JP2000141626A - Electronic apparatus and method for supplying power therein - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize power saving as much as possible in a stand-by condition. SOLUTION: There is disclosed an electronic apparatus comprising a control unit 1 having at least a CPU 2, a RAM and an input/output port 4 and a ROM 7 storing a control program which is executed by the CPU 2. The electronic apparatus further comprises a power source circuit 6 for supplying an electric power to each section in the apparatus and a switch circuit 21 for turning on or off the supplying of the power to the ROM 7 from the power source circuit 6. Upon an instruction for power-off, the control program stored in the ROM 7 is transmitted to the RAM 2. After the transmission is completed, the power supplying to the sections except the control unit 1 is turned off by the switch circuit 21, then the CPU 2 executes the control program stored in the RAM 3 by maintaining the supplying of the power to the control unit 1. As a result, for example, an operation of calibration of a head temperature sensor 17 or lowering of a clock frequency of the control unit 1 is executed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to at least a CPU
And a control unit having a RAM, an input / output port, and a memory storing a control program to be executed by the CPU. The present invention relates to a supply control method.

[0002]

2. Description of the Related Art When an AC plug or the like is connected to a power outlet of an electronic device such as a television device or a computer device, even if the power switch of the device or device is turned off, the circuit is not connected to the circuit. Some are partially powered. In such a device, the power of the device can be turned on or off using, for example, a remote controller using infrared rays.

[0003]

In the case where power is always supplied to a part of the apparatus or device simply by being connected to the AC outlet, the power consumption becomes a problem. That is, it is rare for a television device, a video device, or a computer device to disconnect the AC plug from the AC outlet one by one when not in use, and in most cases, these devices remain connected to the AC power supply. . Therefore, with the increase in awareness of environmental issues in recent years, the problem of wasteful power consumption in such electronic devices has become apparent.

SUMMARY OF THE INVENTION The present invention has been made in view of the above conventional example, and has as its object to provide an electronic device and a power supply control method in the device, which realize further power saving in a standby state.

Another object of the present invention is to transfer a control program to be executed in a standby state from a memory in which power supply is cut off to a RAM in a control unit, and to supply power to the control unit only in a standby state in an electronic device. An object of the present invention is to provide an electronic device that performs power supply control and a power supply control method in the device.

[0006] It is another object of the present invention to provide a system in a standby state.
An object of the present invention is to provide an electronic device and a power supply control method in the device, in which power consumption is suppressed and a standby time is effectively used by executing processing desirably performed in a steady state.

Another object of the present invention is to reduce the frequency of a clock signal supplied to a control unit in a standby state, thereby further reducing power consumption in the standby state, and to control power supply in the electronic apparatus. It is to provide a method.

[0008]

In order to achieve the above object, an electronic apparatus according to the present invention has the following arrangement. That is, a control unit having at least a CPU, a RAM, and an input / output port, and an electronic device having a memory storing a control program executed by the CPU, and a power supply unit for supplying power to each unit of the electronic device. A switch circuit for turning on / off the power supply from the power supply unit to a unit other than the control unit; a transfer unit for transferring a control program stored in the memory to the RAM in response to a power-off instruction; Power transfer control means for controlling the power supply to other than the control unit to be turned off by the switch circuit after the transfer by the means, and the power supply to other than the control unit is turned off by the power supply off control means. Then, while the power supply to the control unit is maintained, the data is stored in the RAM by the CPU. Characterized in that to execute the control program.

In order to achieve the above object, a power supply control method for an electronic device according to the present invention includes the following steps. That is, a power supply control method for an electronic device having at least a control unit having a CPU, a RAM, and an input / output port, and a memory storing a control program executed by the CPU, wherein the power supply control unit executes the power supply control. Transferring a control program stored in the electronic device to the RAM; and, after the transfer in the transfer step, turning off power supply from a power supply unit that supplies power to each unit of the electronic device to a unit other than the control unit. And after executing a control program stored in the RAM by the CPU while maintaining power supply to the control unit after turning off power supply to components other than the control unit. I do.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

[First Embodiment] FIG. 1 is a block diagram showing the configuration of an ink jet printer according to a first embodiment of the present invention.

