JP2002055731A - Power control method and recording and reproducing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce power consumption by stopping the supply of any clock to a CPU when a task processing is in a waiting state in a device for controlling recording and reproduction by a controller equipped with a microcomputer having a CPU. SOLUTION: This power consumption control processing method of a device to be operated with a battery as a power source for switching and processing plural tasks comprises a step for switching tasks based on the priority order of those tasks and/or the processed situations of those tasks, a step for stopping an operating clock to be supplied to a CPU when the priority order of the switched task is the lowest, and a step for supplying the operating clock to the CPU for continuing the operation when a request for the processing of the task whose priority order is higher than that of the task leading to the stop of the operating clock.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power control method and a recording / reproducing apparatus, and more particularly, to a portable device which operates with a plurality of tasks, prepares a task having a lower priority than a normal task, and performs other tasks. Provided is a power control method and a recording / reproducing apparatus which reduce power consumption by transferring control to a task having the lowest priority when the task is not operating and shifting to a power saving mode.

[0002]

2. Description of the Related Art In a portable device using a battery according to the prior art, in order to reduce current consumption, a microcomputer checks the operating state of peripheral circuits and controls so that the power is turned off when the microcomputer is not operating. Is well known.

[0003] For example, Japanese Patent Application Laid-Open No. 6-9652 of the same applicant.
In the power reduction method disclosed in Japanese Patent Publication No. 0, the read bit rate of the reproduced data per unit time is set to be lower than the storage bit rate of the reproduced data within the unit time as a buffer for the reproduced data from the data detecting means. The reproduction data read out from the storage means is output as a reproduction sound signal in the reproduction signal processing means, and especially for all or some circuit parts in the data reading means. Switch means capable of interrupting the clock is provided, the control means opens and closes the switch means in accordance with the amount of data stored in the storage means, and stops the operation of the data read means during the non-operation period of the data read means. Configure so that power is not consumed.

[0004]

However, in the method for reducing the current consumption described in the prior art, the current consumption of the microcomputer itself has become a considerable ratio as the measures for reducing the power consumption have been advanced. Reduces power consumption when the microcomputer is in an idle state, such as in a loop operation in which the microcomputer itself waits for a response to a peripheral circuit or does not control an input block, or simply waits for a processing request to occur. There is a problem that can not be.

[0005] Therefore, there is a problem which must be solved by controlling the power supply of the microcomputer itself according to the operation state to reduce the power consumption.

[0006]

In order to solve the above problems, a power control method and a recording / reproducing apparatus according to the present invention have the following methods and configurations.

(1) In a power consumption control method for a device which operates using a battery as a power source and switches and processes a plurality of tasks, a step of switching tasks based on the priority of the tasks and / or the processing status of the tasks. ,
If the switched task has the lowest priority, there is a step of stopping the operation clock supplied to the CPU and a task processing request having a higher priority than the task of stopping the operation clock. Supplying an operation clock to the CPU to continue the operation when the power supply is performed. (2) In addition to the step of stopping the operation clock supplied to the CPU, the method further comprises a step of stopping the peripheral clock supplied to peripheral circuits. (1)
3. The power control method according to 1. (3) The power control method according to (1), wherein the device is a recording / reproducing device capable of recording and / or reproducing digital content. (4) The power control method according to (1), wherein the CPU is mounted on a microcomputer.

(5) In a recording / reproducing apparatus which operates by using a battery as a power supply, a task processing means for processing a plurality of tasks for controlling the operation of the recording / reproducing apparatus; A task supplying means for instructing a task to be processed, a clock supplying means for supplying an operation clock to the task processing means, and a task processed by the task processing means being a sleep task having the lowest processing priority. Clock stop requesting means for instructing the clock supply means to stop supplying the operation clock to the task processing means, and a new task for controlling the operation of the recording / reproducing apparatus has occurred while the task processing means is in sleep. In this case, a clock for instructing the clock supply means to resume supply of the operation clock to the task processing means is provided. Recording and reproducing apparatus and a supply request means.

