JP2003271450A - Program storage system and camera - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To control various functions under optimum conditions by switching memory storage areas for storing control programs in accordance with operation current consumption, rewrite durable times, and operation speed. <P>SOLUTION: In a program storage system which has a plurality of memories with different operation current consumption and stores the control programs in the plurality memories by function, among the control programs, the programs for executing functions which need to operate at all times are stored in the memories which can save the current consumption (#101→#102). <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention has a plurality of memories having different characteristics, and selects a storage destination as to whether to store each program for executing various functions in a memory which is out of order among the plurality of memories. The present invention relates to a storage system and a camera equipped with the storage system.

[0002]

2. Description of the Related Art Conventionally, as a system for controlling a camera, a one-chip microcomputer in which a microcomputer (hereinafter referred to as a microcomputer), a memory, peripheral devices and the like are incorporated in the same chip, a system using a plurality of microcomputers for each function, etc. Is often used.

Also in the control program, the program scale tends to expand due to the multi-functionality and the high functionality, and it is required to increase the program capacity and the memory capacity.

Further, as the scale of the program expands, defects such as program mistakes also tend to increase. Therefore, a program that was conventionally made in a mask ROM is partially made in a non-volatile memory or the like. ROM, EE
Camera control systems having a plurality of memories, such as a microcomputer having a built-in flash memory together with a PROM, are also widely used.

As a camera system which actually uses a plurality of memories including a flash memory, Japanese Patent Laid-Open No. 2000-
According to this publication, a flash memory and an EEPROM are used, and large-capacity data that does not need or is not rewritten in the flash memory and small data that is rewritten in the EEPROM are stored in the flash memory and the EEPROM, respectively. It has been proposed to store a plurality of memories so that they can be used efficiently and without shortening the life.

Further, in Japanese Unexamined Patent Publication No. 8-227359, the flash memory is divided into a plurality of blocks, and by providing a means for rewriting only that specific block, the contents of the entire area of the flash memory are rewritten at the time of rewriting. It has been proposed to make the system easy to change the program without rewriting all.

[0007]

However, in the above-mentioned conventional examples, all of them are made according to the writing characteristics of the non-volatile memory, and although the type of memory is devised according to the scale of the data or program to be written, No other proposal has been made for the characteristics of the memory (operating voltage (= operating current consumption), operating frequency, etc.).

In particular, for a camera such as a battery whose power source is a battery, it is desired to efficiently control the camera operation while suppressing the power consumption as much as possible, but no proposal has been made regarding this.

(Object of the Invention) The object of the present invention is to optimize various functions by appropriately switching the storage destination of the memory for storing the control program in accordance with the relationship between the operating current consumption, the number of rewriting endurance and the operating speed. An object of the present invention is to provide a program storage system and a camera that can be controlled according to conditions.

[0010]

In order to achieve the above object, the invention according to claim 1 has a plurality of memories having different operating current consumption, and a control program is stored in the plurality of memories for each function. In the program storage system to be stored in any one of the control programs, the program for executing a function that needs to be constantly operated is a program storage system to be stored in a memory capable of suppressing current consumption.

In order to achieve the above, the invention as set forth in claim 3 has a plurality of memories having different rewriting endurance times, and stores a control program for each function in any of the plurality of memories. In the storage system, a program that executes a function that requires rewriting data in the memory each time a predetermined operation is performed is a program storage system that stores the program in a memory that has a large number of rewrite endurance times.

In order to achieve the above, the invention according to claim 5 has a plurality of memories having different operation speeds, and stores a program for control in any one of the plurality of memories for each function. In the system, a program that executes a function that requires accuracy is a program storage system that is stored in a memory that can operate at high speed.

In order to achieve the above, the invention according to claim 7 has a plurality of memories each having different operating current consumption, rewriting endurance, and operating speed, and the control program is provided for each function. In the program storage system to be stored in any of the above memory, the program for executing the function that requires the constant operation in the control program is stored in the memory that can reduce the current consumption, and the constant operation is required. For a program that executes a function that requires rewriting the data in the memory each time a predetermined operation is performed, instead of storing such a function, store it in a memory that has a large number of rewrite endurances, and Instead of a function that needs to rewrite the data in the memory each time it is executed, a program that executes a function that requires accuracy Information, is to a program storage system for storing operable in memory at high speed.

In order to achieve the above, the invention described in claim 8 is a camera equipped with the program storage system according to any one of claims 1 to 7.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will now be described in detail based on the illustrated embodiments.

