondary unit, thereby de-energizing the relays 70 and 72, causing
the spring-biassing of the arms of the switches to assume their
normal, unpowered position shown in FIG. 3. In this state, as shown
in FIG. 3, ROM or NAM 32 is powered and coupled to the microprocessor.
In the second position of the rotary switch, when the arm contacts
the stop 54 thereof, the current flows through the line 60 to energize
relay 70 only. Diode 92 prevents current from flowing to and energizing
relay 72. In this position, the arm 106 is in its position as shown
in FIG. 3, while the switch 76 is energized, such that the arms
98 and 102 contact the stops 82 and 86 respectively, to thereby
energize the ROM 34, since the arm 98 contacts the stop 82 of switch
76. In the third position of the rotary switch, when the arm contacts
the stop 56, current flows through the line 62, and from there to
the relay 72, to energize this relay to move the arm from the position
shown in FIG. 3, such that the arm 106 contacts the stop 90 thereof.
The diode 94 prevents current from flowing to the relay 86 in combination
with the grounded line 74. In this position, the switch 76 is that
shown in FIG. 3, while the arm 106 contacts the stop 90, to thereby
energize and couple ROM 36 to the microprocessor. In the fourth
position of the rotary switch, when the arm contacts the stop 58,
current flows through line 64, and branches to each of the diodes
92 and 94, and from there to each of the relays 70 and 72, to energize
both of them. Thus, each of the arms 98, 102 and 106 are in their
oppositely-disposed position as compared to those shown in FIG.
3, where the arm 106 contacts the stop 90, while the arms 98 and
102 contact the stops 82 and 86 respectively, to thereby complete
the connection for energizing ROM 38 and coupling it to the microprocessor
through the plug 42.
It is to be noted that each of the lines running from the contacts
80, 82, 84 and 86 are connected to pin 15 of the respective ROM
32, 34, 36 and 38, in the manner similarly shown and described for
the first embodiment shown in FIG. 2. The connection between the
contacts and the pin is achieved via a 5-pin connection, in the
same manner as previously described in the embodiment of FIG. 2.
The remote cable connecting the switch 50' to the housing mounting
the main circuit board on which the ROM's are mounted, and the secondary
board upon which are mounted the switches 76 and 78 and associated
relays and diodes, is preferably 17 feet in length to allow adequate
remote control thereby.
It is clear that more or less than four ROM's may be used to provide
greater or fewer telephone numbers for the single cellular mobile
phone unit. If less than four ROM's were to be used, the same general
switching arrangement may be used as above-described for the trunk-mounted
version or for the remote switching version. If more than four ROM's
are to be used than in the trunk-mounted version, a rotary switch
having as many stop positions as the number of ROM's would be used.
For the remote switching version, the same general principles as
that shown in FIG. 3 would be used. If, for example, eight ROM's
were to be used, the switch 76 would be replaced by the 8-position
switch 99 having four movable arms, while the switch 78 would be
replaced by a double-pole double-throw switch 81, and the rest of
the circuitry shown in FIG. 3 would be exactly the same, except
the outputs from the 8-contact switch would each be connected to
one of the eight ROM's. An additional single-pole double-throw switch
circuit is provided, which would be controlled manually by a switch
adjacent an 8-position rotary switch for the eight ROM's as shown
in FIG. 4. Thus, any one of the eight ROM's may be connected to
the microprocessor, according to the same general principles as
above-described, where there are four ROM's provided.
It is also to be understood that the present invention has relevance
and use for any microprocessor, whether it is for a cellular mobile
phone unit, or a microprocessor of a personal computer. For example,
in a personal computer, when it is desired to add additional memory
capacity to the computer via an expansion slot, the concept of the
present invention may also be used, where each of the ROM's 30,
32, 34 and 36 would be a dedicated ROM to perform a specified function,
whether it is for the control of an electromechanical means by the
computer, and the like. The only difference, according to the two
different uses, would be the information burned into the ROM's for
their dedicated use. Thus, according to the principle of the present
invention, when used with a personal computer's expansion slot and
coupled to the microprocessor thereof, since the addressing locations
of each of the ROM's in the expansion slot would be identical, by
simply switching from one to another, the dedicated software therein
may be changed, thereby effectively increasing the memory storage
of the computer. By simply switching from one ROM to the other,
the dedicated program may be altered without sacrificing addressing
locations of the microprocessor of the personal computer.
While this invention has been disclosed for use with ROM's clearly
one could use PROM's, EPROM's and EEPROM's, and while specific embodiments
of the invention have been shown and described, it is to be understood
that numerous changes and modifications may be made therein without
departing from the scope, spirit and intent of the invention, as
set out in the appended claims.
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