CN1983118A - Method for saving power of personal digital aid - Google Patents

Method for saving power of personal digital aid Download PDF

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Publication number
CN1983118A
CN1983118A CN 200510111482 CN200510111482A CN1983118A CN 1983118 A CN1983118 A CN 1983118A CN 200510111482 CN200510111482 CN 200510111482 CN 200510111482 A CN200510111482 A CN 200510111482A CN 1983118 A CN1983118 A CN 1983118A
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China
Prior art keywords
personal digital
digital assistant
standby mode
degree
picture file
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CN 200510111482
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Chinese (zh)
Inventor
李强
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Huanda Computer Shanghai Co Ltd
Mitac International Corp
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Mitac International Corp
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Priority to CN 200510111482 priority Critical patent/CN1983118A/en
Publication of CN1983118A publication Critical patent/CN1983118A/en
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Abstract

An power-saving method of personal digital assistant includes operating system to enter into deep standby module by power-saving monitoring module and compressing operation data in RAM to be memory image file being stored into NVRAM, storing said file into external storage unit if storage space of NVRAM is not enough and interrupting power supply of personal digital assistant completely when storing operation is finished.

Description

The electricity saving method of personal digital assistant
[technical field]
The present invention is a kind of electricity saving method of personal digital assistant, after particularly total system electric power being closed, still can keep operational data in the random access memory and then reach the method for power saving effect.
[background technology]
Personal digital assistant (PDA, Personal Digital Assistant) volume is little, use and be not subjected to the time site limitation, the start execution speed is fast, function can be from simple personal note book to complexity various application software, such as keep accounts, function such as online, satellite navigation, account, quotations on the stock market, multimedia, these all fully show the style and features of digital assistants.Wherein, compact is the attracting valuable feature of personal digital assistant energy, and personal digital assistant weight on the market is about 150 g at present, can directly be put in the pocket, goes to which where is used, and is very convenient.The function that personal digital assistant start back just can be wanted at once also must process detect complicated programs such as internal memory unlike driving computing machine, and efficient improves many relatively.More click and hand-written or add input mode such as keyboard and appoint us to select, these all characteristics make that personal digital assistant obtains to pay attention to day by day, more obtain favorable comment.
But, the electrical problems of personal digital assistant is a mortal wound place always, though present personal digital assistant does not have hard disk, CD-ROM drive, display screen also than notebook computer come little, power consumption situation in comparison is also just well a lot of than notebook computer, but during the notebook computer shutdown is that the power supply of whole machine is all closed, have only when waiting until next electric power starting, just begin to carry out the running of whole machine, but personal digital assistant is pressed power key when start, be not that the power supply of whole machine is closed fully, and only be power-off with screen, and provide part electric power to keep the data in the internal memory in the running, more the meeting of power saving is with central processing unit (CPU, Central Processing Unit) operation frequency reduces, to reduce consumption rate, but however, under complete obsolete situation, still the system that can make of laying out 10 days two weeks loses electric power fully, thus, the data that originally leave random access memory (RAM, Random Access Memory) in will disappear, this can cause very big inconvenience to the very not frequent user of frequency of utilization.
[summary of the invention]
Fundamental purpose of the present invention is to provide a kind of personal digital assistant (PDA, Personal DigitalAssistant) electricity saving method, by the stand-by time that sets according to the user, judge whether random access memory (RAM, Random Access Memory) Nei data, copy to nonvolatile RAM (NVRAM, Non-Volatile Random Access Memory) or in the external memory, so that whole machine enters into dormant state, therefore personal digital assistant no longer produces unnecessary power consumption, and then reaches the effect of power saving.
Therefore, for reaching above-mentioned purpose, the electricity saving method of the disclosed a kind of personal digital assistant of the present invention must comprise at least at hardware aspect:
Setting module is in order to the setting of reception time threshold that the user imported and standby mode startup; System parameter table is in order to threshold value and enter the record of degree of depth standby mode when system writing time; Power saving supervision module in order to the operating state of surveillance, and according to the time value of timer, is judged to start which kind of standby mode; Power management module is supplied with in order to the electric power according to the standby mode Adjustment System; And data-moving module, when entering degree of depth standby mode in system, to compress the mental picture file that forms by operational data, unloading is to nonvolatile RAM or external memory, and when removing degree of depth standby mode, the mental picture file is reduced in the random access memory, makes the state before system recovery becomes to enter common standby mode.