In FIG. 1, reference numeral 1 denotes an MPU (control unit) such as a microprocessor, which includes a CPU 2, a RAM 3, an input / output port 4, and the like. Note that this input / output port 4
Includes an A / D conversion function.

CPU 2, RAM 3 and input / output port 4
Are interconnected via a bus 5. Reference numeral 6 denotes a power supply circuit of the printer device, which receives AC power supplied from the outside,
This device generates a DC voltage to be supplied to each unit. 7
Is a ROM, which stores a control program for controlling the printer of this embodiment. Reference numeral 8 denotes a host computer, which is connected to a GA (gate array) 9 of the ink jet printer via an interface line 36, and supplies print data to the printer. The GA (gate array) 9 is a host computer 8
And motor drivers 13 and 14
Output of a motor drive signal to the print head 15, and output of print data to the print head 15. 10 is a DRAM,
The recording data received from the host computer 8 via the GA 9 is stored, and the result of the image processing performed by the image processing circuit in the GA 9 is stored. The content of the image processing performed by the GA 9 is instructed under the control of the CPU 2 based on a control program stored in the ROM 7.

Reference numeral 11 denotes a carriage motor, which rotates the recording head 15 mounted on the carriage for main scanning. A paper feed motor 12 is used to convey a recording medium such as recording paper. Reference numerals 13 and 14 denote motor drivers, which correspond to the carriage motors 11 and 14, respectively.
The carriage motor 11 and the paper feed motor 12 are connected to the paper feed motor 12 and driven to rotate by a command from the MPU 1. Each of 37 and 38 is a motor control signal line output from the GA 9 to each motor driver.

The recording head 15 includes a head 16, a head temperature sensor 17 for measuring the temperature of the head 16,
And an ink tank 18. GA9 is C
The print data stored in the DRAM 10 is extracted according to a command from the PU 2, and the print head 1 is output via the signal line 35.
6 for printing. The recording head 16 is an ink-jet type head, and is configured to heat the ink by energizing a heating resistor provided in the nozzle of the head 16 and discharge the ink by the generation of bubbles due to the heat. As described above, since the recording head 16 is of the thermal control type, the temperature of the recording head 15 is monitored by the head temperature sensor 17, and the MPU is used by using the temperature measurement result.
1 is performed. That is, the temperature signal of the recording head 15 detected by the head temperature sensor 17 is input to the input / output port 4 via the signal line 34, where the A / D signal is output.
It is converted and taken into the CPU 2.

Reference numeral 19 denotes an environmental temperature sensor which measures the environmental temperature at which the printer is placed, and the measured temperature signal is input to an input / output port 4 via a signal line 33, where it is A / D converted. Is taken into the CPU 2.

Reference numeral 20 denotes a power switch (power switch)
The switch 20 is pressed by detecting that the switch circuit is closed by being connected to the input / output port 4 by the signal line pair 32. Here, the power switch 20
The CPU 2 is controlled so that the power of the printer device is alternately turned on and off each time is pressed.

The switch 21 controls the supply / interruption of power supplied from the power supply circuit 6 to each section in the printer. That is, the switching of the switch 21 is performed by the switching signal 31 output from the CPU 2 via the input / output port 4. The power supply line 30 output from the switch 21 includes a ROM 7, a GA 9, a DRAM 10, a carriage motor 11, a paper feed motor 12, and a motor driver 1.
3, 14 and the power input terminals of the recording head 15, and can supply / interrupt the power to these elements and each part. As shown in the figure, both the head temperature sensor 17 and the environmental temperature sensor 19 have, for example, a thermistor or the like, and have a voltage supply line and a feedback line.
Since the signal line is connected to the input / output port 4 of the MPU 1, power is always supplied from the power supply circuit 6 via the input / output port 4 regardless of whether the switch 21 is on or off.

