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Description  |
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p BACKGROUND ON THE INVENTION
1. Field of the Invention
This invention relates generally to an audio and/or video electronic
apparatus, such as, a television receiver, a cable converter, video tape
recorder, or video or audio disc player and more particularly is directed
to improvements in such audio and/or video electronic apparatus which may
be controlled remotely, as by a separate remote control transmitter or
commander.
2. Description of the Prior Art
It is well known to provide audio and/or video electronic apparatus, such
as, television receivers and video tape recorders, with respective remote
control transmitters or commanders which are separate or apart from the
actual apparatus and can be manipulated by the user for emitting infrared
or other signals by which the respective television receiver or video tape
recorder may have its operations remotely controlled. In general, the
various manufacturers of the mentioned electronic apparatus employ
different remote control codes for remotely controlling the operations
thereof. Thus, although some remotely controlled television receivers have
been recently provided with a remote control transmitter or commander
capable of also functioning to remotely control an associated video tape
recorder, the desired use of a single remote control transmitter for
remotely controlling a television receiver and a video tape recorder is
possible only if both the television receiver and the video tape recorder
have been produced by the same manufacturer or are otherwise adopted to be
controlled by the remote control codes adopted by the manufacturer of the
remote control transmitter or commander. It will be appreciated that, if a
television receiver and a video tape recorder intended to be remotely
controlled are either produced by different manufacturers or are not
adopted to be controlled by a common set of remote control codes, then the
user is confronted with the troublesome prospect of remotely controlling
the television receiver and the video tape recorder by means of respective
different remote control transmitters or commanders.
Even in those cases where a television receiver and a video tape recorder
are produced by the same manufacturer and provided with a single remote
control transmitter for remotely controlling the operations of both the
television receiver and the video tape recorder, multiple controlling
operations are required in some instances. For example, if the television
receiver is initially conditioned for displaying a broadcast television
picture while the video tape recorder is initially conditioned for
recording the broadcast signal, the user has to effect remote control of
the television receiver for change-over of the input thereto from the
antenna terminal to the terminal connected to the output of the video tape
recorder, and remote control of the user further has to separately effect
the video tape recorder for change-over from its recording mode to its
playback or reproducing mode.
It has further been proposed, for example, as disclosed in detail in U.S.
Pat. No. 4,623,887, and in U.S. Pat. No. 4,626,848, to provide a
reconfigurable remote control transmitter having the ability to learn,
store and repeat the remote control codes from other remote control
transmitters. Thus, in the case where a television receiver and a video
tape recorder are produced by different manufacturers and provided with
respective or separate remote control transmitters which do not employ a
common set of remote control codes, the reconfigurable remote control
transmitter is adapted, in its learning or programming mode, to receive
control signals from the remote control transmitter for the television
receiver, and to store the corresponding remote control codes, and then to
receive control signals from the remote control transmitter for the video
tape recorder and to store the corresponding remote control codes. After
the learning and storing operations have been completed, the
reconfigurable remote control transmitter is ready for use in effecting
remote control of the operations of television receiver and/or video tape
recorder. It will be appreciated that, in order to function in the above
indicated manner, the reconfigurable remote control transmitter according
to the prior art has to include an infrared or other light receiver for
receiving the control signals from the remote control transmitters or
commanders intended for use with the television receiver and the video
tape recorder, respectively. Such infrared or other light receiver
included in the reconfigurable remote control transmitter undesirably
increases the size and the power consumption thereof which is clearly
undesirable in a remote control transmitter intended to be hand-held.
Moreover, when using the reconfigurable remote control transmitter
according to the prior art, individual or separate actuations thereof are
required for controlling operations of the television receiver and of the
video tape recorder, respectively. In other words, operations of the
television receiver and of the video tape recorder cannot be
simultaneously controlled through a single actuation of the reconfigurable
remote control transmitter.
OBJECTS AND SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide an
electronic apparatus which may have its operations remotely controlled by
means of a remote control transmitter or commander other than that
intended for use therewith, and which avoids the above mentioned
disadvantages of the prior art.
More particularly, it is an object of the present invention to provide an
audio and/or video electronic apparatus, such as, a television receiver or
a video tape recorder, which, in a remote control mode, is capable of
having operations thereof controllable by respective remote control codes
in response to the reception of corresponding signals from a remote
control transmitter intended for use with such apparatus, but which may be
alternatively remotely controlled in response to the reception of control
signals from another remote control transmitter intended for use with a
different electronic apparatus.
