JPH0270179A - Camera provided with auto-power-off function - Google Patents

Abstract

PURPOSE:To intend power-saving and the improvement of operability by starting time counting when a switch for power supply and photographing or its preparation and the switch for the drive control of an optical system are operated, and cutting off power automatically after prescribed time elapses. CONSTITUTION:When a main power source is turned on by the switch 16, the counter of a system control device 10 starts the time counting, and it clears counted time till then in response to input by the switches 11 to 15, and starts again the time counting from zero. Then, when the counter counts definite time, the device 10 turnes off the main power source, and shifts into a standby mode. Besides, when the control data of the optical system such as power zoom, stroboscope, etc., is sent to the device 10 from a photographing control device 30 and a recording control device 70, a prescribed count value is set in the counter, and the time counting is started again from zero. Thus, the operability for auto-power-off in the camera adopting multi-CPU system is improved.

Description

[Detailed Description of the Invention] Summary of the Invention A main CPU having an auto power-off function and a sub-CPU that shares drive control of optical systems such as power zoom and power focus are connected so as to be able to communicate with each other. .

The main CPU is always running, but the sub CPU
is in standby mode to save power. power·
When there is a drive switch input such as zoom, power/focus, etc., the sub CPU is activated and the main CPU is notified of this. In response to this, the main CPU starts the timekeeping operation in the auto power-off operation from +Ij and the lightest.

BACKGROUND OF THE INVENTION This invention relates to a camera with an auto power off function.

Recently, the functions of cameras have been diversified, and the number of control items is increasing. In addition to automatic exposure control, power zoom,
These include support for power focus, single shooting, continuous shooting, self-timer, and manual exposure settings. In particular, still images captured and displayed using a solid-state electronic image sensor such as a CCD
A type of still camera that records video signals on a magnetic disk.
Video cameras (electronic still cameras) also require control of the rotation of the magnetic disk, control of the movement of the magnetic head, and the like.

These controls are often performed by a CPU these days, but as the number of control items increases, it becomes impossible for a single CPU to control them. Therefore, it is desirable to adopt a system in which ha-controlling functions are shared among multiple CPUs. Generally multi CP
In the U system, one main CPU is connected to one sub-CPU or 7M1 sub-CPUs, and they share various functions of the camera while communicating with each other.

Several problems arise when such a multi-CPU system is employed in a camera.

One of them is the issue of power saving. When one or several CPUs are operated, power consumption increases. -Noj. Cameras are desired to be smaller and lighter, and for this reason, it is necessary to use a smaller battery as a power source.
Aiming for power saving in cameras is an important issue.

Another problem is the mutual cooperation between the main CPU and sub-CPU in a multi-CPU system. Some operation is performed in a part for which the main CPU does not share the function, and the main CPLI may also be required to perform some operation in connection with this operation.

For example, in connection with the above-mentioned power saving, there is an auto power off function. Generally speaking, this function automatically turns off the main power if the main power is on and the switch related to shooting is not pressed for a predetermined period of time, assuming that there is no intention to operate the camera. It can be said that this is a function that can be turned off. In a multi-CPU system, if this auto power off function is shared with the main CPU, and the auto power off function is activated only in response to the switch attached to the main CPU, the auto power off function will not respond to the switch attached to the sub-CPU. In this case, a problem arises in that the main power supply is suddenly turned off while the sub CPU is operating. From another perspective, this problem may be said to arise from automating what was previously a manual operation. There is a danger that automation may actually worsen operability.

Summary of the Invention The present invention provides a camera that employs a multi-CPU system, particularly in relation to an auto power off function.
We aim to improve power efficiency and operability.

A camera with an auto power-off function according to the present invention has a main control device including a main CPU that supervises overall control for photographing in the camera and also controls power on and off, and at least a main control device that controls the optical system. It is constructed by connecting a sub-control device including a sub-CPU that performs drive control so that they can communicate with each other.