In the ink jet printer of this embodiment, it is necessary to calibrate the output of the head temperature sensor 17 periodically or continuously in order to maintain the accuracy of the measurement result of the head temperature in a long term. . This head temperature calibration process is performed based on a comparison between the output of the head temperature sensor 17 and the output of the environmental temperature sensor 19, but the temperature of the head 16 increases during recording or immediately after the recording operation. Not suitable. That is, it is desirable that the calibration of the head temperature be performed when the temperature of the recording head 16 is in a steady state instead of a transient state. Therefore, it is desirable to perform this calibration when the printer is in a standby state, but on the other hand, there is a demand to minimize power consumption during standby. Therefore, in the present embodiment, when the printer is in the standby state, power is supplied to only the minimum elements (elements and the like) necessary for head temperature calibration, and power supply to other elements is cut off. I have to.

That is, in the present embodiment, when the power switch 20 is operated and power off is instructed, the MPU
1. The power supply to elements other than the head temperature sensor 17 and the environmental temperature sensor 19 is cut off to put the apparatus in a standby state.
In this standby state, the head temperature is calibrated, the power switch 20 is monitored, and when the power switch 20 is turned on, the process is shifted to a power-on process.

FIG. 2 is a schematic view showing the structure of the mechanism of the ink jet printer according to the present embodiment. Portions common to those shown in FIG. 1 are indicated by the same reference numerals.

In FIG. 2, the carriage 130 is connected to a part of a belt 133 for transmitting the rotational force of the carriage motor 11, and is slidable with respect to two guide shafts 131A and 131B disposed in parallel with each other. By doing so, a reciprocating motion over the entire width of the recording member of the recording head (inkjet head) 15 becomes possible. By controlling the relative movement between the carriage 130 and the recording member by inputting a predetermined recording signal, a desired recording surface of the recording member sent from the paper supply unit 134 to the position of the platen 135 is controlled. Images are recorded.
The feeding of the recording member is achieved by transmitting the rotation of the paper feed motor 12 to a platen roller or the like.

A head recovery device 136 is provided at one end of the moving path of the recording head 15, for example, at a position facing the home position. The head recovery device 136 is driven by the driving force of the motor 113 via the electric mechanism 132.
And the recording head 15 is capped. In connection with the capping of the recording head 15 by the cap portion 132A of the head recovery device 136, ink suction by a suitable suction means provided in the head recovery device 136 or an appropriate ink provided in the ink supply path to the recording head 15 is provided. An ejection recovery process, such as removing the thickened ink in the liquid path by forcibly discharging the ink in the nozzle by performing pressure feeding by the pressurizing means. Further, the recording head 15 is protected by capping the recording head 15 at the end of recording or the like.

Reference numeral 137 denotes a blade disposed on the side surface of the head recovery device 136 and formed of silicon rubber as a wiping member. The blade 137 is held in a cantilever form by a blade holding member 137A, and like the head recovery device 136, the motor 113 and the electric mechanism 1 are held.
32, the engagement with the ejection surface of the recording head 15 becomes possible. Accordingly, the blade 137 is made to protrude into the moving path of the recording head 15 at an appropriate timing in the recording operation of the recording head 15 or at the time of ejection recovery using the head recovery device 136, and accompanying the moving operation of the recording head 15. Dew, wet or dust on the ejection surface of the recording head 15 is wiped off.

Next, the processing in the ink jet printer of the present embodiment will be described with reference to the flowchart of FIG. The processing of steps S1 and S2 of the program for executing this processing is stored in the ROM 2a of the CPU 2, and the program for executing the other processing steps is stored in the ROM 7.

This processing is performed by the AC power supply connected to the power supply circuit 6.
The plug is started by being connected to a commercial power outlet, and the start of the AC power supply causes a power-on reset to the CPU 2 to jump to a reset vector (step S1). As a result, the program stored in the ROM 2a is executed.
2. Various initial settings such as setting of the input / output port 4 and initialization of the RAM 3 are performed. Then, the process proceeds to a step S3, where it is determined whether or not the power switch 20 is pressed.
When 0 is pressed, the process proceeds to step S4, where a switch switching signal 31 is output and the switch 21 is closed. This gives R
Power supply to the OM 7, the GA 9, the DRAM 10, the motor, the recording head 15, and the like is started. Next, the process proceeds to step S5, and waits for the rise time of each unit due to power supply, proceeds to step S6, and shifts the processing to the control program stored in the ROM 7. Accordingly, the process proceeds to step S7, where the reception of the recording data from the host computer 8, the control of the motor, the recording operation, and the like are executed in accordance with the main program stored in the ROM 7.