As described above, the clock of the CPU can be stopped when the microcomputer is in the processing waiting state.
Since the clock of the CPU can be stopped frequently even while the system is operating, power consumption can be reduced by that amount, so that the power storage state of the battery can be extended especially in a device driven by a battery. .

[0010]

Next, an embodiment of a power control method and a recording / reproducing apparatus according to the present invention will be described with reference to the drawings.

An electronic apparatus having a power control function for realizing a power control method, and in an embodiment, an MD (Mini)
As shown in FIG. 1, the recording / reproducing apparatus of Disc) includes a power supply unit 110 composed of a battery, a data writing / reading unit 120 composed of a recording medium, and a disk-shaped recording / writing unit of the data writing / reading unit 120. A servo unit 130 for controlling the rotation of the medium 121 and an RF decoder unit 140 for reading and decoding signals recorded on the disk-shaped recording medium 121
, An audio compression decoder section 150, an amplification section 160, an audio output section 170, and a system controller 180.

The data writing / reading section 120 has a disk-shaped recording medium 121 and a head section 122 for writing or reproducing digital content data on or from the disk-shaped recording medium 121.

The audio compression decoder 150 is an ATR for compressing an audio signal and expanding recorded data to an original state.
AC (Adaptive Transform Aco)
and a shock proof memory 152 which is a data buffer for compensating for a difference between a data input amount and an output amount between the rotational speed of the disk-shaped recording medium 121 and the audio compression ratio.

A system controller 180 includes a clock controller 183 for controlling a peripheral clock 181 and a CPU clock (operation clock) 182 supplied to the peripheral circuit and the microcomputer 190, and a CPU (Central Pro).
processing unit) 184, an INT (Interrupt) controller 185 for controlling an interrupt, a timer 186, a ROM 187, a RAM 188,
It comprises a microcomputer 190 having a DMA 189 and a switch 191 for controlling the supply of power to peripheral circuits. The microcomputer 190 and the clock control unit 183 are configured to control the supply of power to the peripheral circuits and the servo unit 130. When a task that is not directly related is operating, the power is turned off and stopped. I do. For example,
When the rotation control by the servo unit 130 is not required, the switch 190a is turned off to stop the power supply to the servo unit 130. Also, while a task in the peripheral area, for example, which is not directly related to key input, is processing, the switch 191b for supplying power required for key input is turned off to put the key input in a standby state. As described above, the system controller 180 including the microcomputer 190 that performs power control is provided with various tasks according to the operation control mode. Each task is assigned a priority, and a job processed by each task is performed. Are different.

FIG. 2 shows a processing form of a task with a priority.
The task to be processed is assigned. For example, when the event is “sound output”, task 1 is processed (ST
11) If it is determined that the reproduction data stored in the memory 152 has reached a predetermined amount or less, the task 1
In (ST11), processing of task 3 for driving an “I / O disk” for data input is performed (ST12), and reproduction data of a predetermined amount or more is stored in the memory 152 from the disk-shaped recording medium 121. When the processing of task 3 is completed by being read, the processing of task 1 is performed again (ST13). When the processing of the task 1 is completed, the fourth task 4 that has been waiting for the processing during the processing of the tasks 1 and 3 is processed (ST1).
4) If there is a processing request for task 1 having a higher priority in the middle, task 4 interrupts the processing in the middle and gives priority to the processing of task 1 (ST15). When the processing of the task 1 is completed, it is confirmed that there is no task with a higher priority, and the processing of the task 4 interrupted in the middle is performed (ST4).
16). When all tasks are processed, the task in the “Sleep” state having the lowest priority is started (ST1).
7). Since the task in the “Sleep” state has no processing of all tasks, the clock control unit 183 supplies the operation clock (CPU clock) 182 supplied to the CPU 184 based on an instruction from the CPU 184. Stop.