While the power is on, the main control device is in operation, and the sub-control device is in a standby state after initial operation, and when there is a command from the first control device, it responds as needed. perform an action.

The main control device starts a timekeeping operation in response to input signals from the power switch and the first switch operated for photographing or preparing for the shooting, and from the power switch and the first switch. an auto power-off control means comprising a timer for detecting that a predetermined period of time has elapsed without any switch being operated; and a means for turning off the power when the timer detects the elapse of the predetermined interval. We are prepared.

According to this invention, the sub-control device includes a second switch that is operated before photographing to input a command for drive control of the optical system, and an interrupt signal based on the input from the second switch. The main controller transmits a signal indicating that the second switch input has been made to the main controller, and the main controller uses the clocking means when it receives a signal from the sub-controller that there is a second switch input. The present invention is characterized in that it further includes a control means for starting a timekeeping operation.

According to this invention, in a multi-CPU system that includes a main CPU and at least one sub-CPU, while the power is on, the sub-CPU is in a standby state after its initial operation, thereby saving power. can be achieved. Moreover, since the main CPU has an auto power off function, power saving can be achieved even more efficiently.

On the other hand, even if the sub CPU is in a standby state, if there is a switch input to the memory 2, it is activated by an interrupt based on this and notifies the main CPU of this fact. Main CP
When U receives notification that there is a second switch input,
The timekeeping operation of the timekeeping means in the auto power-off control means is restarted from zero. In this way, the auto power-off control means is controlled in response to the input from the second switch, which the main CPU including the auto power-off control means does not directly control, so that the main CPU including the auto power-off control means can control the operation. The operator can operate the second switch for driving and controlling the optical system without worrying about the auto power off operation, and what is more, the main power supply can be turned off automatically while the optical system is being driven. It does not turn off when the power is turned off.

In this way, in addition to saving power, it is possible to improve operability.

An embodiment in which the present invention is applied to a still video camera will be described in detail below, but the present invention is also applicable to general silver halide cameras.

Furthermore, in the following embodiments, a so-called power zoom is shown as an example of drive control of the optical system.

The present invention is also applicable to other drive controls such as power focus.

DESCRIPTION OF THE EMBODIMENTS FIG. 1 shows the system configuration of a still video camera.

This still video camera has three controllers: system controller 10. It is controlled by the photographing control device 30 and the recording control device 70. These control devices to
, 30.70 each consist of a CPU (for example, a microprocessor), a memory (RAM, ROM, etc.) for storing its programs and necessary data, and necessary interface circuits. The CPU of the system control unit IO is the main CPU, and controls the overall operation of the still video camera. As described later,
While the main power is on, press the various switches 11 to 15 on the camera.
etc. is not operated continuously for a predetermined period of time (for example, 8 minutes), the main power of the camera is turned off by the auto power off operation of the system control device 10. A counter is provided for this purpose. This counter can also be implemented by using a predetermined area of memory for counting. The CPUs of the photographing control device 30 and the recording control device 70 are sub-CPs.
It's U.

It operates according to commands from the main CPU.

The photography control device 30 performs photography-related controls such as power focusing, aperture, shutter speed, power zoom, and strobe control. The recording control device 70
Driving the motor 3, loading/unloading the magnetic head 2,
It controls the recording of video signals on the video floppy disk 1, such as the movement of the magnetic head 2. These control devices 10, 30, and 70 are interconnected by a plurality of serial transmission lines, and communicate at predetermined timings.

A regenerator (regeneration adapter) 90 can also be connected.

This regenerator 90 demodulates the video signal read from the video floppy disk 1, converts it into a color video signal in, for example, NTSC format, and outputs the converted signal. Recycled product 90
Also includes a CPU and memory, and this CPU is positioned as a sub-CPU to the main CPU.

A still video camera has a packet that can be opened and closed, and the video floppy 1 is inserted into the opened packet, and when the packet is closed, the video floppy 1 is inserted into the disk motor. It is chucked on the spindle of No. 3.

The video floppy 1 is provided with a number of concentric tracks (for example, 50) (for example, a track pitch of 100 μm), and depending on the shooting process, one or two tracks are provided.
1 field or 1 frame (1 frame) per track
An FM-modulated color video signal (including a luminance signal, color difference signal, etc.) is magnetically recorded. The 50 tracks arranged concentrically on the magnetic recording surface of the video floppy 1 are numbered in order from the outermost ones: No, l=No, 50
The track number up to this point has been cut off. Home fist position HP (origin position or standby position) is No. 1
on the outside of the trunk, and the end position EP is N.
o, inside the trunk of 50.

The system control device 10 includes a power switch 1G, various mode switches 11 to 14. Shutter release - switch input signal such as button 15, detection signal of bucket switch 7 that detects the open/closed state of the packet containing the video floppy (and presence or absence of the video floppy if necessary), installation location of the video floppy 1 The humidity in the vicinity is a
A detection signal from the dew condensation sensor 8, etc., which determines the temperature, is input. The modes that can be set include frame/field mode that indicates frame recording or field recording, skip mode that creates empty tracks that are not recorded on the video floppy, edit mode that records on empty tracks, and J! ! There are drive modes for setting photo or single shot, 2 high-sensitivity and slow shooting modes, etc. These set modes, track number to record,
, and other information are displayed on a liquid crystal display 21, which will be described in detail later. This display 21 is connected to the system control device 10 by bus. Further, when dew condensation is detected or other abnormal conditions occur, the buzzer 22 sounds an alarm.

The power switch 16 is of a push button type, and when pressed, a pulsed switch-on signal is input to the main CPU of the system control device 10 as an interrupt signal.

The shutter release button 15 is of a two-stage stroke type, in which the first stage of depression releases switch S1, and the second stage of further depression of the button 15 causes switch S2.
are respectively turned on. When switch S1 is turned on, disk motor 3 is driven. After this, switch S2
When turned on, photographing and recording are performed.

The imaging optical system includes a zoom lens system 31. An imaging lens system 32 for forming a subject image. Aperture 33. A beam that is deflected in order to make a part of the incident light enter the photometric element 51.
Splitter 34. It is composed of an infrared cutoff filter 35 and a shutter 3G. The illuminance detection signal of the Jpj optical element 51 is input to the photographing control device 30 via a logarithmic amplifier 52. By the shooting control device 30.

A process of calculating the aperture value and shutter speed based on the incident light illuminance detected by the photometric element 51, control of the aperture 33 based on the determined aperture value, and opening/closing control of the shank 36 based on the similarly determined shutter speed are performed. . The aperture 33 is opened and closed by an aperture motor 48 driven by a driver 47.

A switch 49 for detecting the opening and closing limit positions of the diaphragm 33 is also provided. First curtain of shutter 36.

The unlatching and winding of the trailing curtain is performed by a shutter drive including a shutter motor 54 driven by a driver 53. The rotation angle of the motor 54 is detected by a rotary encoder 55 and fed back to the device 30.

The color detection signal from the color sensor 61 is subjected to predetermined processing in a white balance processing circuit 62 and then input to the device 30 . This white balance data is applied to the R in the variable gain amplification circuit described later in the signal processing circuit 71.
, G, and B signals for amplification gain control.

In order to determine all distances to the subject, an infrared light emitting diode 63 and a light receiving element 64 that receives the reflected light are provided.Based on the output signal of the light receiving element 64, a focusing processing circuit 65 determines the distance to the subject. Data representing distance is obtained. Using this data, the auto focus motor 4 is controlled via the driver 45 to control the device 30.
B is driven and power focusing control is performed.

Additionally, tele to enter the zoom culm.

In response to signals from the wide switches 38 and 39, the control device 30 drives the zoom motor 42 via the driver 41 to set a predetermined magnification (power zoom). The rotation angle of the motor 42 is detected by a rotary encoder 43 and fed back to the device 30.

This still video camera can be equipped with a strobe device 66 so that it can take pictures in dark areas. When the strobe device 66 is attached to the camera, its terminal is brought into contact with a terminal 67 provided on the camera body, so that it is electrically connected to the photographing control device 30. Charging starts when the power switch 66a of the strobe device 66 is turned on, but a signal indicating that the switch 66a is turned on (strobe on signal) or switch 6G
A signal indicating that a is turned off (a strobe off signal) is input to the photographing control device 30 through the above terminal. When the switch S2 of [shutter release button] 5 is turned on and photographing is performed when predetermined conditions are met, the strobe device 66 A light emission command is given to the strobe device 66, and the strobe device 66 emits light.

At the focal plane of the imaging optical system, a solid-state electronic imaging device 37 for three primary colors, which is composed of a two-dimensional imaging cell array such as a CCD, is arranged.

The image data accumulated in the imaging device 37 when the shutter 3G is opened is converted into a serial still video signal (R, G, B) in synchronization with the vertical and horizontal dot signals given from the signal processing circuit 71. The signal is read out and input to the signal processing circuit 71.

The signal processing circuit 71 includes an oscillation circuit, and generates and outputs a vertical reference signal VD and a reference clock signal from the output signal of the oscillation circuit. The vertical reference signal VD is supplied to the system controller 10. It is given to the photographing control device 30 and the recording control device 70, and serves as a reference for the operation timing in these devices. The reference clock signal is provided to the servo control circuit 80. As will be described later, the phase pulse PC representing the reference phase of rotation of the video floppy 1 is transmitted to the signal processing circuit 71.
System control device IO9 recording system? :8 device 70 and regenerator 90. A reset signal given from the recording control device 70 adjusts the vertical reference signal VD in the signal processing circuit 71 so as to maintain a constant phase relationship with the phase pulse PC. The signal processing circuit 71 also generates vertical and horizontal synchronizing signals having a constant phase relationship with the phase pulse PC.

The signal processing circuit 71 further includes a preamplification circuit for input still video signals (R, G, B), a variable gain amplification circuit (white balance adjustment circuit), and a process matrix circuit. In the process matrix circuit, a luminance signal Y and two color difference signals R-Y, B
-Y is created. These color difference signals R-Y, B-Y
is then line-sequentialized for each IH in a line-sequentialing circuit 72.

The luminance signal Y and the line-sequential color difference signal pass through a pre-emphasis circuit (not shown), are FM-modulated in different frequency bands in FM modulation circuits 73 and 74, and are combined in a two-combination circuit 75.

Furthermore, data multiplex recording is also possible on video floppies. This multiple recorded data includes initial bits, field/frame data, and track addresses (No.
, ) data, date data, and user usage data. These data are given from the system control device 10, and the signal processing circuit 71 processes them as D P S K (D
ir['erential PhaseShlft K
eying), is combined with the above-mentioned FM modulated video signal in a combining circuit 7G, and is input to a recording amplifier circuit 77.

A magnetic head 2 (
To enable frame recording, the floppy disks (two floppy disks are provided at intervals on adjacent tracks) are supported movably in the radial direction of the video floppy disk 1 by the transfer drive control device, and are moved in the same direction. Transport controlled. This transfer drive control device includes a step motor 87 and its dry nozzle (86).
provides instructions to the transfer drive controller regarding the transfer horn direction and transfer state. Magnetic head 2 is at home position H
A home Φ position switch 6 is also provided for detecting that P has been reached, and this switch 6 detection signal is given to a recording control device 70.

A video load device is provided to prevent marks from being formed on the floppy due to long-term contact of the magnetic disk 2 with the video floppy 1 when it is stopped. This device includes a head load solenoid 85 and its dry nozzle (84), and includes a recording control device 70.
Under the control of At other times, the magnetic head 2 is displaced (backward) away from the floppy disk 1. As will be described later, the magnetic head 2 is also evacuated from the video or floppy disk 1 when the main power is turned off by auto power-off control.

In order to improve the contact between the magnetic head 2 and the rotating video floppy disk 1, a regulating member (not shown) is provided on the opposite side of the magnetic head 2 with the video floppy disk 1 in between. In addition, the core of Video Floppy 1 includes:
Detect leakage magnetic flux of permanent magnet for chucking and record video
A position detector 5, which outputs a phase detection signal when the floppy disk 1 reaches a predetermined angular position, is nearby. The output detection signal of the phase detector 5 is waveform-shaped by a phase pulse generation circuit (waveform shaping circuit) 82 and outputted as a phase pulse PG. It is input to circuit 71 and recording gate circuit 78 . One phase pulse PC is generated for each rotation of the video floppy 1.

The disk motor 3 is driven by its driver 81. The rotational speed of the disk motor 3 is detected by a frequency generator 4 and output from this frequency generator 4.

A detection signal with a frequency proportional to the rotation speed of the motor 3 is input to the servo control circuit 80. The servo control circuit 80 rotates the motor 3 at a constant speed based on the reference clock signal input from the signal processing circuit 71 and the frequency detection signal input from the detector 4. I (e.g. 3.600r, p, I
m, ) to rotate at a constant speed. Also the servo control circuit 80. The motor 3 is started and stopped in accordance with commands from the recording control device 70.

The still video signal etc. amplified by the recording amplifier circuit 77 is input to a recording gate circuit 78. and recording control device 7
When a recording command is given from 0, this gate circuit 78
opens its gate at the timing of the input phase pulse PG until the next phase pulse is input. As a result, video signals and the like are applied to the magnetic head 2, and recording of still video signals and the like onto predetermined tracks of the video floppy disk 1 is performed. This recording is performed only during one revolution of the video floppy. This is the case for field recording. Gate circuit 78 in case of frame recording
opens its gate for two revolutions of the video floppy 1, and in the first revolution of the video floppy 1 the video signal of the first field l' is transferred to a certain track by one head 2, As the head 2 rotates, the video signal of the second field is recorded in the adjacent track by the other head 2, respectively.

It is also possible to reproduce video signals etc. from the video floppy disk 1 using the magnetic head 2. The FM modulated video signal etc. read from the magnetic head 2 similarly passes through a gate circuit 78 and is amplified by an amplifier circuit 77 and sent to an envelope detection circuit 8.
3 and regenerator 90. This reproduction is used for track search processing not only in the reproduction mode but also in the recording mode.

The envelope detection circuit 83 detects the read signal of the magnetic head 2, that is, the envelope of the FM modulated video signal recorded on the track of the video floppy 1.
This is a detection circuit that detects the voltage and outputs a voltage signal according to the detection, and includes an A/D (analog/digital) conversion circuit. The voltage signal representing the envelope is converted into a digital signal by an A/D conversion circuit, converted into an 8-bit digital signal representing, for example, 256 quantization levels, and input to the recording control device 70.

The envelope detection signal is used by the recording control device 70 to determine whether a track on the video frame 1 is unrecorded or recorded (track search processing).The magnetic head 2 is moved across the track. If the level of the detected signal does not reach the predetermined threshold φ level when the track is transferred as shown in FIG.
If the Threnholt level has been reached, the track has been recorded.

If necessary, the envelope detection signal is also used in the recording check process. The recording check process is to check whether the recorded still/video signal has been recorded on a predetermined track using the magnetic head 2 as described above, and whether the envelope detection signal is in the predetermined range. If it is above the Threnhold level, it is determined that recording has taken place.

The still video camera is further equipped with a power supply circuit 110. The power supply circuit 110 includes a main power source (battery) i
ll and an auxiliary power source (battery) 112 are provided. The main power supply 111 supplies all electrical power for the still video camera.
, which supplies operating power to the components. The auxiliary power supply 112 supplies operating power to the main CPU of the system control device 10 when the main power supply 11 is off (that is, the main power control switch 113 described later is off).
At this time, the main CPU is in standby mode. Therefore, the main type i[ill and the auxiliary power supply 112 are connected in parallel to the system control device IO. A main power control switch 113 is connected to the output side of the main power supply 111. This switch 113 is the system controller IO
is turned on when a switch signal is input from the power switch 16, and when the system controller 10 and the regenerator 90 are connected to each part of the still video camera and the voltage adjustment circuit 114, the regenerator 90 is turned on. Power is supplied from the main power supply ill. Furthermore, if the power switch 16 is pressed while the switch 113 is on and a switch signal is input to the system control device 10, the system control device 10 turns off this switch 113, and the still/video camera and playback The main power supply to the device 90 is stopped. Further, when the switch is not operated for a predetermined period of time, the system control device 1
The main power control switch 113 is turned off by the auto power-off operation by 0.

The sub CPUs of the control devices 30 and 70 are connected to the power switch 1
6 is activated by the system controller 10 when a switch-on signal of 6 is input to the system controller 10.

When activated, the photographing control device 30 opens a barrier for protecting the lens present in front of the lens, sets the aperture 33 to the home position (for example, the open position), and further opens the zoom lens system 31 and the imaging lens system. 32 to their respective home positions (initial processing).

After this initial processing operation, the sub CPU of the photographing control device 30
enters standby state. Sub CP of recording control device 70
U also performs initial processing in the same way, and then enters the standby state. The main CPU of the system control device 10 continues to be in an operating state.

The regenerator 90 is removably attached to the main body of the still video camera. When the regenerator 90 is attached to a still video camera, the power supply lines from the main power supply 111 and the auxiliary power supply 112, the reproduced video signal line from the recording amplifier circuit 77, the phase pulse PC line, and the serial transmission line are connected to the regenerator 90. is connected to the same line on the regenerator 90 side by a connector (not shown).

As described above, the main CPU of the system control device 10 is in standby mode when the main power control switch 113 is off, but is activated when an interrupt signal from the power switch 1G is input, and turns on the switch 113. shall be.

Figure 2 shows the liquid crystal display 21 and mode switches 11 to 14.
It shows. The liquid crystal display 21 has two date display areas A,
Exposure stop display section B, drive mode display section C, manual exposure mode display section 1, l-rack\03 front bottom section E
, and other display sections (these are left blank as they are not particularly relevant to this embodiment). The date display section A displays the year, month, and day of the day, as well as the exposure fli iF and the value (0, 0,
5, 1, 0, 2, 0, etc.) are displayed. Exposure compensation display section B shows that the exposure compensation value displayed on date display section A is positive (+).
or negative (-) is displayed. Positive (+) in Figure 2
is displayed. Drive mode display section C has characters representing self-timer, single-shot mode (S), and quick-shot mode (C), and a line a is displayed above the character representing the currently set mode. Ru.

High sensitivity mode is displayed on the manual exposure mode display area.
There are display characters such as "GllJ", "normal mode", and "slow mode rsLOWJ", and a line a is displayed above the character representing the set mode. High sensitivity mode is a mode that doubles the amplification gain of still video signals, allowing for faster shutter speeds. Slow mode is a mode in which the aperture is opened and the shutter speed is fixed at 1/23cc. The normal mode means the normal automatic exposure side 1III (including flash photography control).

Each of the mode setting switches (buttons) 11 to 14 has many setting functions singly or in combination. Switch 11 is a clock and function switch, and when this switch 11 is pressed alone, the display with 11
The time is displayed. Further, the switch 12 is an exposure compensation/field/frame mode setting switch. When this switch 12 is pressed alone, the exposure compensation value is displayed in place of the date etc. on the 1 display section A, and depending on the combination with the + or 1 display on the 1 display section B, each time the switch 12 is pressed, the exposure compensation value or O, +0.5, +1. O, +2.0, -0
．． It changes cyclically in the order of 5. This exposure correction value is a value that is added to or subtracted from the exposure value Ev used in a program diagram used in automatic exposure control that determines the aperture value and shutter speed. If switch 12 is pressed while switch 11 is pressed, the field mode and frame mode are alternately switched each time the switch 12 is pressed. Switch 13 is used for white balance adjustment and operation mode (normal mode, skip mode, edit mode, etc., these are displayed in blank spaces on display aH21).
Used for switching. Switch I4 is an operation mode/manual exposure mode setting switch. This switch I
If you press 4 alone, each time you press 4, the drive φ mode setting changes to self-timer, single shot mode (S), and quick shot mode (
C). Also, if you press this switch 14 while pressing the switch 11, the shooting mode changes to the high sensitivity mode each time it is pressed.

It is switched cyclically in the order of normal working mode and slow mode.

Setting and changing of various modes as described above are executed by the main CPU of the system control device 10.

FIG. 3 shows the auto power-off processing procedure performed by the main CPU of the system control device IO. This process, especially the process of decrementing (-1) the contents of the counter, is performed at regular intervals (for example, every 250 m5).

The auto power off process turns off the main power if there is no input from switches 11 to 15 for a certain period of time (8 minutes in this example) after the main power is turned on by switch 16. Main CPU or standby
This is the process of moving to the mode. The above-mentioned fixed time is measured by a counter of the system control device. This counter responds to inputs from the switches 11 to 15, clears the time measured up to now, and starts counting again from zero. When the counter measures the predetermined time, the main CPU turns off the main power in response.

The time measured by the counter is cleared not only when switches 11 to I5 but also when the zoom operation switches (tele and wide switches 38° and 39) are pressed, but this is related to Fig. 4. I will explain.

The auto power off process is started when a switch-on signal from the power switch 16 is input to the system control device 10 (step 121), and a count value corresponding to the predetermined time is set in the counter (step 122). ). If the predetermined time is 8 minutes and the counter is decremented by 1 count every 250 m5, the set count value is 8 x 60/ (250 x 1
O-3) -1920. If there is no key operation (switches 11 to 15) of the camera described above (step 123
If No>, the value of the counter is decremented by one count to 2.50 ts s (step 124). When a key operation is performed, the above count value is set in the counter again (step 122).

When no key operation is performed for 8 minutes and the counter value reaches 0 (step 125), the main power switch 113
is turned off, and the main CPU enters a standby state (step 12G). At this time, that is, switch 11
Just before 3 is turned off, head rotor solenoid 8
5 is driven by a driver 84 to retreat from the magnetic head 2 or video floppy disk 1.

FIG. 4 shows that after the power switch 1G is turned on and the sub-CPU of the photographing control device 30 enters the standby state as described above, the preparation operation for photographing is performed in the portion that the photographing control device 30 is responsible for. It shows the processing that is performed in response to something that has been done. In this embodiment, the preparation operations for photographing include the fact that the strobe device 66 is attached to the camera and its power switch 66a is turned on (off) (strobe on, strobe off), and that the power zoom is turned on. This means that the tele and wide switches 38 and 39 were turned on (zoom on). switch O
[IA on signal or off signal, switches 38, 39
The on-signal from the sub-CPU is given as an interrupt signal to the sub-CPU of the photographing control device 30, whereby the sub-CPU is activated from the standby state and performs the operation shown in FIG.

The sub CPU is the main CPU of the system control unit ■0.
If this communication request is accepted, the strobe is turned on (step 131) when there is an interrupt from the switch 68a.
or off).

When there is an interrupt from the switch 38 or 39, data indicating zoom on is sent to the main CPU (step 132), and in the case of a strobe on signal, the system returns to the standby state again (step 1: +3> .

After this, in the case of a zoom-on signal, the driver 41. The zoom operation is controlled by the motor 42 (step 134).

