WO1997032290A1

WO1997032290A1 - Programmable universal remote control

Info

Publication number: WO1997032290A1
Application number: PCT/US1997/002882
Authority: WO
Inventors: Christopher J. Verzulli
Original assignee: U.S. Electronics Components Corp.
Priority date: 1996-03-01
Filing date: 1997-02-27
Publication date: 1997-09-04
Also published as: EP0883869A1; AU1972297A; EP0883869A4

Abstract

A programmable universal remote control for controlling a plurality of electronic devices is provided, including a microprocessor (10), a keyboard matrix (20) coupled to the microprocessor (10) for inputting information into the microprocessor (10) and an output circuit (40) coupled to the microprocessor (10). The microprocessor (10) outputs driving signals to the output circuit (40) for outputting remote control command signals for controlling an electronic device in response to the driving signals. A device look-up table is stored in the microprocessor (10), the look-up table storing device codes identifying respective ones of the plurality of electronic devices and the driving signals associated with the respective electronic devices. An electrically erasable programmable read only memory (EEPROM) (30) is coupled to the microprocessor (10) for storing device codes, whereby the microprocessor accesses the look-up table utilizing the device codes stored in the EEPROM (40) to output a driving signal in response to an input from at least on key of the keyboard matrix (20).

Description

PROGRAMMABLE UNIVERSAL REMOTE CONTROL

BACKGROUND OF THE INVENTION

This invention relates generally to a programmable universal remote

control and more particularly to a programmable universal remote control in which the

codes which are programmed into the remote control are not erased when the batteries

are removed, or the batteries wear out. In addition, the remote control ofthe invention

allows for certain programming techniques while utilizing a minimum amount of

programmable memory, thereby reducing the cost ofthe remote control.

Originally, wireless remote control devices were provided for use with a

specific electronic apparatus. The more common type of remote control utilizes infrared

signals to command the operation of an electronic apparatus such as a television, audio

equipment, video cassette recorder or the like. Thus, the proper infrared remote control

command is associated with a particular button on a key pad ofthe remote control. By

depressing a certain key on the key pad ofthe remote control, the user causes the remote

control to emit an infrared or other signal from the remote control. This remote control

signal is then received by the proper electronic apparatus, the content of the signal is

processed, and the apparatus performs a particular function. However, the remote

control of this type has a number of drawbacks. First, if a user has a number of

electronic devices, each with individual remote controls and associated cornmand

signals, it is necessary for the user to retain each of these remote controls. Thus, since

each electronic unit will have a separate remote control, this is very inconvenient for the

user. Additionally, if the user were to change one piece of equipment, the

remote control which was provided with that equipment would no longer be useful for

the subsequent equipment purchased and used by a user. More specifically, if a user had

a panicular television, with a particular preprogrammed remote control to instruct the

electronic apparatus, upon the purchase of a new television, the old remote control

would be useless, since it would not work with the new television. Additionally, the

new television would require a new remote control, which would be no better than the

old remote control in that it would not reduce the overall number of remote controls

required by a user. Therefore, it would be desirable to provide a single remote control

which allows for the control of a number of different apparatuses, and which is

programmable upon the purchase of a new apparatus.

To overcome these deficiencies, programmable universal remote controls

have-been developed which solve a number of these defects. First, these programmable

remote controls may be programmed with codes to operate a number of different

electronic devices. Additionally, each of these different codes is stored within a single

remote control, thereby allowing a user to utilize only the one remote control to control

a predetermined number of electronic devices.

The first programmable remote controls required the user to '"teach" the

universal programmable remote control the proper codes to implement for each button

depressed. Specifically, this teaching would be performed on the universal remote

control employing a programming sequence. This places the universal remote control

in 'learning" mode. Next, a button on the universal remote control would be depressed, and at the same time a button on the standard remote control included with the apparatus

would be depressed, thereby emitting a signal in accordance with the depressed button,

which would be received by the universal remote control. Therefore, the universal

remote control would "learn" what signal to emit when a particular button were

depressed. In this manner, all of the buttons on a particular remote control can be

implemented on a universal remote control.

Universal remote controls may contain either different sections of a key

pad to run different devices, or a selection button which allows a user to select between

a number of different devices. Thus, after another device was selected, or a different

portion of the universal remote control employed, the same procedure would be

followed for each ofthe remote controls that the user wishes to include on the universal

remote control.

