Field of the Invention
[0001] The present invention relates to a light control method, specifically relates to
a flashing light control method and apparatus thereof.
Background of the Invention
[0002] In electrical products, it is necessary to use different flashing lights to represent
different operation situations. In figure 1, a low pulse signal 100 controls a switching
device 104 that makes a light emitting diode 102 flash.
[0003] Typically, there are two methods of generating the low pulse signal 100. One is to
use a program to control a counter in a CPU to output the pulse signals from the general
purpose input/output pins. The pulse signals make the switching devices switch the
light emitting diodes on/off. However, the CPU has to keep working in this method,
which increase the power consumption of the electrical products. Additionally, the
working efficiency of the CPU is reduced because the partial calculation period is
used to generate the pulse signals.
[0004] Another method is to use an oscillation circuit to generate pulse signals with a
fixed period to make the switching device switch the light emitting diodes on/off.
However, an additional oscillation circuit is required in this method, which increase
the cost and the volume of the electrical products. Moreover, the oscillation circuit
can only generate a pulse signal with a fixed period. Therefore, the flashing period
is also fixed, which limits the application range thereof.
[0005] A pulse signal generator inside a CPU is typically used to resolve the problem of
fixed period resulting from use of the oscillation circuit. This pulse signal generator
is used to provide a pulse signal whose period is modulated by the CPU. However, although
this method can resolve the fixed period problem, a pulse signal generator can only
provide a pulse signal. In other words, the number of flashing lights is related to
the number of pulse signal generators inside a CPU. If the number of pulse signal
generators built in a CPU is not enough, an additional pulse signal generator must
be attached to the CPU, which increase the manufacturing cost and the volume of a
electrical product.
Summary of the Invention
[0006] Therefore, the main purpose of the present invention is to provide a flashing light
control method and apparatus thereof to make many lights flash but not increase the
power consumption and volume of a electrical product.
[0007] Another purpose of the present invention is to provide a flashing light control method
and apparatus thereof by using a pulse signal generator to make many lights flash.
[0008] A further purpose of the present invention is to provide a flashing light control
method and apparatus thereof to control the flashing light period without reducing
CPU efficiency.
[0009] Accordingly, the states of the general purpose Input/Output pins of a CPU can determine
whether or not a light is triggered by a pulse signal generated by a pulse signal
generator. The method not only can use a pulse signal generator built in a CPU but
also can use a pulse signal generator independent from a CPU.
Brief Description of the Drawings
[0010] The foregoing aspects and many of the attendant advantages of this invention will
become more readily appreciated and better understood by referencing the following
detailed description, when taken in conjunction with the accompanying drawings, wherein:
Figure 1 is a typical pulse signal for flashing lights;
Figure 2 is a block diagram of a control circuit according to the first embodiment;
Figure 3 is a control circuit diagram according to the block diagram illustrated in
figure 2;
Figure 4 is a block diagram of a control circuit according to the second embodiment;
Figure 5 is a control conditions table for making lights flash; and
Figure 6 is a control conditions table for keeping lights on or off.
Detailed Description of the Preferred Embodiment
[0011] Figure 2 is a block diagram of a control circuit according to the first embodiment.
According to the first embodiment, a CPU 200 with a low pulse generator (LPG) 202
makes lights flash by controling the states of the general purpose Input/Output (GPIO)
pins 210 and thereby selecting which light flahses. The pulse signal generated by
the low pulse generator 202 makes the selected light flash. A pulse signal controller
204 triggers a specific driving circuit in the driving circuitdriving circuit module
206 according to the states of the general purpose Input/Output (GPIO) pins 210 of
the CPU 200. Then, the pulse signal received by the pulse signal controller 204 can
make a specific light in the light module 208 flash through the triggered driving
circuit. The light module is composed of light emitting diodes respectively connected
to corresponding driving circuits.
[0012] Figure 3 is a control circuit diagram according to the block diagram illustrated
in the figure 2. Reference is made to figure 2 and figure 3. A low pulse generator
(LPG) 202 is built in a CPU 200. According to the embodiment, the conductive line
300, 302 and 304 connected with the low pulse generator 202 and the conductive lines
312, 314 and 316 connected with the CPU 200 are respectively connected together to
form three intersections that serve as the three output points S
1, S
2 and S
3 of the pulse signal controller 204.
