JPS62166323A - camera memory circuit - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] (Technical field) The present invention relates to a memory circuit for a camera.

(Prior art) When a memory section for storing camera information is provided in a main body that controls the camera's shutter, motor, etc., when the main body's power supply voltage drops or the main body's power is turned off, the memory section stores information. Content will be lost. Therefore, measures must be taken to add a function to back up the main unit's power supply and to prevent the main unit from being turned off at all times. However, the main body of the camera has various loads, and there is a limit to how much current consumption can be suppressed, so if you want to back up the power supply, you will need something with a large capacity. Furthermore, if the power is not turned off at all times, a large amount of current is consumed and the battery is wasted, and information may be lost due to a sudden drop in power supply voltage.

(Objective) It is an object of the present invention to provide a memory circuit for a camera that can improve the above-mentioned drawbacks, reduce power backup capability, suppress battery consumption, and prevent information loss.

(Structure) According to the present invention, a storage means is provided in the liquid crystal display driving section of a camera, and camera information from the main body is stored in the storage means so that it can be read from the main body. The liquid crystal display driving section is configured to be constantly driven at a voltage lower than the source voltage of the main body, or so that the power source of the liquid crystal display driving section is backed up.

FIG. 1 shows an embodiment of the invention.

This embodiment is a camera in which the main body of the camera, which controls the shutter, motor, etc., and the liquid crystal display drive section, which displays various camera information, are separately provided.

An output register 1 is provided as a storage means within the liquid crystal display driver. The main body of the camera serially transfers various information SI of the camera to be displayed to the liquid crystal display drive section, and at the same time transfers the reference clock SCK and chip select signal C8. In the liquid crystal display drive section, the input shift register 2 receives information SI and clock SCK from the main body via buffers 3 and 4, and stores the information SI. - As an example, the input register 2 has an 8-bit configuration, and the information SI is transferred and stored in 8-bit units to the next-stage latch sections 51 to 5n. In this case, the clock SCK from the main body is counted by the counter 6 via the buffer 4, and the latch/register control section 7 is controlled by the input shift register by the chip select signal input from the main body via the buffer 8 and the output signal of the counter 6. 2 and latch portion 51~
The stored information of 5n is displayed on the display section 1 by the display control section 9.
Displayed as 0. The output register 1 receives the information output from the input shift register 2, and the last 8 bits of information SI from the main body remain. In this case, the latch/register control unit 7 stores the information transferred from the input shift register 2 to the latch units 51 to 5n in the output register 1 each time (or detects the last 8 bits and stores it in the output register 1). ). Therefore, if the information to be stored in the main body is placed at the end of the information SI, that information will be stored in the output register 1'. This output register 1 serially outputs the stored information to the main unit via the buffer 11 when the next 8 bits are input.
The main body can read information from the output register 1 by transferring the next display information SI or dummy information to the liquid crystal display driver. The liquid crystal display drive unit uses a liquid crystal for the display unit 11, and has low current consumption and is constantly energized from the power supply at a voltage lower than the power supply voltage of the main body (or this power supply or output register 1 is backed up by a backup power supply). (The output register 1 is energized by the backup power supply even when the liquid crystal display drive section is powered off). The main body can store, for example, film counter information in the output register 1 in advance, and read that information from the output register 1 when the power is turned on.

In this embodiment, the output register 1 as a memory means is not provided in the main body, which consumes a large amount of current, but is provided in the liquid crystal display drive section, which consumes a small amount of current, so that it is easy to protect it, and the load on the battery can be reduced. .

FIG. 2 shows another embodiment of the invention.

In this embodiment, in the above embodiment, output register 1
The shift register 2 for one-person operation is used as a storage means. Input shift 1 to register 2 have a carry flag section (9th bit) 12.

When the information of the first to ninth bits is input, the information of the first bit enters the carry flag section 12 and is sent to the main body via the buffer 11. The end of the information SI from the main unit remains in the input shift register 2, and the main unit uses the clock SCK as necessary.
The information can be read from the input shift register 2 by sending the information to the liquid crystal display driver. Even if the power is turned off and the internal memory is reset, the microcomputer in the main unit reads the contents of the input shift register 2 from the liquid crystal display driver first when the power is turned on again (so that the displayed contents do not change). Transfer the information to the LCD display again) and use that information for subsequent camera control.1 For example, if you leave the contents of the film counter in the input shift register 2, add 1 to that information at the release and drive the LCD display. Transfer to the department.

(Effects) As described above, according to the present invention, a storage means is provided in the liquid crystal display section, which consumes less current than the main body, and the camera information from the main body is stored so that the main body can read it. If it is not turned off, battery consumption can be suppressed, and if the power source is backed up, its capacity can be reduced. Furthermore, since there is no sudden drop in power supply voltage in the liquid crystal display drive section, there is no loss of information in the storage means.

[Brief explanation of drawings]

FIGS. 1 and 2 are block diagrams showing each embodiment of the present invention. 1...Output register, 2...Input shift register. Figure 1 2nd trouble

Claims (1)

[Claims] In a camera configured to constantly drive a liquid crystal display drive unit that displays various camera information at a voltage lower than the power supply voltage of the camera body, or to back up the power supply for the liquid crystal display drive unit, the liquid crystal display drive unit is provided with a A memory circuit for a camera comprising a storage means for storing camera information from the camera body and reading out the camera information in the camera body.