While these programmable "learning" universal remote controls have been

satisfactory, they suffer from a number of shortcomings. First, as noted above, the use

of this type of remote control requires the user to "teach" the universal remote control

each of the individual codes for a particular remote control device. However, it is

possible that a particular remote control device can have a large number of codes which

are required. If a user is required to implement these for a large number of remote

controls, the task can be rather large. Additionally, these codes have typically been

stored in random access memory "RAM" locations in the remote control. However, this

RAM memory only retains its programming while power is supplied thereto. Therefore,

if the user must change the battery in the remote control, or if the battery runs out or is removed, each of these programmed memory modules will be erased. This wouid

require the user then to reenter all of the information previously entered to use the

remote control requiring that the conventional remote controls always be available to

reprogram the universal remote control.

Therefore, it would be beneficial to provide a programmable universal

remote control in which the user did not have to "teach" the universal remote control

each ofthe buttons employed in each ofthe individual remote controls. It would also be

beneficial to provide a programmable universal remote control in which the memory

was retained even after the batteries were removed from the remote control.

In order to solve some of these defic. nc-ies, programmable universal

remote controls have been provided with electrically erasable programmable read only

memory "EEPROM". In this case, all ofthe data and remote control operating program

information is stored in the EEPROM. Therefore, when each of the codes is

programmed into the remote control, these codes are retained by the EEPROM memory

as with all other code to operate the remote control. EEPROM memory retains the

progiamming codes and all other data stored therein even after power has been removed

therefrom. However, in order to retain all ofthe programming codes required to operate

a variety of devices, it is necessary to provide a relatively large amount of EEPROM

memory. Since EEPROM memory is expensive and relatively slow, this greatly

increases the cost ofthe apparatus and decreases the speed ofthe operation ofthe remote

control. Therefore, it would be beneficial to provide a remote control employing a

smaller amount of EEPROM memory, thereby decreasing cost and increasing speed. SUMMARY OF THE INVENTION

Generally speaking, in accordance with the invention, a prograrnmable

universal remote control is provided for operating any number of electronic devices

controlled by a remote control. The remote control is provided with the programming

and operation codes for any number of individual remote control units in its read only

memory "ROM'. Thus, for example, a programmable universal remote control provided

in accordance with the invention would contain a first set of codes for operating a

particular television, a second set of codes for operating a particular VCR, a third set of

codes for operating a second type of television, a fourth code for operating a second type

of VCR and so on. Thus, in order for the user to invoke a certain set of codes for a

certain apparatus, it is only necessary for the user to instruct the remote control which

electronic device the user wishes the remote control to operate.

The programmable universal remote control has the ability to operate any

number of individual devices, and therefore would have in ROM a large number of

program codes for a large number of electronic devices. This functioning is beneficial,

since the ROM can be programmed at the factory before distribution, and ROM does not

lose its information upon removal of power thereto. When the user instructs the

programmable universal remote control as to which devices it wishes the remote control

to operate, the information regarding which device is being controlled is retained in an

EEPROM. This EEPROM may be programmed by the remote control. In addition, these

EEPROMs do not lose their storage capacity upon the removal of electricity thereto. In

this apparatus, it is necessary only to provide a very small EEPROM memory since rather than retaining all of the codes associated with a panicular device which the

programmable universal remote control is to operate, it is only necessary to retain the

device code, which will then implement the predetermined stored operational and

programming codes in the ROM. Thus, the amount of EEPROM memory required is

very small compared to those ofthe prior art, and since EEPROM memory is relatively

expensive, this reduces the cost of production of the remote control.

Accordingly, the invention comprises a programmable universal remote

control for controlling a plurality of electronic devices is provided, comprising a

microprocessor, a keyboard matrix coupled to the microprocessor for inputting

information into the microprocessor and an output circuit coupled to the microprocessor.

The microprocessor outputs driving signals to the output circuit for outputting remote

control command signals for controlling an electronic device in response to the driving

signals. A device code look-up table is stored in the microprocessor, the look-up table

storing device codes identifying respective ones of the plurality of electronic devices

and the driving signals associated with the respective electronic devices. An electrically

erasable programmable read only memory (EEPROM) is coupled to the microprocessor

for storing device codes, whereby the microprocessor accesses the look-up table

utilizing the device codes stored in the EEPROM to output a driving signal in response

to an input from at least one key ofthe keyboard matrix.

In an additional aspect ofthe invention, it is possible to provide a slightly

increased amount of EEPROM memory, thereby allowing for a hybrid operational

remote control. First, the remote control would operate as noted above, whereby a panicular apparatus could be selected, and the remote control would thereafter operate

this apparatus from its preprogrammed ROM. The device codes would be stored in the

EEPROM. while the driving signals would be stored in the ROM placed in the memory

in the factory. In addition, a slightly increased amount of EEPROM would allow a user

to program the remote control with a set of driving and numerical data, in the case where

a new apparatus were produced, and the device codes for this device were not contained

within the ROM in the remote control. In order to keep the EEPROM small, the remote

control might only allow for one or two devices to be programmed in this manner, but

it could certainly allow for any number of devices.