In accordance with an aspect of this invention, in an electronic apparatus
capable, in a remote control mode, of having operations thereof
controllable by respective first remote control codes in response to the
reception of corresponding signals from a first remote control transmitter
intended for use with such apparatus; there are provided, as integral
parts of the apparatus, nonvolatile memory means, means operative in a
programming or learning mode of the apparatus for writing the first remote
control codes in the nonvolatile memory means in association with
respective second remote control codes for controlling the same operations
as the associated first remote control codes and which are generated in
response to the reception of corresponding control signals from a second
remote control transmitter intended for use with a different electronic
apparatus, and means operative in the remote control mode after the second
remote control codes have been written in the nonvolatile memory means to
respond to the reception of one of the control signals from the second
remote control transmitter by reading out from the nonvolatile memory
means the first remote control code which is associated in the nonvolatile
memory means with the second remote control code corresponding to the
received control signal for controlling the respective operation of the
electronic apparatus in accordance with the read-out first remote code.
In accordance with another aspect of this invention, in the remote control
mode after the second remote control codes have been written in the
nonvolatile memory means in association with the respective first remote
control codes, the operations of the electronic apparatus continue to be
controllable by the respective first remote control codes in response to
the reception of the corresponding control signals from the first remote
control transmitter. For achieving the foregoing mode of operation, read
only memory means desirably have the first remote control codes stored
therein and, in the remote control mode after the second remote control
codes have been written in the nonvolatile memory means in association
with the first remote control codes, said first remote control codes are
selectively read out of the read only memory means for contolling the
operations of the electronic apparatus in response to the reception of the
corresponding control signals from the first remote control transmitter.
The above, and other objects, features and advantages of the invention,
will be apparent in the following detailed description of illustrative
embodiments of the invention when read in connection with the accompanying
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic block diagram illustrating the essential components
of an electronic apparatus according to an embodiment of the present
invention;
FIG. 2 is a flow chart to which reference will be made in explaining the
operation of the apparatus according to the embodiment of the invention
illustrated by FIG. 1; and
FIG. 3 is a diagrammatic view illustrating the manner in which associated
first and second remote control codes are stored in a nonvolatile memory
included in the apparatus of FIG. 1.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Referring to the drawings in detail, and initially to FIG. 1 thereof, it
will be seen that the present invention is there illustrated applied to a
television receiver 20 capable of remote control operation, with only
those elements or components of such receiver which are necessary for
understanding of the present invention being shown schematically. More
particularly, the television receiver 20 is shown to comprise, as an
integral component thereof, a microcomputer 21 for controlling the
operations of the television receiver and which includes a central
processing unit (CPU) 22, a random access memory (RAM) 23 used, for
example, by the CPU 22 during its data processing operations, a read only
memory (ROM) 24 for storing predetermined remote control codes for
controlling respective operations of the television receiver, a
nonvolatile memory 25 which, for example, includes a metal-nitride-oxide
semiconductor (MNOS), and is hereinafter further described in detail,
input/output ports 26, 27, 28 and 29, and a connecting bus 30. The
television receiver 20 is further shown to include a photo electric or
light receiver and encoder 31 which is adapted to receive an infrared or
other control signal SR from a remote control transmitter or commander 32A
or 32B, and which generates a respective remote control code RC to be
supplied through the input/output port 26 to the bus 30 and therethrough
to the CPU 22. The remote control transmitter 32A, which may be intended
for use with the television receiver 20 embodying this invention, and the
remote control transmitter 32B which may be intended for use with another
electronic apparatus, for example, a video tape recorder indicated
schematically at 20', are apart or separate from the television receiver
20 embodying the invention, and may employ different sets of remote
control codes for controlling corresponding operations.