After the main CPU receives a request signal from the sub CPU (YES in step 141), when it receives some data, it determines whether it is strobe-on data or zoom-on data (step 142, 143).

If the received data is strobe-on data (YES in step 142), and if exposure compensation is being performed by switch 12, the exposure compensation value is cleared (that is, set to O) (step 14G). This is because flash photography does not use a program diagram to determine the aperture value and shutter speed.

This is because exposure compensation is also unnecessary.

Furthermore, if the operation mode is set to the quick-shot mode by the switch 14 (YES at step 147), the flash operation of the strobe device 66 cannot follow the continuous shooting operation in the quick-shot mode, so the mode is changed to the single-shot mode ( Step 148). Furthermore, if the shooting mode is set to either high sensitivity mode or slow mode by switch 14 (YES at step +49),
Since these modes are inappropriate for strobe photography, the mode is changed to normal mode (step 150).

Furthermore, settings such as continuous shooting mode and high sensitivity mode are canceled (step 151). Then, the set single shooting mode, normal mode, is displayed on display section C of the liquid crystal display 21.
and displayed on the display. If necessary, a strobe attachment indication may be provided on the display 21.

As described above, when the strobe device 66 is attached and its power switch 66a is turned on, the main C
A mode suitable for flash photography is set by the PU.

If zoom-on data is sent from the sub CPU (Y IES' in step 143),
The above-mentioned predetermined count value (1
920) is set (step 144). As a result, the time counting operation by the counter is restarted from zero. This prevents the main power source from being turned off by auto power off when the photographing control device 30 performs a power zoom operation.

If the received data is not zoom-on data, it is strobe-off data (No at step 143).
, the prohibition settings for continuous shooting mode, high-sensitivity mode, etc. in step 151 are canceled (step 145).

The switch input for restarting the 1 o'clock operation of the counter for auto power off operation is not only the zoom on signal mentioned above, but also the input for focusing drive in a camera with a power focusing function. It might be a switch input signal or something. This power focusing is also done not by the main CPU but by the sub CPU.
In many cases, it will be controlled by

In the above embodiment, a still video camera to which a strobe device can be attached is explained, but when applied to a still video camera, the present invention can also be applied to a camera to which a strobe device cannot be attached. be. In that case, step 13 in the flowchart of FIG.
2 and steps 136 to 142 are no longer necessary.

[Brief Description of the Drawings] Figure 1 is a block diagram showing the system configuration of the still video camera, Figure 2 is a diagram showing the display and mode setting switch, and Figure 3 is the auto power off processing procedure. Figure 4 is a flowchart showing the sub CPU and main CPU based on strobe shooting preparation and zoom switch input.
It is a flowchart which shows the processing procedure in PU. 1(]...System control device. 11-14...Various switches. 16...Power switch. 30...Photography control device. 38...Tele switch. 39...Wide switch. 66 ... Strobe device. 88a ... Strobe power switch. II+ ... Main power supply. Above is Figure 2

Claims (1)

[Scope of Claims] A main control device that performs overall control for photographing in the camera and controls power on and off, and a sub-control device that controls at least the drive of the optical system communicate with each other. The main controller is in operation while the power is on and the secondary controller is in standby mode after initial operation, and when a command is received from the first controller. The main control device includes a power switch, a first switch that is operated for shooting or preparation, and a control unit that controls the power switch and the first switch. a timekeeping means that starts a timekeeping operation in response to an input signal and detects that a predetermined time has elapsed without the first switch being operated; and a timekeeping means that turns off the power when the timekeeping means detects that the predetermined time has elapsed. The sub-control device is equipped with a second switch that is operated before photographing to input a command for driving control of the optical system, and the second switch is It is activated by an interrupt signal based on the input from the switch, and transmits to the main controller that there is a second switch input, and the main controller receives a notification from the sub controller that there is a second switch input. A camera having an auto power off function, further comprising control means for starting a timekeeping operation by the timekeeping means when a signal is received.