The remote control would also be able to erase the EEPROM so that if a

new product were purchased, and an old one discarded, the device code, and any driver

or numerical data stored in the EEPROM could be changed. Additionally, the EEPROM

would be provided with a structure and method to selectively erase portions of the

EEPROM, thereby allowing for the erasure of a particular device code and associated

driver and numerical data without the loss ofthe other sequences. Since EEPROMs do

not lose their storage capacity upon the removal of electricity thereto, if the batteries are

removed from the remote control, or if for any other reason the electricity fails to be

provided to the EEPROM, they will retain the device codes or associated driver and

numerical data, and therefore a user need not reprogram the remote control each time

the batteries are removed or power is not provided to the EEPROM. Accordingly, it is an object of the invention to provide an improved

programmable universal remote control which is able to operate a number of electronic

devices.

Another object of the invention is to provide an improved programmable

universal remote control which employs a reduced amount of electrically erasable

programmable read only memory, thereby reducing the cost of the apparatus.

A further object ofthe invention is to provide an improved programmable

universal remote control in which the programmed information is retained in memory

even after power is no longer provided to the memory.

A still further object of the invention is to provide an improved

programmable universal remote control which stores device codes in EEPROM

memory, and performs functions stored in ROM memory in response to these stored

device codes.

Yet another object of the invention is to provide an improved

programmable universal remote control which allows a user to enter device codes to

define a particular product to be operated, and also allows a user to enter device codes

and associated driver and numerical data to program the remote control to operate a

particular electronic apparatus not previously contained with the programming codes of

the remote control.

Still other objects and advantages ofthe invention will in part be obvious

and will in part be apparent from the specification and drawings. The invention accordingly comprises the features of construction,

combination of elements, and arrangement of parts which will be exemplified in the

construction hereinafter set forth, and the scope ofthe invention will be indicated in the

claims.

BRIEF DESCRIPTION OF THE DRAWINGS

For a fuller understanding of the invention, reference is had to the

following description taken in connection with the accompanying drawings, in which:

FIG. 1 is a block circuit diagram depicting a particular embodiment ofthe

programmable universal remote control ofthe invention;

FIG. 2 is a flow diagram of the method for entering a program code

sequence into the programmable universal remote control ofthe invention;

FIG. 3 is a flow diagram ofthe method for providing the program code to

the microprocessor ofthe remote control;

FIG. 4 is a flow diagram of the method for having the remote control

execute a particular function;

FIG. 5 is a flow diagram depicting the method for entering specific key

playback data to a remote control constructed in accordance with an alternative

embodiment of the invention; and

FIG. 6 is a flow diagram ofthe method for playback of key data entered

in the steps of FIG. 5. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Reference is first made to FIG. 1 which depicts a block circuit diagram of

the memory and execution circuit employed in the programmable universal remote

control of the invention. As is shown in FIG. 1, a microprocessor 10 is provided for

controlling the functioning of a remote control device. A keyboard matrix 20 provides

inputs to microprocessor 10. An electrically erasable programmable read only memory

("EEPROM") 30 is coupled in two way communication with microprocessor 10. An

infrared output circuit 40 is coupled with microprocessor 10.

As is further shown, microprocessor 10 is provided with a number of

input/output pins P0O-P07 and P 10-P13. As is also shown in FIG. 1, data lines

connected to input/output pins P00-P06 and P10-P13 form keyboard matrix 20. More

specifically, the data lines connected to input/output pins P00-P06 and the data lines

connected to input output pins P10-P13 form four parallel horizontal lines cross each

other forming a grid. At each intersecting portion, an example of such an intersection

portion being shown as 21, a data line input/output from P01 crosses a data line from

input/output P10. Each of these crossing portions 21 is also associated with a particular

key in a keyboard. When a key in the keyboard is depressed, a sensor is set off at the

appropriate crossing portion 21. At that time, data will be received by microprocessor

10 at each input/output pin associated with the crossing portion 21 (P01, P 10 in this

example). Therefore, by determining which two lines have been activated, it is possible

for microprocessor 10 to determine the location of the key being pressed in the keyboard, and therefore the associated key function. Therefore, for example, if portion

21 were depressed, microprocessor 10 would receive information at input/output pin

P01 and input/output pin P1O. Based on this input, the microprocessor functioning

program would determine which key input function, power ON/OFF by way of

example, this combination of input pins was associated with, and would thereafter

implement this function. It should be noted that in order to provide additional keyboard

input, it would only be necessary to provide additional crossing portions 21.

