JPH0695609A - Multifunction displaying device - Google Patents

Abstract

PURPOSE:To eliminate the need of a clock circuit, to reduce the number of parts in a device and to reduce a space for arranging the clock circuit by providing a stepping function of a clock in a display control CPU. CONSTITUTION:The CPU 11 stops operation perfectly when ACC system power source 12 and +B system power source are turned off also. Further, in the state that the +B power source is supplied, when an ACC switch is turned on and the ACC system power source 12 is supplied to the CPU 11, a time display function, etc., are executed selectively by an operation part 15. At this time, while executing respective functions, clock processing for counting a time is executed at every fixed time. Further, when the ACC switch is turned off, and the +B system power source 13 is supplied to the CPU 11, and executions in respective functions are interrupted, a display means 14 becomes a non-display state, and the device is operated in a main routine stop mode. At this time, a clock timer interruption is generated at every 0.5SEC, and after the clock processing is executed, the device is set to the main routine stop mode.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-function display device,
In particular, the present invention relates to a multifunctional display device capable of displaying various types of images in addition to the time display.

[0002]

2. Description of the Related Art Motor vehicles are provided with various display devices for providing various information to the driver. However, if too many display devices are arranged, the driver is confused. Therefore, a so-called multi-display that selectively displays various information by one display means may be used.

FIG. 3 shows a block diagram of an example of a conventional multi-display. In the figure, reference numeral 1 denotes a CPU (central processing unit), to which drive power is supplied from an ACC power supply 2 which supplies power when an accessory (ACC) switch is turned on.

A temperature detection signal corresponding to the detected temperature is input to the CPU 1 from a temperature detection unit (not shown). Further, the clock circuit 3 supplies a signal according to the time. The clock circuit 3 obtains drive power from the + B system power source 4 which supplies power regardless of whether the accessory switch is on or off, and the clock circuit 3 is configured to count time even when the accessory switch is off.

The CPU 1 is also connected to the display unit 5 and supplies the display unit 5 with a display signal for displaying the temperature or a display signal for displaying the time. The display unit 5 displays the temperature or time according to the display signal from the CPU 1. At this time, the temperature display and the time display can be switched by the operation unit 6 connected to the CPU 1.

[0006]

However, in the conventional display device of this type, the accessory switch is turned off, and
When the CC system and the power supply 2 are no longer supplied, the time is counted by the clock circuit 3 provided separately from the display control CPU 1, and the clock circuit 3 is required in addition to the CPU 1, so the number of parts increases. In addition, there is a problem that it is difficult to downsize the device.

The present invention has been made in view of the above points, and an object of the present invention is to provide a multi-function display device with a timepiece function which can reduce the number of parts, and can be reduced in size and cost.

[0008]

SUMMARY OF THE INVENTION The present invention provides a display device having a display means capable of performing various displays including a time display, and a display control CPU for processing data to control the display of the display means. The display control CPU operates in a stop mode in which the data processing operation is stopped when the display means is not displayed, cancels the stop mode at regular intervals, and counts time.

[0009]

The CPU operates in the stop mode at the time of non-display, and releases the stop mode at regular time intervals by the CPU internal clock to perform time step processing. Therefore, in addition to the CPU for displaying the time, a separate clock circuit for counting the time is unnecessary.

[0010]

1 is a block diagram of an embodiment of the present invention. The present embodiment describes a vehicle-mounted multi-function timepiece system. In the figure, reference numeral 11 denotes a CPU (central processing unit) which is a calculation means. CPU11 has an accessory (ACC)
The voltage V _ACC is applied from the ACC power supply 12 which supplies the voltage when the switch is turned on, and the voltage V _B is applied from the + B power supply 13 which supplies the voltage when the accessory switch is turned off. Further, the CPU 11 is connected to the temperature detection unit and the vehicle speed detection unit, processes the data input from the temperature detection unit and the vehicle speed detection unit, and displays the display unit 14 and the alarm generation unit 1.
The control signal is supplied to 6.

The display means 14 comprises a liquid crystal panel or the like, and C
It is connected to the PU 11. The display means 14 displays various characters according to the display control signal from the CPU 11. The operation unit 15 includes a plurality of switches and is connected to the CPU 11. The operation unit 15 is a CPU 1 by switching a switch.
The display mode 1 can be switched.

The alarm generator 16 is composed of a buzzer or the like,
An alarm is generated according to the alarm control signal from the CPU 11.

When the accessory switch is turned on, the CPU 11
Performs a time display function, an alarm function, a temperature display function, and a vehicle speed warning function by switching modes.

The time display function controls the display of the time obtained by counting the clock signals generated internally. The alarm function sets an alarm time by operating the operation unit 15, and when the time reaches the alarm set time, the alarm generation unit 16 is drive-controlled to generate an alarm.

The temperature display function controls the display of the temperature according to the detected temperature signal input from the temperature detection unit connected to the outside. The vehicle speed warning function compares a detected vehicle speed signal input from an externally connected vehicle speed detection unit with a set vehicle speed obtained in advance by operating the operation unit 15, and when the detected vehicle speed exceeds the set vehicle speed, an alarm generation unit. Drive control 16
Raise an alarm.

The accessory switch is turned off, and the ACC
When the system power 12 is no longer supplied to the CPU 11, the CPU
Reference numeral 11 stops each of the above functions, and enters the main routine stop mode.

Next, the operation of the apparatus will be described with reference to FIG.

When the ACC power supply 12 and the + B power supply 13 are both turned off, the CPU 11 completely stops its operation (step S1).

Further, while the + B system power supply 13 is being supplied, the ACC switch is turned on, and the CPU 11 receives the ACC signal.
When the system power supply 12 is supplied, the time display function, the alarm function, the temperature display function, and the vehicle speed warning function are selectively executed by the operation of the operation unit 15 (steps S2 and S3). At this time, a clock process for counting the time is executed at regular time intervals during the execution of each function (step S4).

Further, the ACC switch is turned off, and CP
When only the + B system power supply 13 is supplied to U11, when the execution of each function is stopped, the display means 14 is hidden and operates in the main routine stop mode (step S).
5).

At this time, the clock timer interrupt is 0.5 SE.
The operation occurs every C, performs the clock processing (step S4), and then again enters the main routine stop mode (step S5).

As described above, in order not to stop the clock operation while the ACC switch is off, the main routine stop mode is canceled by the clock timer interrupt, the clock processing is performed, and then the operation is returned to the main routine stop mode again. By repeating the operation, the dark current can be reduced even when the CPU 11 performs the timepiece operation, and the timepiece circuit becomes unnecessary, so that the external circuits can be reduced.

[0023]

As described above, according to the present invention, the timepiece circuit is not required by providing the display control CPU with the stepping function of the timepiece, so that the number of parts of the device can be reduced and the timepiece circuit can be provided. It has features such as space saving of parts.

[Brief description of drawings]

FIG. 1 is a block diagram of an embodiment of the present invention.

FIG. 2 is an operation explanatory diagram of the embodiment of the present invention.

FIG. 3 is a block diagram of a conventional example.

[Explanation of symbols]

 11 CPU 12 ACC power supply 13 + B system power supply 14 Display means 15 Operation part 16 Alarm generation part

Claims (1)

[Claims] 1. A multi-function display device comprising a display means capable of performing various displays including a time display, and a display control CPU for processing data to control the display of the display means. Operates in a stop mode in which the data processing operation is stopped when the display means is not displayed, and the CPU internal clock cancels the stop mode at regular intervals to count the time. Function display device.