FIG. 1 is a block diagram showing a schematic configuration of a camera system according to each embodiment of the present invention.

Reference numeral 1 denotes a one-chip microcomputer which is a control means for controlling various operations of the camera, and is constituted by a CPU (central processing unit), a mask ROM, an EEPROM, a flash memory, a RAM, a peripheral circuit (not shown) and the like. Then, all the data area, program area, I / O, etc. are stored in the same memory space. Reference numeral 2 is an AF circuit for obtaining distance data to a subject or defocus data of a photographing lens using a sensor for distance measurement or focus detection, and performing focusing operation of the photographing lens based on the information based on the data, 3 is photometry An AE circuit 4 that obtains subject brightness data by using a sensor and controls exposure based on information based on the subject brightness data is a shutter control circuit that controls opening and closing of the shutter. Reference numeral 5 denotes a switch (SW) circuit including switches SW1 and SW2 for starting a photographing operation and switches for setting each photographing mode and the like.

Reference numeral 6 denotes a DC / DC circuit, which converts the power supply voltage into a predetermined voltage and supplies it to each circuit. Reference numeral 7 is a known strobe circuit, which charges the main capacitor and emits strobe light. Reference numeral 8 denotes an oscillator circuit for supplying a clock to the microcomputer 1, which generates two types of operation clocks, high speed and low speed. Reference numeral 9 denotes a display circuit made of a liquid crystal or the like, which displays a battery remaining amount, displays various kinds of photographing information, and gives a warning. Reference numeral 10 is a motor control circuit for controlling a feeding motor and a lens barrel driving motor for winding and rewinding the film.

Before describing each of the embodiments, the general characteristics of each memory provided as a memory in the camera system will be described. The operating frequency is the vertical axis and the operating voltage is the horizontal axis. , Will be briefly described with reference to FIGS. 6 to 8 respectively.

FIG. 6 shows the characteristics of the mask ROM, which is characterized in that the operating voltage is guaranteed up to 1.5 V although the operating frequency is slow.

FIG. 7 shows the characteristics of the flash memory. The operating voltage is as high as 2.8 V, but the operating frequency is high.

FIG. 8 shows the characteristics of the EEPROM. Although the operating voltage and the operating frequency are similar to those of the flash memory, they are different from the flash memory in that only a small memory area can be accessed with a small amount of data. .

Below, a program for executing various functions of the camera is executed by the microcomputer 1 of the camera system having the above-mentioned configuration.
Which of the memories shown in, for example, FIGS. 6 to 8 is appropriate to store (in a battery such as a camera that uses a battery as a power source, for example, camera operation can be efficiently performed while suppressing power consumption as much as possible). The operation of determining whether the control can be performed) will be described.

The setting of the memory for storing the program is performed by the microcomputer 1 of FIG. 1 based on the flowcharts shown in the following embodiments.

(First Embodiment) With respect to the operation of determining in which memory it is appropriate to store a program for executing a clock function among various functions of the camera system having the above-described configuration, the first embodiment of the present invention will be described. The first mode will be described with reference to the flowchart of FIG.

As is well known, the clock function keeps operating to count time. In such a case, in order to continue operation with a limited power supply for a long period of time, it is desirable to operate in a state where current consumption is as small as possible.

Therefore, when the storage destination memory is selected according to the flowchart of FIG. 2, step # 1
At 01, it is determined whether or not the clock function is a function that always operates. Since the clock function is a function that always operates, the process proceeds from step # 101 to step # 102, and the program is written in the mask ROM having the characteristics shown in FIG.

On the other hand, when the function is a function other than the always operating function such as the clock function, the process proceeds to step # 103, and a memory suitable for the function, for example, a flash memory having the characteristics shown in FIG. EEP with the indicated characteristics
The function will be written in the ROM.

As described above, the clock function requires constant operation, and it is desired that the power consumption be as small as possible. Therefore, among the memories, the program is stored in the memory (mask ROM), which has the least operation power consumption. By doing so, a clock function with less battery consumption can be realized.

In addition to this, as a function that is desired to have low power consumption, there is a switch operation monitoring function.

(Second Embodiment) An operation for determining in which memory a program for executing an autofocus function (hereinafter, referred to as an AF function) among various functions of the camera system having the above-mentioned configuration is appropriate to be stored. This will be described as a second embodiment of the present invention with reference to the flowchart of FIG.

The AF function is performed before the photographing operation, and particularly when it takes time to calculate the distance measurement data or the focus detection data, it directly leads to the photographing time lag (hereinafter referred to as the release time lag), and the scene to be photographed is taken. You will miss it. In such a case, it is desirable that the operating frequency is also high in order to increase the calculation speed.