Microprocessor 10 is further provided with a timing circuit 12 comprising

an oscillating crystal 13, first and second capacitors 14 and 15, and ground connection

16. A voltage input 17 is coupled to a voltage source 49 which powers microprocessor

10. Microprocessor 10 includes a data output pin 18 for providing output data to control

the output of infrared output circuit 40. Microprocessor 10 includes a data input pin 19

for receiving information from EEPROM 30, a chip select pin P07 for selecting

EEPROM 30, and a pin connected to ground 16. Microprocessor 10 includes internal

random access memory "RAM" and read only memory "ROM' for storing specific data

as will be discussed below.

As is further shown in FIG. 1, EEPROM 30 comprises a voltage in line

31 coupled with voltage input 17 of microprocessor 10 for powering EEPROM 30 and

a connection to ground 16. A chip select line 32 is connected to microprocessor

input/output pin P07 and it informs EEPROM 30 when it is to be employed to output

a particular piece of data. A clock line 33 and a data in line 34 also couple EEPROM 30

to microprocessor 10. As is shown in FIG. 1, lines 33 and 34 also use data input/output pins P04 and P05 of microprocessor 10. these pins also being used for keyboard matrix

20. The ability to pass these data lines through keyboard matrix 20 reduces the required

number of pins, and also improves the functionability of the system.

When EEPROM 30 is selected by microprocessor 10 by a signal along

Chip Select line 32 output at P07. Lines P04 and P05 of microprocessor 10 will be

transmitted along lines 33 and 34 respectively of EEPROM 30. However, when

EEPROM 30 is not selected by Chip Select line 32, the information contained on lines

P04 and P05 of microprocessor 10 will be addressed between keyboard matrix 20 and

microprocessor 10. When Chip Select line 32 has selected the EEPROM. the clock

along line 33 is enabled and input to EEPROM 30 from microprocessor 10, and a data

stream or data request output of pin P05 of microprocessor 10 will be input into

EEPROM 30 along Data In line 34. The data entering EEPROM 30 through Data In line

34 will prompt EEPROM 30 to output particular requested information through Data

Output line 35. This information will be output from EEPROM 30 through Data Output

line 35 and will be input into microprocessor 10 at data input pin 19. Thus, upon proper

prompting from the microprocessor, EEPROM 30 will provide the requested stored

information to microprocessor 10.

Finally, the remote control circuit is also provided with an infrared output

circuit 40 to produce the remote control command signals to control the electronic

o apparatus. As is also shown in FIG. 1, infrared output circuit 40 includes voltage source

49 disposed in parallel with a capacitor 48. The first end of this parallel combination is

connected through line 50 to ground 16, and is also coupled through light emitting diodes 41. 42, arranged in parallel, to the emitter of a transistor 43. The collector of

transistor 43 and the second end of the parallel combination of voltage source 49 and

capacitor 48 are connected to opposite ends of the parallel combination of first and

second infrared output LEDs 41 and 42. The base of transistor 43 is connected through

a resistor 44 to the collector of a second transistor 45. The emitter of transistor 45 is

coupled with the second end of the parallel combination of voltage source 49 and

capacitor 48, the first end of the parallel combination of infrared output LEDs 41 and

42, and is also connected to ground 16, and through a resistor 47 to voltage input pin 17,

which provides a power source for a microprocessor 10 and EEPROM 30 through

voltage pin 31. The base of transistor 45 is connected to data output pin 18 of

microprocessor 10, and receives driving signals from microprocessor 10 regarding a

required output to be produced by infrared output circuit 40. Voltage source 49 would

comprise a number of batteries required to generate the required output signal from

infrared output signal 40 and infrared output circuit 40 would output a signal in response

to a command from microprocessor 10.

During use, a user first places the voltage source, or batteries, into the

remote control. The RAM stores the identity ofthe apparatus which is to be controlled.

This information is input at keyboard matrix 20 when initializing the remote control

unit. When these batteries are placed into the remote control, if the remote control has

not yet been used by the user, no apparatus code corresponding to the product to be

controlled will be stored within the "RAM" of microprocessor 10 ofthe remote control,

and therefore the remote control will not operate with any particular electronic apparatus. A look-up table having proper driving signals corresponding to infrared

remote control command signals required for each function of a large number of

particular electronic devices is stored in the ROM at the time of manufacture.