Key-operated switches 33A, 33B,-33N are provided on the television receiver
20 and are selectively manually actuable by a user at the television
receiver for controlling respective functions of the latter. When any one
of the switches 33A, 33B,-33N is closed or turned ON, corresponding key-in
data is supplied through the input port 28 and bus 30 to the CPU 22 which
responds thereto by providing a corresponding control signal for control
of the respective function or operation. For example, the switch 33A may
be used for controlling the power ON and power OFF state of the television
receiver. More specifically, in response to closing of switch 33A, a
control signal is supplied from CPU 22 through bus 30 and port 29 to a
power ON/OFF switch circuit 34 which is operative to change-over the
television receiver 20 between a power ON state and a power OFF state in
response to each successive actuation of key-operated switch 33A. The
key-operated switches 33B and 33C may be used for changing the channel to
which the television receiver is tuned in the upward and downward
directions, respectively. More specifically, each time switch 33B is
closed, the CPU 22 supplies an up signal CH.sub.UP through bus 30 and port
29 to a channel selection microcomputer 35 so that the channel to which
the television receiver is tuned is incrementally changed to the next
higher numbered channel. Similarly, each time the key-operated switch 33C
is actuated or closed, the CPU 22 supplies a down signal CH.sub.DN through
bus 30 and port 29 to the microcomputer 35 for incrementally changing the
channel to which the television receiver is tuned to the next lower
numbered channel. The key-operated switches 33D and 33E may be used for
controlling the volume of the sound or audio issuing from the television
receiver. More specifically, when switch 33D is closed, the CPU 22
supplies an up signal V.sub.up through bus 30 and port 29 to a volume
control circuit 36 for increasing the volume of the sound from the
television receiver. On the other hand, closing of the key-operated switch
33E causes the CPU 22 to supply a down signal V.sub.DN through bus 30 and
port 29 to volume control circuit 36 for decreasing the volume of the
sound from the television receiver.
The key-operated switch 33N is actuable to determine the source of the
video signal to be displayed by the cathode ray tube (CRT) of the
television receiver. More particularly, when the switch 33N is closed, the
CPU 22 supplies a corresponding control signal through bus 30 and port 29
to a video source switching circuit 37 which, in response thereto, selects
either a broadcast video signal TV or a video signal being reproduced or
played back by the video tape recorder 20' to be displayed by the cathode
ray tube (not shown) of the television receiver 20.
The television receiver 20 embodying this invention is further shown to
have a slide switch 38 connected with the input/output port 28 for
selectively establishing a learning or programming mode of the
microcomputer 21. More specifically, when the switch 38 is in its
illustrated OFF position for connection with a power source +B, the
microcomputer 21 is in its normal or remote controllable mode for
controlling the operations of the television receiver 20 either in
response to actuation of the key-operated switches 33A, 33B,-33N, or in
accordance with stored remote control codes in response to infrared
control signals from the remote transmitter 32A ore 32B, as hereinafter
described in detail. On the other hand, when switch 38 is moved to its ON
position so that the connection to the port 28 is grounded, there is
established a learning or programming mode of the microcomputer 21. In
such learning mode, as hereinafter described in detail, first remote
control codes for controlling respective operations of the television
receiver 20 in response to the reception by the receiver and encoder 31 of
corresponding control signals from the remote control transmitter 32A
intended for use with the television receiver 20 are stored or written in
nonvolatile memory 25 in association with respective second remote control
codes for controlling the same operations and which are generated in
response to the reception by the receiver and encoder 31 of corresponding
control signals from the remote control transmitter 32B which is intended
for use with a different electronic apparatus, for example, with the video
tape recorder 20' .
The television receiver 20 according to the illustrated embodiment of the
invention is further shown to include light-emitting diodes 39A and 39B
connected through the input/output port 27 and bus 30 with the CPU 22 and
being selectively supplied with energizing current from the CPU 22 for
indicating when a learning or programming operation is started, and when
such learning or programming operation is terminated.