[0013] When the state of a general purpose Input/Output pin 210 is set in an Input mode,
this pin has a "high" input impedance. When the state of a general purpose Input/Output
pin 210 is set in an output mode, this pin is grounded. For example, when the general
purpose Input/Output pin 306 is set in an Input mode, this pin has a "high" input
impedance. Therefore, the output signal of the output point S
1 of the pulse signal controller 204 is the pulse signal transmitted by the conductive
line 300. Conversely, when the general purpose Input/Output pin 306 is set in an output
mode, this pin is grounded. The output point S
1 of the pulse signal controller 204 is also grounded. Therefore, the pulse signal
transmitted by the conductive line 300 is reduced to a "zero" level state through
the resistance R1. In other words, the output signals of the three output points S
1, S
2 and S
3 can be determined by controlling the states of the corresponding general purpose
Input/Output pins.
[0014] There are three switching devices 318, 320 and 322 in the driving circuit module
206. The three switching devices 318, 320 and 322 are transistors. These switching
devices 318, 320 and 322 are respectively controlled by the three output points S
1, S
2 and S
3. For example, when the output point S
1 is grounded because the corresponding GPIO pin 306 is set in an output mode, the
switching device 318 is in an "off' state because the pulse signal transmitted by
the conductive line 300 is reduced to a "zero" level state through the resistance
R1. Conversely, when the corresponding GPIO pin 306 is set in an "input" mode, this
pin has a "high" input impedance. Through the conductive line 312, this "high" input
impedance makes the output point S
1 output the pulse signal transmitted by the conductive line 300 to switch the switching
device 318. At this time, the corresponding light emitting diode 324 in the light
module 208 flashes according to the switching of the switching device 318.
[0015] When both the GPIO pins 308 and 310 are set in the input mode and the GPIO pin 306
is set in the output mode, the output point S
1 is grounded to turn of the switching device 318, and the output points S
2 and S
3 respectively output the pulse signal transmitted from the conductive lines 302 and
302 to switch the switching devices 320 and 322. At this time, the light emitting
diode 324 is turned off because the switching device is in an "off" state. The light
emitting diodes 326 and 328 flash according to the switching of the switching devices
320 and 322.
[0016] On the other hand, the light emitting diodes can be kept on in the present invention.
In such situation, the LPG 202 is turned off to stop providing the pulse signal. Therefore,
the three output points S
1, S
2 and S
3 of the pulse signal controller 204 are only controlled by the GPIO pins. For example,
when the GPIO pin 306 outputs a "high" level such that the output point S
1 is also in a "high" level, the switching device 318 is kept in an "on" state, thereby
making the LED 324 continuously on.
[0017] Figure 4 is a block diagram of a control circuit according to the second embodiment.
The main difference between the first and second embodiment is that an independent
LPG 220 controlled by a GPIO pin of the CPU 200 is used in the second embodiment to
generate the pulse signal. However, the operation method of the first and second embodiment
is the same.
[0018] Figure 5 is a control conditions table for making light emitting diodes (LEDs) flash.
Reference is made to figure 3 and figure 5 together. For example, the situation described
in number 3 is that the LED 328 flashes and the LEDs 324 and 326 are off. In such
situation, the GPIO pin 310 is set in the input mode and the GPIO pins 306 and 308
are set in the output mode. According to the setting of the pins, the output point
S
1 and S
2 are grounded. Therefore, the switching devices 318 and 320 are turned off. The LED
324 and 326 are turned off. The output point S
3 outputs the pulse signal transmitted by the conductive line 304 to switch the switching
device 322. The LED 328 flahs according to the switch of the switching device 322.
On the other hand, the situation described in number 8 is that the LEDs 324, 326 and
328 are all turned off. In such situation, all of the GPIO pins 306, 308 and 310 of
the CPU 200 are set in the output mode. It is noted that the control condictions described
in figure 5 also can be used in the circuit structure illustrated in figure 4.
[0019] The present invention also can maintain the light emitting diodes in on/off states.
Figure 6 illustrates a control conditions table. For example, the situation described
in number 13 is that the LEDs 326 and 328 are continually on and the LEDs 324 is off.