Accordingly, a look-up table, which can be accessed by device code, will store a driver

signal for each particular key for each device. Thus, microprocessor 10 of the remote

control contains the codes to operate any number of electronic devices, and the user is

required only to inform microprocessor 10 and the remote control which electronic

devices it wishes to operate. In order to inform the remote control which electronic

devices it wishes to operate, the user will follow the steps, as shown in FIG. 2.

As is shown in FIG. 2, after the power source has been inserted into the

remote control, in order to define a particular electronic apparatus, the user presses a

key, which is defined to allow a user to define an electronic apparatus. In a preferred

embodiment, this would be set up as an "F" key. as is shown in step 2 of FIG. 2.

Pressing the F key, the information is registered by keyboard matrix 20 at a

corresponding crossing point 21 informing microprocessor 10 which key has been

pressed. Pressing F causes microprocessor 10 to begin the process of determining which

apparatus is to be controlled and how it is to be controlled.

In step 3, the user is required to select the type of electronic device which

is being controlled by the remote control. As is shown in FIG. 2, in step 3, the user

selects the device code for a television, but this particular electronic device could be any

electronic device, including, but not limited to, a VCR, stereo or CD player. When the

user presses the television key, the information is registered by keyboard matrix 20 at one of the crossing points 21. which informs microprocessor 10 which key has been

pressed. Next, in step 4, the user then enters a code corresponding to the particular

brand and model of electronic device the user is requiring that the remote control

operate. As is shown in FIG. 2, in a preferred embodiment, the brand and model number

comprises a three digit code. However, this code could comprise any number of digits

or device codes, therefore allowing for any amount of product information to be stored

in the remote control.

After the user has entered this code, microprocessor 10 stores the device

code in RAM, and in step 5, the user again depresses the TV, or appropriate electronic

device key in order to inform microprocessor 10 that the user has completed entering

the code. Then, in step 6, this code is transferred from microprocessor 10 through Data

IN line 34 to EEPROM 30 and is stored therein. To perform this process, Chip Select

pin 32 is placed in the ON position, and the information is entered through Data IN line

34 and is clocked in using Clock line 33. Thus, the appropriate device code information

s is forwarded and stored in EEPROM 30 and is also retained in RAM in microprocessor

10. Finally, in step 7, the device code entry process is completed.

A similar process such as this is performed for each electronic device

required to be controlled by the remote control. Each of these codes are stored in the

proper place in EEPROM 30, thereby providing a bank of information with all the

o device codes of the devices required to be controlled by the remote control.

When these device codes are initially stored in EEPROM 30, as noted

above, the information is first processed by microprocessor 10. Microprocessor 10 contains a specific amount of random access memory (RAM) in which these device

codes are also stored. However, this RAM will not survive the removal of the voltage

source from the remote control. Therefore, while upon initial entry, this memory is

available for use by microprocessor 10, if the voltage source is removed, the RAM

memory will "lose" the codes. Since EEPROM 30 does not lose its storage capability

upon the removal of electricity therefrom, the device codes stored in EEPROM 30 will

not be lost and the codes will only be stored in EEPROM 30 if the voltage source is

depleted, or removed.

Reference is next made to FIG. 3 in connection with FIG. 1 which depicts

the reading of the device code information from EEPROM 30 into the RAM of

microprocessor 10 after the voltage source has been replaced. Specifically, when a new

voltage source is provided, the sequence of steps shown in FIG. 3 takes place

automatically. Specifically, upon the insertion ofthe voltage source, step 61 starts the

process. Next, microprocessor 10 reads the device code information from EEPROM 30

in step 62. Specifically, microprocessor 10 selects EEPROM 30 through chip select pin

32 by providing chip select information on pin P07. Upon selection of this pin, and the

provision of a clock signal along line 33, each of the required device codes is output

from EEPROM 30 through Data Out line 35. This information is transmitted serially

through Data Out line 35 to microprocessor 10 at Data In pin 19. This information is

serially stored in RAM in microprocessor 10 in step 63. After all the necessary

information has been transferred from EEPROM 30 to microprocessor 10, the

information retained in RAM memory in microprocessor 10 will be identical to the information originally programmed into EEPROM 30 and microprocessor 10 by the user

in accordance with steps 1-7. Therefore, if the batteries or other voltage source is

removed from the remote control, and thereafter replaced, even though the RAM in

microprocessor 10 will not hold the device codes, EEPROM 30 will automatically

5 forward this information back to the RAM of microprocessor 10, so that the user is not

required to re-enter each of the device codes each time the batteries or voltage source

is removed from the remote control. Thus, as shown in FIG. 3, these codes are stored

in RAM and can be later used for access to the look-up table stored in ROM containing

the actual driver signals for the output of a remote control command signal in response

o to a particular key selection.