According to purpose of the present invention and reach above-mentioned advantage, the present invention is carrying out before standby mode starts, and comprises the setting and the preposition inspection step of following system:
At first, receive the user and import the time threshold that each standby mode starts, and confirm whether allow various standby modes to be chosen; Whether the remaining space of then checking nonvolatile RAM is greater than the work usage space of random access memory, if the remaining space deficiency, whether the remaining space that then removes to check external memory again is greater than the work usage space of random access memory; If still there are not enough storage spaces, then show the error message that to choose degree of depth standby mode.Otherwise whether the system that continues to monitor has the setting of input shutdown, sets when shutdown and does the time spent, begins to read the time value of timer, whether enters each standby mode to weigh.
When the present invention enters common standby mode by operating mode,, comprise the following step for reducing the power consumption of system:
Confirm whether to arrive the time threshold that enters common standby mode when time value, then, reduce the operation frequency of central processing unit according to timer, then, the power supply that the shutdown system periphery is required only provides internal memory required electric power, continues to read the time value of timer again.
And arrive when entering the time threshold of degree of depth standby mode when the time value of timer, and system allows to enter degree of depth standby mode, for further reaching the effect of power saving, comprised the following step:
At first, operational data in the random access memory is compressed into a mental picture file and is stored to nonvolatile RAM, when if not the remaining space of volatile random access memory is not enough, then dump to external memory, after storage finishes, the information that again system is entered degree of depth standby mode is recorded in the system parameter table, after finishing, promptly closes the power supply of total system.
And when the user reuses personal digital assistant, make the duty of system when standby mode reverts to operating mode, comprise the following step:
At first, look-at-me that the receiving system start is produced and the electric power that recovers central processing unit, then, judge the information record that whether has degree of depth standby mode in the system parameter table, if have then again to seek whether there is the mental picture file to nonvolatile RAM, may be if do not have then for this mental picture file is present among the external memory, read then operational data to be separated push back behind the mental picture file and deposit to random access memory, at last, recovery system overall electric power.So, the preceding duty of standby just can be recovered to enter by system, and can reduce the waste of electric power.
[description of drawings]
Fig. 1 is a system construction drawing of the present invention.
Fig. 2 is an operating mode synoptic diagram of the present invention.
Fig. 3 is the method flow diagram of preposition setting of startup idle function of the present invention and detecting.
Fig. 4 enters the method flow diagram of common standby mode for the present invention.
Fig. 5 enters the method flow diagram of degree of depth standby mode for the present invention.
Fig. 6 reverts to the method flow diagram of operating mode from degree of depth standby mode for the present invention.
[embodiment]
See also Fig. 1, this is a system construction drawing of the present invention, has comprised following parts:
Setting module 190, setting in order to reception time threshold that the user imported and standby mode startup, keyboard, joystick, button, telepilot or the Touch Screens etc. that can comprise called optical imaging are available for users to the device doing to import, in order to receive the setting value that the user chooses and imports, for example: choose which kind of standby mode of setting by setting menu, according to the time threshold of various standby modes input settings.
System parameter table 180 in order to write down the time threshold of various standby modes, reaches the information record that enters degree of depth standby mode 240 when system; Because in a single day system enters degree of depth standby mode 240, job information in the random access memory 120 will disappear because losing electric power supply, therefore must note the time threshold that the user sets, ROM-BIOS 160 can be followed the timer according to inside, calculate whether to arrive and enter degree of depth standby mode 240, and the remaining space of detecting the present nonvolatile RAM 140 of machine-processed gained according to system, and the use situation of external memory 130, to determine when entering degree of depth standby mode 240, extremely where the mental picture file unloading that operational data in the random access memory 120 will be changed, and after unloading is finished, the destination of depositing the mental picture file is recorded in this.In case ROM-BIOS 160 receives the look-at-me of start, can load the mental picture file according to this destination record, and operational data is returned in the random access memory 120.