If the power switch 21 is depressed in step S8 while the main program is being executed, the flow advances to step S9, and the MPU executes the program stored in the ROM 7 and operated during standby of the printer.
1 and stored in the RAM 3. And step S1
Then, the control right is transferred to the program copied to the RAM 3. Next, the process proceeds to step S11, and the RAM
3 to execute a program to stop power supply to each part of the apparatus, calibrate the head temperature sensor 17, and the like.

Next, step S1 to be executed during this waiting time
The process 1 will be described.

First, in step S111, a switch switching signal 31 is output to open the switch 21, and the power line 3
The power supply to 0 is cut off. Thus, the power supply to the parts other than the MPU 1 is stopped. Next, proceeding to step S112, the temperature value detected by the head temperature sensor 17 and
Based on the temperature value detected by the environmental temperature sensor 19,
The head temperature sensor 17 is calibrated. Next, step S1
In step 13, it is determined whether the power switch 20 has been pressed. If not, the process returns to step S112 to execute the above-described calibration processing. When the switch 20 is pressed, the process proceeds to step S114, and the switch switching signal 3
The switch 21 is closed by 1. As a result, power supply to the power supply line 30 is started. In this way, power starts to be supplied to each part, but there are parts (elements and the like) that do not immediately become operable. Therefore, in step S115, the elapse of the rise time is waited. And step S116
Then, the control right is transferred to the control program stored in the ROM 7. Accordingly, the process proceeds to step S7, in which the main program is operated by the MPU 1 of the printer of the present embodiment, and the power switch 20 is turned on in step S8.
Check whether the host computer 8 has been pressed.
Interface and recording control are executed.

As described above, according to the first embodiment, the calibration process of the sensor for detecting the head temperature can be executed while the power consumption is suppressed in the standby state of the printer.

[Second Embodiment] A second embodiment is an embodiment in which the number of recording heads in the first embodiment is plural. That is, in the printer of the first embodiment, the number of the recording heads 15 is one. However, in the case of a multi-color printer or the like, the recording head may be constituted by a plurality of recording heads.

FIG. 4 is a block diagram showing the configuration of an ink jet printer according to a second embodiment of the present invention. The difference from the configuration shown in FIG. 1 is that the recording head 15 has a yellow recording head 15Y, Recording head 1 for magenta
5M, a recording head 15C for cyan, and a recording head 15K for black.

The head temperature of each recording head is determined by head temperature sensors 17Y, 17M, 17C,
It is detected by inputting a signal from 17K through the input / output port 4. Therefore, as in the first embodiment, the CPU 2 sequentially obtains signals from the head temperature sensors 17Y, 17M, 17C, and 17K of these four recording heads 15Y to 15K via the input / output port 4. Then, a calibration process for each head temperature sensor is performed in comparison with the environmental temperature signal acquired from the environmental temperature sensor 19.

In this case, in step S112 of FIG. 3 described above, the signals from the head temperature sensors of the four recording heads are input, and each sensor signal is compared with the signal from the environmental temperature sensor 19. This can be realized by calibrating the output of each head temperature sensor.

Third Embodiment FIG. 5 is a block diagram showing a configuration of an ink jet printer according to a third embodiment of the present invention. In this embodiment, a clock generator 22 is added to the configuration shown in FIG. ing.

In the third embodiment, when the ink jet printer is in a standby state (idle state), the frequency of the clock signal 40 supplied from the clock generator 22 to the MPU 1 is reduced, so that the MPU 1 in this standby state We try to reduce power consumption. This clock generator 22 can output a clock signal 40 at a frequency division ratio according to a frequency division ratio control signal 39 input via the input / output port 4.
Now, for example, the clock signal 40 of 10 MHz
When it is input to U1, the frequency of the clock signal is set to 5 MHz by setting the frequency division ratio to 1/2 by the frequency division ratio control signal 39.
And supply it to the MPU1. This makes it possible to slow down the operation of the MPU 1 during the standby operation of the printer device, thereby suppressing power consumption.

FIG. 6 is a flowchart showing processing in the ink jet printer of the third embodiment. Steps common to those in the flowchart of FIG. 3 are denoted by the same reference numerals, and their description is omitted.

In FIG. 6, when the power switch 20 is operated to turn off the power in step S8, the process proceeds to step S9, where the control program in the ROM 7 is copied to the RAM 3, and the control is transferred to the program in the RAM 3 in step S10. Then, in step S111, the switch 21
Is opened, and in step S111-1, the frequency division ratio control signal 39
And the frequency division ratio in the clock generator 22 is set to, for example, “” ”, and the frequency of the clock signal input to the MPU 1 is set to 5 MHz.

In step S113, when the power switch 20 is operated to give an instruction to turn on the power, step S1 is executed.
Proceeding to 13-1, the frequency division ratio control signal 39 is output, the frequency division ratio in the clock generator 22 is returned to "1", and the frequency of the clock signal 40 is returned to the original 10 MHz.

As described above, according to the third embodiment, there is an effect that the power consumption can be further reduced in the standby state in the ink jet printer.

[Embodiment 4] FIG. 7 is a block diagram showing the configuration of an ink jet printer according to a fourth embodiment of the present invention. Description is omitted.

In the fourth embodiment, the switch 21 is changed from the normally open switch of the first embodiment to a normally closed switch. Thus, in the first embodiment, the power supply circuit 6 is not connected until the switching signal 31 is output.
The power supply from was only to MPU1
In the fourth embodiment, since the power is supplied to the entire apparatus, the CP
U2 can operate according to the control program stored in the ROM 7 immediately after the power is turned on.
ROM 2a is unnecessary.

The processing in this case is shown in the flowchart of FIG. In FIG. 8, the same step numbers as those in the above-described flowchart are denoted by the same reference numerals, and description thereof will be omitted. As is clear from the comparison between the flowchart of FIG. 8 and the above-described flowchart, in FIG. 8, since the control program stored in the ROM 7 is executed when the power is turned on, the processing of steps S3 to S6 can be omitted. is there.

Even if the present invention is applied to a system including a plurality of devices (for example, a host computer, an interface device, a reader, a printer, etc.), an apparatus (for example, a copying machine, a facsimile, etc.) comprising one device Device).

Another object of the present invention is to provide a storage medium storing a program code of software for realizing the functions of the above-described embodiments to a system or apparatus, and to provide a computer (or CPU) of the system or apparatus.
Or MPU) reads and executes the program code stored in the storage medium.

In this case, the program code itself read from the storage medium realizes the function of the above-described embodiment, and the storage medium storing the program code constitutes the present invention.

As a storage medium for supplying the program code, for example, a floppy disk, hard disk, optical disk, magneto-optical disk, CD-ROM, CD
-R, a magnetic tape, a nonvolatile memory card, a ROM, or the like can be used.

When the computer executes the readout program code, not only the functions of the above-described embodiment are realized, but also an OS (Operating System) running on the computer based on the instruction of the program code. ) Performs part or all of the actual processing, and the processing realizes the functions of the above-described embodiments.

Further, after the program code read from the storage medium is written into a memory provided on a function expansion board inserted into the computer or a function expansion unit connected to the computer, based on the instructions of the program code, The case where the CPU of the function expansion board or the function expansion unit performs part or all of the actual processing, and the function of the above-described embodiment is realized by the processing.

Although the present embodiment has been described with reference to an ink jet printer, the present invention is not limited to this, and may be applied to various printers and computer equipment having a CPU, ROM, RAM and the like. Applicable.

The ROM 7 may be composed of a RAM backed up by a battery, for example.

Further, in the present embodiment, the operation is shifted to the standby state by operating the power switch (power off).
The present invention is not limited to this, and is naturally applicable to a case where the key switch is not operated for a predetermined time or a print command is not received for a predetermined time or the like, and a case where the system automatically shifts to a standby state is performed. .

As described above, according to the present embodiment, the MPU incorporating the CPU, the RAM, and the input / output port
In an electronic device such as a printer having a ROM, a GA, and an external RAM, in a standby state of the device, power supply to other than the MPU is stopped, and a minimum amount of a program loaded in the RAM in the MPU is executed. Power consumption during standby can be minimized. Accordingly, unlike the case where the power supply to the entire electronic device is cut off and the operation is stopped, there is no need to perform a sequence of setting and obtaining the operation parameters of the electronic device at the time of startup, so that the operation can be quickly restarted. This has the effect.

Further, according to the present embodiment, there is an effect that the power consumption in the standby state of the device can be further reduced.

[0055]

As described above, according to the present invention, further power saving can be realized in the standby state.

Further, according to the present invention, the control program to be executed in the standby state is transferred from the memory whose power supply is cut off to the RAM in the control unit. There is an effect that power supply control can be performed.

According to the present invention, in the standby state,
By executing the processing desirably performed in the steady state, power consumption can be suppressed and the standby time can be effectively used.

Further, according to the present invention, the power consumption can be further reduced by reducing the frequency of the clock signal supplied to the control unit in the standby state.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of an inkjet printer according to a first embodiment of the present invention.

FIG. 2 is a schematic view illustrating a configuration of a recording unit of the inkjet printer device according to the embodiment of the present invention.

FIG. 3 is a flowchart illustrating processing in the inkjet printer according to the first embodiment of the present invention.

FIG. 4 is a block diagram illustrating a configuration of an inkjet printer device according to a second embodiment of the present invention.

FIG. 5 is a block diagram illustrating a configuration of an inkjet printer device according to a third embodiment of the present invention.

FIG. 6 is a flowchart illustrating a process in the inkjet printer device according to the third embodiment of the present invention.

FIG. 7 is a block diagram illustrating a configuration of an inkjet printer according to a fourth embodiment of the present invention.

FIG. 8 is a flowchart illustrating a process in the ink jet printer according to the fourth embodiment of the present invention.

Claims (10)

[Claims] 1. An electronic device having a control unit having at least a CPU, a RAM, and an input / output port, and a memory storing a control program executed by the CPU, wherein power is supplied to each unit of the electronic device. A power supply unit, a switch circuit for turning on and off power supply from the power supply unit to other than the control unit, and a transfer unit for transferring a control program stored in the memory to the RAM in response to a power off instruction. Power-off control means for controlling the power supply to other than the control unit to be turned off by the switch circuit after the transfer by the transfer means, and supplying power to the parts other than the control unit by the power-off control means. Is turned off, the CPU supplies the RA while maintaining the power supply to the control unit. Electronic apparatus, characterized in that to execute the stored control program to. 2. The electronic device according to claim 1, wherein the power supply unit supplies power by supplying power from a commercial power supply, and always supplies power to the control unit by supplying power from the commercial power supply. machine. 3. The electronic apparatus according to claim 1, wherein the instruction to turn off the power is given by a switch connected to the input / output port. 4. The electronic device is a printer device, further comprising a temperature sensor connected to the input / output port, wherein the power supply to the control unit is turned off after the power supply to the memory is turned off by the power-off control means. 2. The electronic device according to claim 1, wherein the temperature sensor is calibrated by the CPU while the power supply is maintained. 5. A clock supply unit for supplying a clock signal to the control unit, and after the power supply to the memory is turned off by the power-off control unit, the frequency of the clock signal supplied from the clock supply unit is reduced. The electronic apparatus according to claim 1, further comprising: 6. A power supply control method for an electronic device having at least a control unit having a CPU, a RAM, and an input / output port, and a memory storing a control program executed by the CPU, the power supply control method comprising: A transfer step of transferring a control program stored in the memory to the RAM; and, after the transfer in the transfer step, power supply to a unit other than the control unit from a power supply unit that supplies power to each unit of the electronic device. Turning off the power supply to the control unit other than the control unit, and then maintaining the power supply to the control unit and the CPU
Executing a control program stored in the RAM according to the above method. 7. The power supply according to claim 6, wherein the power supply unit supplies power by supplying power from a commercial power supply, and always supplies power to the control unit by supplying power from the commercial power supply. Supply control method. 8. The power supply control method according to claim 6, wherein the power-off instruction is issued by a switch connected to the input / output port. 9. The power supply control method according to claim 6, wherein in the step of executing the control program, a calibration process of a temperature sensor connected to the input / output port is further performed. 10. The power supply according to claim 6, wherein in the step of executing the control program, the frequency of a clock signal input to the control unit is further reduced. Control method.