Reference is next made to FIG. 4 which depicts a flow diagram showing

the sequence of required steps followed for depressing a particular key on the keyboard

and having the remote control execute a particular function for a particular electronic

apparatus. As is shown in FIG. 4, at step 71, the sequence is started, and the remote

i5 control awaits an input from keyboard matrix 20. In step 72, a button on keyboard

matrix 20 is depressed, and an input is received at a particular crossing point 21. As

described above, this depression provides information along two pins to microprocessor

10. In step 73, microprocessor 10 determines which key is depressed, and also which

function is desired by the depression of this key. Next, microprocessor 10 looks up the

20 device code for the proper apparatus stored in RAM for the device associated with a

particular desired function in step 74. Therefore, by example, if it were determined that

a record key were depressed in step 73, microprocessor 10 would look up the device code for the VCR in step 74. Next, in step 75. by associating the determination of which

key was depressed in step 73. and the device key of step 74. microprocessor 10 is

directed to a particular location in the look-up table stored in ROM containing all of the

required driver signals for the particular electronic apparatus identified by the device

code stored in RAM. Microprocessor 10 reads from the ROM the appropriate driver

signal for the depressed key to control the identified device. After this particular driver

signal has been determined in step 75, the information is output along output line 18 to

infrared output circuit 40. Next, in step 77, infrared output circuit 40 outputs the proper

infrared remote control command signal for the control of the particular electronic

device. Then, as is shown in FIG. 4, the sequence returns to step 71 , whereby the remote

control awaits another keyboard input.

As is depicted by FIG. 4, by using the device code, and the key depressed

sensor ofthe remote control, microprocessor 10 is able to direct control ofthe electronic

apparatus to a particular memory location in a look-up table contained in read-only

memory (ROM) of microprocessor 10, which is never erased. Thus, the remote control

provided in the present invention can control any number of preprogrammed electronic

devices, and the particular devices chosen for control need only be entered into the

remote control once, these codes being stored in an EEPROM even if the voltage source

is removed from the remote control and the EEPROM memory. By allowing

microprocessor 10 to read the device code information from EEPROM 30, and

thereafter store this device code information in RAM. a call to the EEPROM is not required each time a key on keyboard matrix 20 is depressed, therefore increasing the

speed of the response ofthe remote control.

In an altemative embodiment of the invention, it is possible to provide an

EEPROM with a number of additional memory locations, therefore allowing for the

functioning as described above, and in addition allowing for a user to define an

additional electronic device look-up table in the EEPROM, allowing a user to employ

the remote control with any new electronic devices which were not available at the time

the remote control was produced, and therefore whose device codes would not be

provided in the ROM look-up table in microprocessor 10. Thus, if the additional

EEPROM memory is provided, it is possible to form an additional look-up table to hold

the device codes and associated driver and numerical data for any additional remote

control electronic devices.

The definition of a particular key for an additional electronic device to be

controlled by the remote control is depicted in FIG_; 5. Specifically, the process is started

in step 81, and in step 82 the user depresses a define key in keyboard matrix 20. As

described above, this information is transmitted to microprocessor 10 through the two

lines which cross at cross over point 21 associated with this key. Next, in step 83, the

user depresses a different key, the key for which the user wishes to define the associated

output infrared signal. As above, the key depressed is determined by microprocessor 10.

Next, in step 84, the user enters a two digit driver-type number. This driver number is

the first portion ofthe data required by microprocessor 10 in order to properly output

the proper driver signal when the key is depressed for this user-defined electronic device. Thereafter, in step 85. the user enters the numeric data associated with this kev

when controlling this particular electronic device. This information would be provided

by the producer of the electronic device, or by the producer of the universal remote

control, so that the user could properly define each of the infrared remote control

command signals associated with a particular key. Finally, in step 86, the key that was

depressed, the driver data, and the numerical data are each stored in the EEPROM,

which as noted above, comprises additional memory locations and an additional look-up

table to allow the user to perform this function. It should be noted that any combination

of required program information could be entered in steps 84 and 85 as required by the

remote control.

After this definition of keys and storage of codes and data takes place, the

process ends at step 87. This process may be repeated for each key on the keyboard to

be associated with the new electronic device. Thus, the EEPROM stores each key and

the driver and numerical data associated therewith to define a new electronic device.

This information is stored in the additional look-up table by key so that when a key is

depressed in the keyboard matrix, microprocessor 10 can scan the look-up table stored

in the EEPROM to determine if this key has been specifically defined by the user.