Power saving supervision module 110 then is the operating state in order to surveillance, and for example whether the user has in operation personal digital assistant 100, perhaps according to the utilization rate of central processing unit, and according to the time value that timer is counted, judges to start which kind of standby mode.
Power management module 170, supply with in order to the electric power of setting Adjustment System according to various standby modes, especially when system is used as the electric power supply source by battery fully, make the service time of battery that long utilization rate can be provided, therefore, must reduce and fall unnecessary power wastage, because personal digital assistant 100 can enter the operating mode 220 of operating system at once in a start, its central processing unit is the situation that is in the continued power running, but if only do not need central processing unit to operate with full rate speed for entering operating mode 220 immediately, so can give frequency reducing to reduce unnecessary power wastage, in addition, the system peripherals device is when the operating mode 220 in when shutdown, also be to provide part electric power required as detecting, yet,, more prolonged the up time of battery if can close this power wastage partly.
Data-moving module 150, in order to when personal digital assistant 100 enters degree of depth standby mode 240, because must be with the operational data in the random access memory 120, by central processing unit it is compressed into a mental picture file, and this mental picture file comprises respectively this operational data and the correspondence position information that is stored in this random access memory 120, but according to the usage space that is write down in the system parameter table 180, the decision unloading is to nonvolatile RAM 140 or external memory 130, and when removing degree of depth standby mode 240, the mental picture file is reduced in the random access memory 120, makes the state before system recovery becomes shutdown.
Therefore, in the present invention, personal digital assistant 100 has comprised 4 kinds of patterns, see also Fig. 2, when system starts shooting for the first time, must carry out initialization action to system, comprise setting-up time and screen calibration, also operating system must be loaded in ROM (read-only memory) (ROM) in the random access memory 120 and carry out, and the running of drive system peripheral unit.After start is finished, promptly enter operating mode 220, in this pattern, the random access memory 120 of system can be possessed electric power to keep the content of work always, when the user presses power key, only can close the power supply of display screen, if surpassing in time of the time threshold that common standby mode 230 sets, the user do not re-used personal digital assistant 100, central processing unit still can be kept low amounts of power, promptly enter common standby mode 230, and when the user presses power key once more, can in display screen, show immediately just to enter operating mode 220 once more by previous picture.
If it is of a specified duration excessively to enter the time of common standby mode 230, then enter into degree of depth standby mode 240, operational datas in the random access memory 120 are dumped to does not need the nonvolatile RAM of electric power (NVRAM, Non-Volatile RAM) 140, for example: EEPROM (Electrically ErasableProgrammable Read-Only Memory), but erasing type ROM (read-only memory) (EPROM, ErasableProgrammable Read-Only Memory), or flash memory (flash memory) is as Sheffer stroke gate flash memory (NAND Type Flash Memory), rejection gate flash memory (NorFlash, NOR Type Flash Memory); Or external memory 130, as micro hard disk (micro-driver) etc.
Therefore when entering standby mode, the user must do individual settings at common standby mode 230 and degree of depth standby mode 240, please refer to Fig. 3, at first, when the user chooses common standby mode 230 and degree of depth standby mode 240, can set respectively this time threshold and be recorded in system parameter table 180 (step 310), power saving supervision module 110 just can determine whether entering standby mode according to these time thresholds that configures, when system enters degree of depth standby mode 240, because the operational datas in the random access memory 120 want unloading to need not on the nonvolatile RAM 140 or external memory 130 that electric power keeps, and the access speed of nonvolatile RAM 140 is very fast, and consumption rate is low, but therefore detect remaining usage space size in the nonvolatile RAM 140 earlier, judge whether greater than the shared amount of capacity (step 320) of operational data in the random access memory 120, if not the insufficient space that volatile random access memory 140 is last, whether the storage space of then detecting external memory 130 again has enough remaining spaces to store operational data in the random access memory 120 well, wherein the maximum use amount of operational data is not more than the capacity (step 330) of whole random access memory 120, if do not have, then show the error message (step 360) that can't choose degree of depth standby mode 240, the option of for example choosing degree of depth standby mode 240 is (disable) state that lost efficacy.Same, if the user is in follow-up use, if when making the remaining space of external memory 130 less than work data big or small, must show that also an error message is with the prompting user, when the user selects to close when entering degree of depth standby mode 240 functions, can use in the external memory 130 to be 240 of the degree of depth standby modes reserve area spaces of reservation in advance.