It will be appreciated that the remote control transmitters 32A and 32B may
be of conventional construction and thus are not shown or described in
detail. For the purposes of this invention, it is sufficient that each of
the transmitters 32A and 32B comprises user-actuated keys for remotely
controlling at least the operations of a television receiver that are
controllable at the receiver 20 by the key-operated switches 33A,
33B,-33N, respectively. Of course, if the transmitter 32B is intended for
use with a video tape recorder, as in the illustrated embodiment, it will
also have user-actuated keys for remotely controlling operations of such
video tape recorder, such as, a record or playback key, a fast-forward
key, a rewind key, a stop key and a pause or stop motion key. In any
event, if the transmitters 32A and 32B are intended for use with
electronic apparatus from different manufacturers, they are likely to
employ different sets of remote control codes. For example, when remote
control transmitter 32A has its keys actuated for remotely controlling
those operations directly controlled by actuation of switches 33A,
33B,-33N, the infrared control signals SR.sub.A received by the receiver
and encoder 31 cause the latter to provide respective first remote control
codes RC1A, RC1B,-RC1N. It is to be noted that such first remote control
codes RC1A, RC1B,-RC1N are also stored at corresponding addresses in the
ROM 24. On the other hand, when remote control transmitter 32B has its
keys actuated for remotely controlling the respective operations, the
infrared control signals SR.sub.B then received by the receiver and
encoder 31 cause the latter to provide respective second remote control
codes RC2A, RC2B,-RC2N.
The operation of the CPU 22 in the above described television receiver 20
according to this invention will now be described with reference to the
flow chart of FIG. 2:
At the start of the control program of the CPU 22, in step 1, it is
determined, on the basis of the signal supplied from switch 38 through the
input/output port 28, whether such switch 38 is in its ON or OFF position,
that is, whether or not the learning mode has been selected for performing
a learning operation. If the learning mode has been established, that is,
if the switch 38 is determined to be ON in step 1, the program preceeds to
step 2 in which it is determined whether or not an infrared control signal
is being received by receiver and encoder 31 from a first remote control
transmitter, for example, from the transmitter 32A intended for use with
the television receiver 20 and which has one of its operation-controlling
keys actuated. Such determination is made on the basis of whether or not a
corresponding remote control code, for example, the code RC1A, is being
delivered from the photo electric receiver and encoder 31. If it is
determined, in step 2, that an infrared control signal SR.sub.A is being
received from the transmitter 32A, the program proceeds to step 3 in which
the corresponding remote control code RC1A supplied from the photo
electric receiver and encoder 31 through the input/output port 26 is
written as a first remote control code at a predetermined address in the
nonvolatile or MNOS memory 25, as shown in FIG. 3. Thereafter, in step 4,
an electric current is supplied for a predetermined period of time through
the port 27 to the light-emitting diode (LED) 39A which is thereby
illuminated as an indication of the start of a learning operation. In
other words, the illumination of the LED 39A indicates that a first remote
control code, that is, a remote control code corresponding to the
reception of a respective control signal from the transmitter 32A has been
written at a predetermined address in the nonvolatile memory 25.
Next, in the learning operation, the remote control transmitter 32A is
replaced by the remote control transmitter 32B and the key of the latter
for controlling the same operation of the television receiver as is
controllable by the remote control code RC1A is actuated. In step 5, it is
determined whether or not an infrared control signal SR.sub.B is being
received by the receiver and encoder 31. If the reception of a control
signal SR.sub.B is detected on the basis of the production of the
corresponding remote control code RC2A by receiver and encoder 31, the
program proceeds to step 6 in which such second remote control code RC2A
is written in association with the corresponding first remote control code
RC1A at a respective predetermined address 25a in the nonvolatile memory
25, as shown in FIG. 3. It will be appreciated that the first and second
remote control codes RC1A and RC2A associated at the address 25a in memory
25 result from the actuations of keys of the remote control transmitters
32A and 32B, respectively, for achieving control of the same operation,
for example, for turning the power ON and OFF, in a television receiver.
After the writing of the second remote control code RC2A in memory 25, the
program proceeds to step 7 in which an electric current is supplied
through the port 27 to the light-emitting diode (LED) 39B for a
predetermined period for indicating the completion of a phase of the
learning operation, that is, the writing in the memory 25 of an associated
pair of first and second remote control codes, for example, the codes RC1A
and RC2A. Upon the extinguishing of the illumination of LED 39B, the
control program returns to step 1 for determining if the learning
operation is to be continued, that is, whether or not the switch 38
remains in its ON position.
With switch 38 remaining in its ON position, the remote control transmitter
32A is returned to a position in operative relationship to the receiver
and encoder 31 and a second user-actuated key of transmitter 32A is
operated to provide another infrared control signal SR.sub.A to the by
receiver and encoder 31 for the repetition of the steps 2, 3 and 4,
whereby, the respective first remote control code RC1B is written at the
predetermined address 25b in memory 25. Then, transmitter 32A is replaced
by transmitter 32B in operative relationship to the receiver and encoder
31, and a user-actuated key of transmitter 32B is operated to provide an
infrared control signal SR.sub.B from transmitter 32B for the repetition
of the previously described steps 5, 6 and 7, as a result of which the
respective second remote control code RC2B is written in association with
the first remote control code RC1B at the address 25b in the nonvolatile
memory 25.