When the processing of task 2 occurs in a stopped state, the clock control unit 183 sends the CPU clock 182 in accordance with an instruction from the INT controller 185.
Start for 4. When the supply of the CPU clock 182 starts, the CPU 184 resumes the operation and processes the task 2 (ST18). When the processing is completed, the next task 3 is processed (ST19). When the processing is completed, the processing is performed again. Since there is no task to be performed, the state is set to “Sleep”, and the supply of the CPU clock 182 is controlled by the clock control unit 1.
83 stops again (ST20).

As described above, when all the processes by the tasks in the processing mode are eliminated, the task is shifted to the "Sleep" state. When the task is in the “Sleep” state, the CPU 1
By stopping the clock to 84 and stopping the activity of the CPU 184 itself, when the so-called microcomputer 190 enters an idling state, the clock of the CPU 184 itself can be stopped to stop its activity. It is possible to wait for a processing request without consuming power in a so-called idling state in which a plurality of steps are looped to detect an interrupt or the like by idling.

Next, with reference to FIGS. 3 and 4, the task management in the MD in the MD recording / reproducing apparatus shown in FIG. 1 will be described.

As shown in FIG. 3, the task converts the mode according to the display management task 230 for managing the display on the main body display unit 210 and the remote control display unit 220, the key interrupt 240, the timer interrupt 250, and the like. Mode transition task 260, an audio management task 290 for managing output to the audio unit 270 and interruption 280 to the audio unit 270, TOC (Table O).
f Contents) management task 300, a mechanical unit 310 for controlling the rotation of the disk-shaped recording medium, a servo management task 330 for managing a servo interrupt 320, and a sleep task 340.

The mode transition task 260 is a task for managing the entire system, and is activated by the key interrupt 240 or the timer interrupt 250 and gives an instruction to another task based on the given instruction. For example, when an instruction of “PLAY” is received from the key interrupt 240, the TOC management task 3
00, and instructs the display management task 230 that the state has changed to reproduction. TOC management task 30
0 designates a read address to the servo management task 330 when receiving the playback display, and gives a read instruction of the disk which is the disk-shaped recording medium. 290 is given a sound output instruction. The display management task 230 creates display data in order to switch to the display at the time of reproduction, and causes the main body display unit 210 and the remote control display unit 220 to display the display data. Instructions between tasks are performed through events. The servo management task 330 instructs the mechanical unit 310 to read data from the disk, and is notified of the end by the servo interrupt 320. The audio management task 290 instructs the audio unit 270 to output sound, and the audio interrupt 280 notifies the end of the sound. In this way, various processes are performed by the tasks. Compared with the configuration shown in FIG. 1, the audio management task 290 controls the amplifying unit 160 and the audio output unit 170 corresponding to the audio unit 270, and performs the servo management. Task 330 is the mechanical unit 31
It controls the data writing / reading unit 120 and the servo unit 130 corresponding to 0.

In the present invention, in addition to the control management by the above-mentioned task which has been conventionally employed, the sleep task is controlled when all of the tasks are in an event reception waiting state and all the interrupt processes are not operating. To stop the clock of the CPU of the microcomputer and shift to the power saving mode.

As described above, in order to stop the clock and shift to the power saving mode, the sleep task and the tasks other than the sleep task (normal tasks) are prioritized to lower the priority of the sleep task. There is a need.

For example, as shown in FIG.
Audio management task 290, servo management task 3 during
30, when the display management task 230 is in an operable state, it is connected to the ready queue, control is turned around in order to perform processing, and passes control to the next task. The task for which the processing has been completed is put into a waiting state, and is connected to the ready queue again when it becomes operable by receiving an event from another task or an interrupt.