Reference is now made to FIG. 6 which depicts the process by which the

remote control plays back and outputs the proper infrared remote control command

signal when a particular key is depressed for an additional electronic device whose

device codes and associated driver and numerical data have been stored in the additional

look-up table in EEPROM 30 in accordance with the method of FIG. 5. Specifically, the process begins in step 91. and in step 92 a key is depressed by the user. This information

identifying which key has been depressed is transmitted to microprocessor 10 as

described above. In step 93. microprocessor 10 determines which key was depressed,

and in step 94 microprocessor 10 searches the additional look-up table stored in

EEPROM 30 to determine whether this key code has been specifically defined in

EEPROM 30 through the steps of the method depicted in FIG. 5, as discussed above.

This searching is performed, as is noted above, through Chip Select line 32, Clock line

33 and Data In line 34. If the information for defining the depressed key is contained

within EEPROM 30, this information, including the driver arid numerical data, is output

along Data Out line 35, and input into microprocessor 10 through data input pin 19. This

search process is depicted in the choice step 96, in which it is determined whether the

key and associated driver and numerical data is stored in EEPROM 30. During this

search, the depressed key is compared to each ofthe keys for which a definition is stored

in the EEPROM. If the answer is yes and the depressed key is defined in the EEPROM,

the driver data is first output from EEPROM 30 along Data Out line 35 through input

pin 19 in step 97, and thereafter the numerical data from EEPROM 30 is output to

microprocessor 10 in step 98.

Returning to step 96, if the key has not been specifically defined in

EEPROM 30, the default driver signal from the ROM memory of microprocessor 10 is

loaded as described above in the first embodiment, including the loading of driver data

in step 99, and the numerical data in step 100. Thus, if a particular key has not been

specifically defined in the EEPROM, the depressing of that key will cause the remote control to operate as it does in the first embodiment, using the device code and the

lookup table in ROM. Finally, as is shown in step 110. if the key was defined in the

EEPROM. and the driver and numerical data was loaded from the EEPROM. it is

provided through microprocessor 10. and the proper driver signal is provided to infrared

output circuit 40 to control the user defined electronic device. If the key was not defined

by a user, and the driver signal was loaded from ROM, this driver signal is thereafter

provided to infrared circuit 40 to output the preprogrammed infrared remote control

command signal.

Therefore, by provision in this alternative embodiment of an additional

EEPROM amount of memory, the user can employ the functions as noted above with

respect to the first embodiment, and also the additional functionality of being able to

define particular keys to be associated with electronic devices which are not contained

within the ROM look-up table within the remote control microprocessor memory. Since

these user defined datas are stored in the EEPROM, they will not be erased upon the

removal ofthe voltage source therefrom.

Finally, in either of these embodiments, it is possible for a user to replace

any particular portion of data without thereby erasing the rest of the data from the

EEPROM. For example, if a user were using the remote control to control a CD player,

a stereo, a television and a VCR, and the user thereafter were to acquire a new

television, but wishes to employ the remote control to run the original three other

devices in addition to the new television, it would be possible for the user to follow the

steps as noted above for programming in the new television, or for programming the individual keys in the second embodiment, and thereby not disturb the codes stored in

the EEPROM for the other devices. This gives a user additional flexibility and allows

a user to substitute one or more electronic devices while retaining the codes for the other

devices. Thus, the device codes or driver and numerical data need not be reentered for

the devices which are not being changed.

It will thus be seen that the objects set forth above, among those made

apparent from the preceding description, are efficiently attained and, since certain

changes may be made in the above construction without departing from the spirit and

scope ofthe invention, it is intended that all matter contained in the above description

or shown in the accompanying drawings shall be interpreted as illustrative and not in a

limiting sense.

It is also to be understood that the following claims are intended to cover

all of the generic and specific features of the invention herein described and all

statements ofthe scope ofthe invention which, as a matter of language, might be said

to fall therebetween.

Claims

CLAIMSWHAT IS CLAIMED IS:

1. A programmable universal remote control for controlling a plurality

of electronic devices, comprising:

a microprocessor;

a keyboard matrix coupled to said microprocessor for inputting

information into said microprocessor;

an output circuit coupled to said microprocessor, said

microprocessor outputting driving signals to said output circuit for outputting remote

control command signals for controlling an electronic device in response to said driving

signals;

a device code look-up table stored in said microprocessor, said

look-up table storing device codes identifying respective ones of said plurality of

electronic devices and said driving signals associated with said respective electronic

devices; and

an electrically erasable programmable read only memory

(EEPROM) coupled to said microprocessor for storing device codes, whereby said

microprocessor accesses said look-up table utilizing said device codes stored in said

EEPROM to output a driving signal in response to an input from at least one key of said

o keyboard matrix.