In this situation, the LPG 202 is turned off to stop the flashing function. The GPIO
pins 308 and 310 are set in the output mode with a high level and the GPIO pin 306
is set in the output mode with a low level. According to the setting of the pins,
the output point S
1 is grounded to turn off the switching device 318. Therefore, the LED 324 is turned
off. The output points S
2 and S
3 output the high level signal to turn on the switching devices 320 and 322. Therefore,
the LEDs 326 and 328 are continually turned on. On the other hand, the situation described
in number 16 is that the LEDs 324, 326 and 328 are all turned off. In this situation,
all GPIO pins 306, 308 and 310 of the CPU 200 are set in the output mode with a low
level. It is noted that the control conditions described in the figure 6 also can
be used in the circuit structure illustrated in the figure 4.
[0020] Accordingly, the states of the general purpose Input/Output pins of a CPU are used
to make a pulse signal controller generate an output signal. This output signal selects
a specific driving circuit. A pulse signal generated by a pulse signal generator triggers
this selected driving circuit, which then makes the corresponding light flash. The
pulse signal generator not only can be a pulse signal generator built in a CPU but
also can be a pulse signal generator located outside a CPU and controlled by a GPIO
pin of a CPU.
[0021] As is understood by a person skilled in the art, the foregoing descriptions of the
preferred embodiment of the present invention are an illustration of the present invention
rather than a limitation thereof. Various modifications and similar arrangements are
included within the spirit and scope of the appended claims. The scope of the claims
should be accorded to the broadest interpretation so as to encompass all such modifications
and similar structures. While a preferred embodiment of the invention has been illustrated
and described, it will be appreciated that various changes can be made therein without
departing from the spirit and scope of the invention.
1. A flashing light control apparatus, comprising:
a central processing unit with a plurality of general purpose input/output pins, wherein
each pin has a specific impedance state;
a pulse signal generator connecting to said central processing unit for generating
a pulse signal;
a driving circuit module with a plurality of driving circuit, wherein said driving
circuit module is connected to said pulse signal generator; and
a light module with a plurality of lights respectively connected to said driving circuits,
wherein said pulse signal triggers said driving circuits to turn on corresponding
lights according to said impedance states of said pins.
2. The apparatus of claim 1, wherein said driving circuits comprises transistors.
3. A flashing light control apparatus, comprising:
a central processing unit with a plurality of general purpose input/output pins and
a pulse signal pin, wherein each of said general purpose input/output pins has a specific
impedance state and said pulse signal pin outputs a pulse signal;
a pulse signal generator connecting to said general purpose input/output pins and
said pulse signal pin;
a driving circuit module with a plurality of driving circuits, wherein said driving
circuit module is connected to said pulse signal generator; and
a light module with a plurality of lights respectively connected to said driving circuits,
wherein said pulse signal triggers said driving circuits to turn on corresponding
lights according to said impedance states of said pins.
4. The apparatus of claim 3, wherein said driving circuits comprise transistors.
5. A flashing light control method for a system, wherein said system comprises a central
processing unit with a plurality of general purpose input/output pins, a pulse signal
pin and a plurality of lights, comprising:
setting the states of said general purpose input/output pins; and
sending pulse signals to trigger lights.
Amended claims in accordance with Rule 86(2) EPC.
1. A flashing light control apparatus, comprising:
a central processing unit (200) with a plurality of general purpose input/output pins
(201), wherein each pin has a specific state;
a pulse signal generator connecting to said central processing unit for generating
a pulse signal;
a pulse signal control unit (204) connecting to said general purpose input/output
pins (210) and said pulse signal generator, said pulse signal control unit has a plurality
of output ends (S1, S2, S3) controlled by said general purpose input/output pins (210) respectively, wherein
said pins (210) control said output ends (S1, S2, S3) to output the special states of pins or said pulse signal;
a driving circuit module (206) with a plurality of driving circuit respectively connected
to corresponding said output ends (S1, S2, S3); and
a light module (208) with a plurality of lights respectively connected to said driving
circuits, wherein said pulse signal triggers said driving circuits to turn on corresponding
lights according to said states of said pins (210).
2. The apparatus of claim 1, wherein said driving circuit comprises a transistor (318,
320, 322) controlled by said corresponding output end (S1, S2, S3).
3. The apparatus of claim 1, wherein said special state is an Input mode with high impedance,
an output mode with a low voltage level or an output mode with a high voltage level.