Then, as shown in FIG. 5, when all of these normal tasks are in a waiting state, a sleep task having a lower priority is activated. In this state, the microcomputer 190
Since no processing is performed (see FIG. 1), the microcomputer 190 is set in a state where it can be started when an interrupt occurs, and
To sleep. That is, when the sleep task 340 having the lowest priority is activated, the clock control unit 183 sets C
The CPU clock 182 to the PU 184 is stopped to put the microcomputer 190 into a sleep state. In this state, if any interrupt occurs, the clock controller 183
CPU clock 184 is supplied from the microcomputer 19
When 0 rises and the normal task is interrupted by the interrupt processing, the sleep task is switched to the normal task and the processing is executed. By performing the above control,
Only when the microcomputer 190 is executing the process, the CPU 184 of the microcomputer 190 is operating.

[0025]

As described above, the power control method and the recording / reproducing apparatus according to the present invention can stop the clock of the CPU when the microcomputer is in the processing standby state, so that the power control method and the recording / reproducing apparatus are frequently used even when the apparatus itself is operating. The power saving mode can be performed, and the power consumption can be reduced accordingly.

[Brief description of the drawings]

FIG. 1 is an overall block diagram schematically showing a configuration of a recording / reproducing apparatus according to the present invention.

FIG. 2 is an explanatory diagram showing the task processing.

FIG. 3 is an explanatory diagram showing tasks that operate on the MD recording / reproducing device.

FIG. 4 is an explanatory diagram showing a ready queue of a task in the recording / reproducing apparatus in FIG. 3;

FIG. 5 is an explanatory diagram showing a ready queue of a task in the recording / reproducing apparatus in FIG. 3;

[Description of Signs] 110; power supply unit, 120; data write / read unit, 13
0: Servo unit, 140; RF decoder unit, 150; Audio compression decoder unit, 151; ATRAC decoder unit, 15
2; memory, 160; amplifying section, 170; audio output section, 1
80; system controller; 181; peripheral clock;
182; CPU clock, 183; clock control unit, 1
84; CPU, 185; INT controller, 186;
Timer, 187; ROM, 188; RAM, 189; D
MA, 190; microcomputer, 191; switch, 190
a; switch, 190b; switch, 210; main body display section, 220; remote control display section, 230; display management task, 240; key interrupt, 250;
60; mode transition task, 270; audio section, 28
0; audio interrupt, 290; audio management task, 300; TOC management task, 310;
0: servo interrupt, 330: servo management task

Claims (5)

[Claims] 1. A power consumption control method for an apparatus that operates using a battery as a power source and switches and processes a plurality of tasks, comprising: a step of switching tasks based on a priority of the tasks and / or a processing state of the tasks; If the switched task has the lowest priority, there is a step of stopping the operation clock supplied to the CPU, and a task processing request having a higher priority than the task of stopping the operation clock. Supplying an operation clock to the CPU to continue the operation when the power supply is performed. 2. The power control method according to claim 1, further comprising a step of stopping a peripheral clock supplied to a peripheral circuit, in addition to the step of stopping the operation clock supplied to the CPU. 3. The power control method according to claim 1, wherein the device is a recording / reproducing device capable of recording and / or reproducing digital content. 4. The power control method according to claim 1, wherein said CPU is mounted on a microcomputer. 5. A recording / reproducing apparatus which operates by using a battery as a power supply, a task processing means for processing a plurality of tasks for controlling the operation of the recording / reproducing apparatus, and a task processing means based on task priorities. A task supply unit for instructing a task to be processed; a clock supply unit for supplying an operation clock to the task processing unit; and a task to be processed by the task processing unit is a sleep task having the lowest processing priority. Clock stop requesting means for instructing the clock supply means to stop supplying the operation clock to the task processing means; and when a new task for controlling the operation of the recording / reproducing apparatus occurs while the task processing means is in sleep. A clock that instructs the clock supply means to resume supply of the operation clock to the task processing means Recording and reproducing apparatus and a sheet requesting means.