2. The remote control of claim 1 , wherein said EEPROM retains said

device codes in the absence of power supplied to said EEPROM.

3. The remote control of claim 1. further comprising a random access

memory (RAM) contained within said microprocessor for storing said device codes.

4. The remote control of claim 3, wherein said EEPROM loads said

device codes into said RAM contained within said microprocessor when power is first

supplied to said EEPROM and said microprocessor.

5. The remote control of claim 4, wherein said EEPROM retains said

device codes in the absence of power supplied to said EEPROM.

6. The remote control of claim 1, further comprising a Clock In line

and a Data In line, each providing an input to said EEPROM, said Clock In line and said

Data In line to said EEPROM each sharing a different physical pin of said

microprocessor with at least one key of said keyboard matrix.

7. The remote control of claim 1, wherein a selected device code

stored in said EEPROM may be replaced by a second device code without disturbing

other device codes stored in said EEPROM.

8. A programmable universal remote control for controlling a plurality

of electronic devices, comprising:

a microprocessor;

a keyboard matrix coupled to said microprocessor for inputting

information into said microprocessor;

an output circuit coupled to said microprocessor, said

microprocessor outputting driving signals to said output circuit for outputting remote control command signals for controlling an electronic device in response to said driving

signals;

a device code look-up table stored in said microprocessor, said

devices; and

an electrically erasable programmable read only memory

(EEPROM) for storing a first set of device codes and for storing a second set of device

codes and associated driver data and numerical data input at said plurality of keys not

stored in said look-up table in said microprocessor, whereby said microprocessor utilizes

said device codes to select a particular one of said driving signals to implement in

response to a key input.

9. The remote control of claim 8, wherein said microprocessor selects

which driving signals to implement in response to said input from said keyboard matrix,

whether said driving signals are stored in said EEPROM, or in said device code look-up

table in said microprocessor.

10. The remote control of claim 8, wherein one of said first set of

device codes or said second set of device codes and associated driver and numerical data

stored in said EEPROM may be altered without affecting other data stored in said

o EEPROM.

11. The remote control of claim 8, wherein said EEPROM retains said

device codes in the absence of power supplied to said EEPROM.

12. A programmable universal remote control, comprising:

a microprocessor;

a first, preprogrammed memory location within said

microprocessor storing device codes; and

a second programmable memory location, operatively coupled to

said microprocessor for storing device codes, said microprocessor utilizing said device

codes to output a driver signal, said second programmable memory location retaining

said device codes in the absence of power supplied to said second programmable

memory location.

13. A method for employing a programmable universal remote control,

comprising the steps of:

providing a read only memory ("ROM"), said ROM storing a look¬

up table comprising a plurality of device codes and at least one driving signal associated

with each device code;

providing a random access memory ("RAM'), said RAM adapted

to store at least one device code;

providing an electrically erasable programmable read only memory

(EEPROM), said EEPROM adapted to store at least one device code;

storing at least one device code in said RAM;

copying said at least one device code from said RAM to said

EEPROM;

reading said device code from said RAM; receiving an external input requesting the performance of a

particular function:

utilizing said device code stored in said RAM to access said driving

signal from said look-up table corresponding to said external input; and

outputting said driving signal.

14. The method of claim 13, further comprising the step of outputting

an infrared remote control command signal in response to said driving signal.

15. A method for employing a programmable universal remote control,

comprising the steps of:

providing a read only memory ("ROM"), said ROM storing a

lookup table comprising a plurality of device codes and at least one driving signal

associated with each device code;

providing a random access memory ("RAM"), said RAM adapted

to store at least one device code;

providing an electrically erasable programmable read only memory

(EEPROM), said EEPROM adapted to store at least one device code;

providing power to said remote control;

automatically copying a device code from said EEPROM to said

RAM upon providing power thereto;

reading said device code from said RAM;

receiving an external input requesting the performance of a

particular function; utilizing said device code stored in said RAM to access said driving

signal from said look-up table corresponding to said extemal input; and

outputting said driving signal.

16. The method of claim 15, further comprising me step of outputting

an infrared remote control command signal in response to said driving signal.

17. A method for employing a programmable universal remote control,

comprising the steps of:

providing a read only memory ("ROM"), said ROM storing a

look-up table comprising a plurality of device codes and at least one driving signal

associated with each device code;

providing a random access memory ("RAM"), said RAM adapted

to store at least one device code;

providing an electrically erasable programmable read only memory

(EEPROM), said EEPROM adapted to store at least one device code;

providing power to said remote control; and

automatically copying said at least one device code from said

EEPROM to said RAM upon the provision of power thereto.