Therefore, when the storage destination memory is selected according to the flowchart of FIG. 3, step # 2
At 01, it is determined whether the calculation speed is required. A
In the case of the F function, it is highly desirable to output the distance measurement or focus detection result quickly in terms of the operability of the camera. Therefore, it is necessary to make the calculation speed as fast as possible, so step #
The process proceeds from step 201 to step # 202, and the AF function writes the program in the flash memory having a high calculation speed.

On the other hand, if the function is not a function requiring a high calculation speed such as the AF function, the process proceeds to step # 203, and a memory (mask ROM or EEPRO) suitable for the function is used.
The function will be written in M).

As described above, the AF function can realize an easy-to-use camera with a small release time lag by storing the program in the memory (flash memory) having a high calculation speed.

In addition to this, as a function for which calculation speed is desired, there is a photometric function or the like.

(Third Embodiment) The operation for determining which memory is suitable for storing the program for executing the film feeding function of the various functions of the camera system having the above-described configuration is carried out by the present invention. The third form of the above will be described with reference to the flowchart of FIG.

The film feeding function requires rewriting such as film count (number of shots) information. In such a case, a rewritable memory is desired.

Therefore, when the storage destination memory is selected according to the flowchart of FIG. 4, step # 3
At 01, it is determined whether or not the film feeding function is a function that always operates. Since the film feeding function requires rewriting of data such as film count information, the program is written in the EEPROM having the characteristics shown in FIG.

On the other hand, if it is not necessary to rewrite the data like the film feeding function, the process proceeds to step # 303 to write the function in the memory (mask ROM or flash memory) suitable for the function. .

As described above, since the film feeding function requires rewriting of the film count information, the memory (EEPRO) which can withstand the number of rewritings among the memories.
By storing the program in M), it is possible to realize a film feeding function that does not forget the film count information even when the film is in the camera.

(Fourth Embodiment) The present invention relates to the operation of determining in which memory each program for executing the clock function, the film feeding function and the AF function of the camera system having the above-mentioned configuration is appropriate. A fourth embodiment of the present invention will be described with reference to the flowchart of FIG.

Considering the timepiece function first, the timepiece function keeps operating, as is well known, to count time. In such a case, in order to continue operation with a limited power supply for a long period of time, it is desirable to operate in a state where current consumption is as small as possible.

Therefore, when the storage destination memory is selected according to the flow chart of FIG. 5, first, at step # 401, it is determined whether or not the clock function is a function which always operates. Since the clock function is a function that always operates, the process proceeds from step # 401 to step # 404,
Here, it is determined whether data rewriting is necessary. The rewriting referred to here means data that needs to be stored even when the power is cut off. Since rewriting is not necessary, the process proceeds from step # 404 to step # 406, and the program is written in the mask ROM having the characteristics shown in FIG.

However, if it is desired to save the date and time data even when the power is cut off, step # 40
There is also a method of advancing from step 4 to step # 405 and rewriting the mixed programs in a plurality of memories.

As described above, the clock function requires constant operation, and it is desired that the power consumption be as small as possible. Therefore, the program is stored in the memory (mask ROM) which has the least operation power consumption among the memories. By doing so, a clock function with less battery consumption can be realized.

Next, considering the film feeding function, as is well known, the film feeding operates only when the film is loaded or after the photographing operation is performed. Further, the power consumption during operation is relatively high in consideration of bracing and the like because the DC motor or the like is driven to feed the film, but it does not fall to a low voltage. Furthermore, it is necessary to have a function that requires rewriting such as film count information. In such a case, an operation speed is not necessary, but it is desired that the rewritable memory be operable even at a low voltage.

Therefore, when the storage destination memory is selected according to the flow chart of FIG. 5, first, at step # 401, it is determined whether the film feeding function is a function which always operates. Since the film feeding function is not a function that always operates, steps # 401 to # 40
Proceed to step 2 to determine whether the calculation speed is required.
Since particularly fast signal processing is not required for film feeding, the process proceeds from step # 402 to step # 403, and it is determined whether the current consumption during operation is large and whether data rewriting is necessary. As described above, although the current consumption is large, it does not affect the power supply voltage and it is necessary to rewrite the film counter information and the like, so step # 403.
From step # 408, the film feeding function writes the program in the EEPROM having the characteristic that data can be rewritten.