It will be appreciated that, in the learning mode, steps 2, 3 and 4 and
steps 5, 6 and 7 are repeated with reference to infrared control signals
SR.sub.A and SR.sub.B from transmitters 32A and 32B, respectively, until
paired or associated first and second remote control codes have been
written in memory 25 for the various operations of the television receiver
to be controlled.
Although the paired or associated first and second remote control codes
written in the memory 25 are generally for controlling the same operations
of a television receiver, in the illustrated preferred embodiment of the
invention the associated first and second remote control codes RC1N and
RC2N preferably constitute an exception to this general rule. More
specifically, in the case where the television receiver 20 embodying this
invention is connected with the video tape recorder 20', the first remote
control code RC1N resulting from operation of a user-actuated key of the
transmitter 32A is adapted to control the video source switching circuit
37 of the television receiver 20, that is, to select either the broadcast
video signal TV or the video signal being reproduced or played back by the
video tape recorder 20' for display by the cathode ray tube of the
television receiver. On the other hand, the second remote control code
RC2N associated with the first remote control code RC1N results from the
operation of the user-actuated key of the transmitter 32B which controls
the record and playback operations of the video tape recorder 20'.
At the completion of the learning or programming operation, the user
returns switch 38 to its OFF position so that, upon the return to the step
1, the OFF condition of the switch 38 is sensed and the control program
proceeds to the step 8 in which it is determined whether a key-input is
then being obtained from any of the switches 33A-33N. If any such key
input is present, the control program proceeds to step 9 in which a
suitable control signal is supplied from the CPU 22 through port 29 to the
respective one of the circuits 34-37 for controlling the respective
operation of the television receiver. If no key input is detected in step
8 or upon the completion of a television receiver control operation in
step 9, the control program proceeds to step 10 in which it is determined
whether or not an infrared control signal is being received by receiver
and encoder 31 on the basis of whether or not a remote control code RC is
being provided from the receiver and encoder 31. If it is determined, in
step 10, that no infrared control signal is being obtained by receiver and
encoder 31 from the transmitter 32A or 32B the control program returns to
step 1.
However, if it is determined, in step 10, that an infrared control signal
is being received by the receiver and encoder 31, the program moves to
step 11, in which the first remote control codes RC1A, RC1B,-RC1N are read
from the ROM 24 and then compared, in the next step 12, with the remote
control code provided by the receiver and encoder 31 in response to the
infrared control signal received by the latter. If it is determined, in
step 12, that the remote control code provided from the encoder 31 is one
of the first remote control codes read out of the ROM 24, as is the case
when the infrared control signal is from the transmitter 32A intended for
use with the television receiver 20 so that the respective remote control
code is one of the first remote control codes RC1A-RC1N, the CPU 22 is
effective, in the step 13, to provide a suitable control signal through
the port 29 for controlling the operation of the television receiver in
accordance with the first remote control code produced by the receiver and
encoder 31 and, thereafter, the control program returns to step 1.
On the other hand, if it is determined, in step 12, that the remote control
code obtained from the receiver and encoder 31 is not the same as one of
the first remote control codes RC1A-RC1N in the ROM 24, the control
program proceeds to the step 14 in which the second remote control codes
RC2A-RC2N are read from the nonvolatile memory or MNOS 25 and then
compared, in the following step 15, with the remote control code from the
receiver and encoder 31. In other words, in step 15, it is determined
whether or not the remote control code from the receiver and encoder 31 is
equal to any of the second remote control codes RC2A-RC2N read from the
nonvolatile memory 25.
If it is determined, in step 15, that the remote control code being
provided by the receiver and encoder 31 is not one of the second remote
control codes RC2A-RC2N read from the nonvolatile memory 25, then it
follows that the remote control code being provided from the receiver and
encoder 31 results from an infrared control signal from a remote control
transmitter other than the transmitter 32A intended for use with the
television receiver 20 or the transmitter 32B for providing the second
remote control codes that were written in the nonvolatile memory 25 during
the learning operation. In that case, the control program is returned from
step 15 to step 1. However, if it is determined, in step 15, that the
remote control code provided by the receiver and encoder 31 is equal to
one of the second remote control codes RC2A-RC2N read from the nonvolatile
memory 25, the control program proceeds to the step 16 in which there is
read from the memory 25 the one of the first remote control codes
RC1A-RC1N which is associated with the one of the second remote control
codes RC2A-RC2N equal to the remote control code from encoder 31.
Thereafter, in the following step 17, the one of the first remote control
codes RC1A-RC1N read from the nonvolatile memory 25 causes the CPU 22 to
supply a corresponding control signal through the port 29 for controlling
the respective operation of the television receiver 20, and then the
control program returns to step 1.
So long as the switch 38 remains in its OFF position for selecting the
normal or remote control mode of the television receiver 20, the above
described steps 8-17 are repeatedly performed.
It will be appreciated that, in the television receiver 20 in accordance
with the described embodiment of the invention, after a learning operation
for writing in memory 25 the second remote control codes RC2A-RC2N
resulting from the use of the transmitter 32B in association with the
first remote control codes RC1A-RC1N resulting from the use of the
transmitter 32A, the operations of the television receiver can be remotely
controlled either by the remote control transmitter or commander 32A
intended for use with that television receiver 20, or by the remote
control transmitter or commander 32B, for example, intended for use with
the video tape recorder 20' or other electronic apparatus from another
manufacturer and employing a different set of remote control codes. In
other words, when switch 38 is in its OFF position following the described
learning operation for recording the second remote control codes RC2A-RC2N
in the nonvolatile memory 25 in association with the first remote control
codes RC1A-RC1N, the use of the remote control transmitter 32A for the
television receiver 20 in directing an infrared control signal to receiver
and encoder 31 causes the latter to provide a corresponding one of the
first remote control codes RC1A-RC1N and the CPU 22 responds thereto for
providing the respective control signal through the port 29 for effecting
the corresponding controlling operation of the television receiver. On the
other hand, when the remote control transmitter 32B of a manufacturer
different from that which produced the television receiver is used for the
remote control of the latter, the resulting one of the second remote
control codes RC2A-RC2N provided by the receiver and encoder 31 is located
among the second remote control codes written in the nonvolatile memory 25
and the associated one of the first remote control codes RC1A-RC1N is read
out from such memory 25 so that the CPU 22 may similarly respond to such
read out first remote control code for providing the control signal
through port 29 for controlling the respective operation of the television
receiver. As a consequence of the foregoing, it is apparent that, in the
television receiver 20 according to the described embodiment of the
invention, after the learning operation, the remote control opertion of
the television receiver 20 can be effected either by the remote control
transmitter 32A intended for use with such television receiver or by the
remote control transmitter 32B provided for the video tape recorder 20' or
other electronic apparatus from a different manufacturer employing other
remote control codes.
Alternatively, if desired, after the learning operation, that is, after the
second remote control codes RC2A.varies.RC2N have been written in the
nonvolatile memory 25 in association with the first remote control codes
RC1A-RC1N, respectively, the system may be configured so that the remote
control operation is thereafter attainable only be means of the remote
control transmitter 32B to which the second remote control codes
correspond. In such case, of course, the step 13 appearing on the flow
chart of FIG. 2 would be omitted and the control program of the CPU 22
could be otherwise similar to that previously described.
As earlier noted, in the learning operation, it is desirable that the
second remote control code RC2N be made to correspond to the change-over
of the video tape recorder 20' from its recording mode to its playback
mode under the remote control of the transmitter 32B, and that such second
remote control code RC2N be written in the nonvolatile memory 25 in
association with the first remote control code RC1N which is made to
correspond to the change-over of the video source switching circuit 37 to
select the video signal output from the video tape recorder 20' for
display by the cathode ray tube of the television receiver 20. In such
case, only a single key of the remote control transmitter 32B has to be
actuated by the user for simultaneously controlling the television
receiver and the video tape recorder when it is desired to change from a
condition in which the television receiver 20 is diplaying a broadcast TV
picture which is being simultaneously recorded by the associated video
tape recorder 20', to the condition in which the television receiver 20
displays the video or TV picture being played back or reproduced | | |