After the reserve area destination is selected, this information is recorded in the system parameter table 180, then, whether power saving supervision module 110 just can begin monitoring system has the situation that causes entering degree of depth standby mode 240 that (step 340) takes place, and receive the user imports setting value in setting module 190 modification at any time, according to amended setting value and read the time value (step 350) of timer, judge whether system reaches the time threshold that starts standby mode.
Therefore, after the preposition setting of personal digital assistant 100 is finished, can start standby mode at any time to reduce power consumption.Please refer to Fig. 4, when power saving supervision module 110 finds that the user had not operated personal digital assistant 100 for some time, after perhaps the user has pressed the power key powered-down, because system still can provide central processing unit and peripheral unit electric power when waiting for that at any time the user presses power key once more, can get back to operating mode 220 rapidly, and can allow the user continue immediately to handle previous work, but if surpass when setting the time threshold that common standby mode 230 starts, then can start common standby mode 230 (step 410), the operation frequency of central processing unit is reduced (step 420), though one comes the user to press power key again to have a sensation that running postpones at the beginning rising when using personal digital assistant 100 even so, but when returning, the frequency adjustment can recover normal, and the time that postpones can't be too of a specified duration, same, the also power supply of shutdown system periphery, only provide random access memory 120 to keep the required electric power (step 430) of operational data, the so consumption that more can save electric power, can't be when inserting storage card but the cost of paying is the user, open system power supply immediately, or when oneself outside of user connects system through external-connected port, open system is to set immediately, whether but can save long-time standby detecting has peripheral unit to produce the spent electric power of interruption, at last, continue to read the time value (step 440) of timer, further then to judge whether to reach the time threshold of degree of depth standby mode 240.
Please refer to Fig. 5, work as the unused time, after just the user presses power key, when having surpassed the time threshold that degree of depth standby mode 240 sets, then start the consumption of degree of depth standby mode 240 with further saving electric power, owing to enter only surplus random access memory 120 of the common standby mode 230 remaining power consumption in back and central processing unit, with in response to the user once more during PDA 100, can get back to operating mode 220 immediately, but if the unused time has surpassed the time threshold that degree of depth standby mode 240 sets, it is of a specified duration excessively perhaps to enter common 230 times of standby mode, then start degree of depth standby mode 240 (step 510), then, central processing unit just is compressed into a mental picture file with operational data in the random access memory 120, and by data-moving module 150 with mental picture file storage (step 520) to the nonvolatile RAM 140, if the remaining space deficiency of record nonvolatile RAM 140 in the system parameter table 180, then be stored to external memory 130 (step 530), the information that the system that is about to after storage finishes enters degree of depth standby mode 240 also is recorded in the system parameter table 180 (step 540), at last, power management module 170 is with the power-off (step 550) of total system.
And when the user presses power key once more, because personal digital assistant 100 has entered degree of depth standby mode 240, power on mode 210 must be entered again and operating mode 220 when originally not shutting down could be reverted to again, please refer to Fig. 6, this is the method flow diagram of the present invention when degree of depth standby mode 240 is started shooting, at first, receive the user and press the look-at-me that power key produces system boot, and the electric power (step 610) of recovery central processing unit, to carry out the required computing of follow-up start, then just judge whether in system parameter table 180, to have the record (step 620) of degree of depth standby mode 240, use the neither record that has to exist because start shooting for the first time when intrasystem residual memory space deficiency or system, if there is the record that system enters degree of depth standby mode 240, then the position of being stored by the mental picture file by data-moving module 150 with its loading, and operational data separated to push back deposit to the random access memory 120 (step 630), at last with the power recovery (step 640) of system, then personal digital assistant 100 can revert to the state that enters before the common standby mode 230.
Store the mental picture file though will take the storage space of a part through the present invention, and when system recovery, need the long time to carry out system reducing, but if in the long run, when the user does not re-use personal digital assistant 100 for a long time, then can keep most of electric power in the battery, use immediately in the time of can starting shooting for the user next time.