As described above, the film feeding function may cause the power supply voltage to drop due to the driving of the motor, but it has no great influence. Also, since the film count information needs to be rewritten, the program is stored in a memory (EEPROM) that can withstand the number of times of rewriting, so that the film count information will not be forgotten even if the film is in the camera. The feeding function can be realized.

As with the film feeding function, there is a strobe control function as a function that does not require a calculation speed but consumes a large amount of current. In this case, step # 403.
Then, the process proceeds to step # 407, and the data is stored in a memory (flash memory) that can operate with a low voltage as much as possible.

Next, considering the AF function, the A
The F function is performed before the photographing operation, and particularly if it takes a long time to perform the calculation for calculating the distance measurement data or the focus detection data, it directly leads to the photographing time lag and misses the scene to be photographed. In such a case, it is desirable that the operating frequency is also high in order to increase the calculation speed.

Therefore, when the storage destination memory is selected according to the flow chart of FIG. 5, first, in step # 401, it is determined whether or not the AF function is a constantly operating function. Since the AF function is not a function that always operates, the process proceeds from step # 401 to step # 402, and it is determined whether a calculation speed is required. In the case of the AF function, it is highly desirable to output the result of distance measurement or focus detection quickly in terms of operability of the camera. Therefore, since it is necessary to make the calculation speed as fast as possible, the process proceeds from step # 402 to step # 407, and the AF function writes the program in the flash memory having a high calculation speed.

As described above, the AF function can realize an easy-to-handle camera with a small release time lag by storing the program in the memory (flash memory) having a high calculation speed.

Finally, the effects of each of the above-described embodiments will be summarized below.

As described in the first and fourth embodiments, the functions that must be constantly operating, such as the clock function and the switch monitoring function, are among the memories in the camera IC system. By storing (writing) a program for executing the function in a memory that can operate at low voltage and low power, for example, a mask ROM, it is possible to minimize battery consumption.

In other words, in the case of a function that must be operated at all times, it is necessary to enable the operation with the power consumption suppressed as much as possible, so the mask ROM with the lowest operation power consumption (low operation voltage) in the memory. The camera can be used for a long time by storing a program for executing the function in the.

Further, as described in the second and fourth embodiments, when the number of films in the film counter is stored every time the film is wound up like the film feeding function (the battery is loaded during film loading). Since the filming situation of the film will not be known if the camera is exchanged), the program that executes the function is stored in the memory in the camera IC system that does not disappear even if it is rewritten many times. By doing so, it becomes possible to remember the state of the camera.

That is, in the case of the function of rewriting the data in the memory frequently, the memory is not damaged or the data is not lost even if the data is rewritten frequently, for example, EEP.
By storing a program for executing the function in the ROM, it is possible to provide a safe and easy-to-use camera in which data on the use state of the camera is not lost.

Further, as described in the third and fourth embodiments above, when there are many operations such as autofocus (and photometry) and the operation is complicated, it takes time to control and the release time lag or the like is directly affected. If there is a connection and it affects the usability, store the program that executes the function in the memory with the fastest operation speed, such as flash memory, in the camera IC system to increase the computing speed. It is possible to make it faster.

In other words, in the case of controlling an operation that requires accuracy in the camera operation, the calculation speed is increased as much as possible, so that the function can be controlled in, for example, a flash memory even if the operation speed is fast. By storing the program to be executed, it is possible to perform highly accurate calculation, improve the calculation accuracy of the subject distance (and further the subject brightness), and take beautiful pictures.

According to each of the above-described embodiments, the optimum operating condition is set by switching the storage destination of the program for executing the function of the camera based on the relationship between the plurality of memories having different characteristics and the various functions. It will be possible. That is, various functions can be controlled under optimum conditions by appropriately switching the storage destination of the memory for storing the control program in accordance with the relationship between the operating current consumption, the number of rewriting endurance and the operating speed.

As a result, the specifications of the camera can be improved (the number of images that can be taken, the release time lag, usability, etc.),
A camera that is easy to handle, such as improved operability, can be provided.

In each of the above-described embodiments, the memory in which the program is stored is selected according to the operating characteristics of each function of the camera. It goes without saying that a part of the storage memory may be changed.

Although the camera is taken as an example, the present invention is not limited to this, and the operating current consumption, operating speed,
It can also be applied to a system having a plurality of memories having at least one of the rewriting endurance numbers having different characteristics and a system having various functions having different operation characteristics (current consumption, operation speed, etc.).