Claims (11)

1, a kind of electricity saving method of personal digital assistant, be used to have a random access memory, the personal digital assistant of a nonvolatile RAM and an external memory, and the time that this personal digital assistant enters a common standby mode surpasses the time during threshold value, make this personal digital assistant enter a degree of depth standby mode, this method comprises the following step:
With the complex operational data in this random access memory, be compressed into a mental picture file;
Store this mental picture file to this nonvolatile RAM;
When the remaining space of this nonvolatile RAM is not enough, store this mental picture file to this external memory;
Write down this personal digital assistant and enter the information of this degree of depth standby mode in a system parameter table; And
Closing a battery electric power of this personal digital assistant supplies with.
2, the electricity saving method of personal digital assistant as claimed in claim 1 is characterized in that: this electricity saving method also comprises this personal digital assistant required the following step when this degree of depth standby mode reverts to a normal operating mode:
Recovering a battery electric power of this personal digital assistant supplies with;
Read this mental picture file and will be respectively this operational data separate the correspondence position that pushes back this random access memory; And
Show the system's picture that enters this common standby mode.
3, the electricity saving method of personal digital assistant as claimed in claim 1 is characterized in that: this mental picture file comprises respectively this operational data and the correspondence position information that is stored in this random access memory.
4, the electricity saving method of personal digital assistant as claimed in claim 1 is characterized in that: this external memory can have a reserve area space in order to store this mental picture file.
5, the electricity saving method of personal digital assistant as claimed in claim 4 is characterized in that: this reserve area space can be released when removing this degree of depth standby mode of this personal digital assistant.
6, the electricity saving method of personal digital assistant as claimed in claim 1 is characterized in that: when this remaining space was not enough, then degree of depth standby mode function was shown as the state that can't be chosen.
7, a kind of personal digital assistant of saving power consumption except that having a random access memory, a nonvolatile RAM and an external memory, still comprises following modules:
One setting module is in order to receive the complex time threshold that a user is imported at a common standby mode and a degree of depth standby mode;
One system parameter table, respectively this time threshold and this personal digital assistant enter a record of this degree of depth standby mode in order to record;
One power saving supervision module in order to monitoring the operating state of this personal digital assistant, and when the time value that a timer is counted arrives respectively this time threshold of setting, starts respectively this standby mode;
One power management module when being used to this personal digital assistant and starting respectively this standby mode, is adjusted the electric power of this personal digital assistant and is supplied with; And
One data-moving module, when entering this degree of depth standby mode in this personal digital assistant, with a mental picture file unloading to this nonvolatile RAM or this external memory, and when removing this degree of depth standby mode, this mental picture file is reduced in this random access memory.
8, personal digital assistant of saving power consumption as claimed in claim 7 is characterized in that: this mental picture file is compressed by the complex operational data in this random access memory to form.
9, personal digital assistant of saving power consumption as claimed in claim 7 is characterized in that: this mental picture file also comprises the correspondence position information that this operational data respectively is stored in this random access memory.
10, personal digital assistant of saving power consumption as claimed in claim 7 is characterized in that: this external memory can have a reserve area space in order to store this mental picture file.
11, personal digital assistant of saving power consumption as claimed in claim 10 is characterized in that: this reserve area space can be released when removing this degree of depth standby mode of this personal digital assistant.
CN 200510111482 2005-12-14 2005-12-14 Method for saving power of personal digital aid Pending CN1983118A (en)

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CN 200510111482 CN1983118A (en) 2005-12-14 2005-12-14 Method for saving power of personal digital aid

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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102346538A (en) * 2010-08-04 2012-02-08 华硕电脑股份有限公司 Computer system
CN102376322A (en) * 2010-08-20 2012-03-14 环达电脑(上海)有限公司 Portable electronic equipment control device and method
US8683245B2 (en) 2010-08-04 2014-03-25 Asustek Computer Inc. Computer system with power saving function
CN111984201A (en) * 2020-09-01 2020-11-24 云南财经大学 Astronomical observation data high-reliability acquisition method and system based on persistent memory
CN112363766A (en) * 2020-11-10 2021-02-12 北京百瑞互联技术有限公司 Integrated circuit ultra-low power memory content retention system, method and medium

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102346538A (en) * 2010-08-04 2012-02-08 华硕电脑股份有限公司 Computer system
US8683245B2 (en) 2010-08-04 2014-03-25 Asustek Computer Inc. Computer system with power saving function
CN102346538B (en) * 2010-08-04 2014-11-26 华硕电脑股份有限公司 Computer system
CN102376322A (en) * 2010-08-20 2012-03-14 环达电脑(上海)有限公司 Portable electronic equipment control device and method
CN111984201A (en) * 2020-09-01 2020-11-24 云南财经大学 Astronomical observation data high-reliability acquisition method and system based on persistent memory
CN111984201B (en) * 2020-09-01 2023-01-31 云南财经大学 Astronomical observation data high-reliability acquisition method and system based on persistent memory
CN112363766A (en) * 2020-11-10 2021-02-12 北京百瑞互联技术有限公司 Integrated circuit ultra-low power memory content retention system, method and medium
CN112363766B (en) * 2020-11-10 2024-06-21 北京百瑞互联技术股份有限公司 Content holding system, method and medium for ultra-low power consumption memory of integrated circuit

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