[0065]

As described above, according to the present invention,
A program storage system or camera capable of controlling various functions under optimum conditions by appropriately switching the storage destination of the memory for storing the control program in accordance with the relationship between the operating current consumption, the number of rewriting endurance and the operating speed. Can be provided.

Further, according to the invention described in claim 1 or 8, in the case of a function which must be operated at all times, since the operation of which the power consumption is suppressed as much as possible is required, the power consumption is suppressed even in the memory. By storing the program for executing the function in the memory, the system or the camera can be used for a long period of time.

According to the invention described in claim 3 or 8, in the case of a function that requires frequent rewriting of data in the memory, the memory may be damaged or the data may be lost even if rewriting is frequently performed. By storing a program for executing the function in a memory that does not disappear and has a high number of rewrite endurance, it is possible to make a safe or easy-to-use system or camera in which the data in the usage state does not disappear. .

Further, according to the invention of claim 5 or 8, in the case of a function requiring accuracy among various functions, control can be performed even if the operation speed is high in order to increase the calculation speed as much as possible. By storing a program for executing the function in the memory, a system or a camera that enables highly accurate calculation can be provided.

[Brief description of drawings]

FIG. 1 is a block diagram showing a main configuration of a camera IC system according to each embodiment of the present invention.

FIG. 2 is a flowchart showing a function according to the first embodiment of the present invention and an operation of selecting a memory of a storage destination.

FIG. 3 is a flowchart showing a function and a memory selection operation of a storage destination according to the second embodiment of the present invention.

FIG. 4 is a flowchart showing a function and a memory selection operation of a storage destination according to the third embodiment of the present invention.

FIG. 5 is a flowchart showing various functions according to a fourth embodiment of the present invention and an operation of selecting a storage destination memory.

FIG. 6 is a diagram showing operating voltage-operating frequency characteristics of the mask ROM according to each embodiment of the present invention.

FIG. 7 is a diagram showing operating voltage-operating frequency characteristics of the flash memory according to each embodiment of the present invention.

FIG. 8 is a diagram showing operating voltage-operating frequency characteristics of the EEPROM according to each embodiment of the present invention.

[Explanation of symbols]

1 One-chip microcomputer 2 AF circuit 3 AE circuit 4 Shutter control circuit 5 SW circuit 6 DC / DC circuit 7 Strobe circuit 8 oscillator circuits 9 Display control circuit 10 Motor control circuit

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) G06F 12/16 310 G06F 9/06 650L (72) Inventor Koji Oshima 3-30-2 Shimomaruko, Ota-ku, Tokyo No. Canon Inc. (72) Inventor Masanori Otsuka 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Yasuhiro Harada 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. In-house F-term (reference) 2H020 ME21 2H100 FF01 FF08 5B018 GA04 GA10 HA04 NA06 5B060 MM03 5B076 AB19

Claims (8)

[Claims] 1. A program storage system having a plurality of memories having different operating current consumptions and storing a control program in any one of the plurality of memories for each function, wherein A program storage system characterized in that a program for executing necessary functions is stored in a memory that can reduce current consumption. 2. The program storage system according to claim 1, wherein the function that requires constant operation is a clock function. 3. A program storage system having a plurality of memories having different rewriting endurance times and storing a control program for each function in any one of the plurality of memories, wherein data in the memory is stored every time a predetermined operation is performed. A program storage system characterized in that a program that executes a function that needs to be rewritten is stored in a memory that has a large number of rewriting endurance times. 4. A program used for a camera, wherein a program for executing a function that requires rewriting data in a memory each time the predetermined operation is performed is a film feeding function of the camera. The program storage system according to claim 3. 5. In a program storage system having a plurality of memories having different operation speeds and storing a control program for each function in any one of the plurality of memories, the program for executing a function requiring accuracy is: A program storage system characterized by storing in a memory that can operate at high speed. 6. A program which is used for a camera, and which executes a function which requires the accuracy,
The program storage system according to claim 5, which is an autofocus function of a camera. 7. A program storage system having a plurality of memories each having different operating current consumption, number of rewriting endurance, and operating speed, and storing a control program in any of the plurality of memories for each function. For the programs that execute the functions that require constant operation, the programs that are stored in the memory that can reduce the current consumption are not stored in the memory programs. The program that executes the function that needs to be rewritten is stored in a memory that has a large number of rewrite endurance times, and it is not the function that requires the constant operation and the function that needs to rewrite the data in the memory every time the predetermined operation is performed. For programs that execute functions that require precision, store them in a memory that can operate at high speed. Characteristic program storage system. 8. A camera equipped with the program storage system according to claim 1. Description: