JPH02201219A - Electronic type odometer - Google Patents

Abstract

PURPOSE:To simplify the preparation of a program by determining an address of an EEPROM for storing an integration data with an encoder. CONSTITUTION:A normal reloading into an EEPROM 1 is performed by an updating at a specified address and when a tripmeter is reset, an output of an encoder changes and an address of the EEPROM 1 for updating a writing is shifted accordingly. Therefore, as an address of the newest data of the EEPROM 1 stored mechanically with the encoder 5, a data stored at an address of the EEPROM 1 is read out corresponding to an output of the encoder 5 at a resumption. This dispenses with a program for starting at the resumption while enabling uniform use of a memory of the EEPROM 1 by reloading.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application) The present invention relates to an electronic odometer mounted on a vehicle that displays the cumulative mileage.

(Prior art) An electronic odometer that indicates the cumulative travel distance of a vehicle consists of: - a counter that integrates signals from a travel distance sensor that converts the rotational speed of a wheel shaft, etc., into a signal for boat fishing, and an integrated value; The vehicle is comprised of a display section that displays the cumulative travel distance based on the following. An on-vehicle battery is used as a drive source for each of the above-mentioned parts, but if the power supply to the counting part is stopped when the battery is replaced, the mileage data will be lost. As a countermeasure against this problem, storing cumulative mileage data in a non-volatile memory is widely practiced.

In particular, instruments that use EEPROM as a non-volatile memory are often used, but as the number of rewrites and updates of EEPROM increases, its reliability decreases. It has been rewritten and updated to make it available for use.

(Problem to be Solved by the Invention) In order to prevent only a specific address from being used in the EEPROM memory, the address is migrated every predetermined mileage, and the integrated data is stored in various formats at the migrated address. Although a method of rewriting (rewriting all travel cumulative data, rewriting the upper digits and lower digits separately, and rewriting only the upper digits) is adopted, when the display is resumed (the beginning of the cumulative data from the EEPROM) (reading) requires a program to read the address of the latest data, and creating that program itself is complicated.

(Means for Solving the Problems) In order to solve the above-mentioned problems, the present invention mechanically stores the read address at the time of restarting the EEPROM, eliminates the need for a restart program, and uniformly stores the memory of the EEPROM. It was rewritten and used.

That is, the electronic odometer according to the present invention has an encoder operated by a trip meter reset lever in an electronic odometer in which an EEPROMftIIa is installed as an integration value memory in a counting section that integrates values corresponding to signals from a mileage sensor. The integrated value storage address of the EEPROM is determined by the output of the encoder. It is characterized by this.

(Function) Rewriting to the EEI'ROM during normal times is performed by updating at a predetermined address, and when the trip meter is reset, the encoder output changes, and accordingly, the address of the EEPROM to be updated is changed. Make the transition. Therefore, the address of the latest data in EEr'ROM is mechanically memorized by the encoder, so when restarting, the EEP corresponding to the encoder output
The data stored in the ROM address is read out.

(Example) Next, an embodiment of the present invention shown in the drawings will be described.

The electronic odometer according to the embodiment of the present invention consists of a counting section and a display section, and the counting section includes an EEPROMI, a preset counter 2. Counter 3, EEPROM controller 4.
Consists of an encoder 5, and a display unit includes a decoder 6 and an LCD.
Consists of 7. EEPROMI is a non-volatile memory that stores cumulative mileage data, and the preset counter 2 receives mileage data (counted value) from the counter 3 and sequentially integrates the mileage data recorded in the previous preset counter 2. In addition to outputting the integrated value to the display unit, E
Send memory data (integrated data) to EPROMI. Further, the counter 3 receives input from the mileage sensor, counts a predetermined mileage, and sends a signal to the preset counter for each predetermined counting unit, and the EEPROM controller 4 controls the setting of the memory address of the EEPROMI and the memory The encoder 5 is used to instruct the timing, and the output of the encoder 5 can be varied by directly changing the position mechanically or electrically by operating the reset lever for the trip meter. It emits an instruction signal to the EEPROM controller 4. The decoder 6 in the display section receives the output of the preset counter 2 and displays! ! (LCD) 7 is driven, and the display (LCD) 7 displays the cumulative mileage of the vehicle.

Each component of the counting section and display section receives driving power from the on-vehicle power unit, and is configured to transmit signals when the ignition switch is turned on and off, as well as input OFF No. 41 from the battery, to the counting section. Become.

Next, the operation of the above embodiment will be explained.

During normal driving, when a sensor input (pulse signal) is received, the counter 3 counts until the predetermined travel distance tS<display minimum unit road gl), and when the predetermined travel distance is reached, a unit signal is sent to the preset counter 2, and the preset counter When the unit signal 2 is received, it is added to the previous counter value (cumulative travel distance value) to obtain a new integrated value, and this is displayed on a display (LCD) 7 via a decoder 6. When you finish driving the vehicle and turn off the ignition switch, the E
In response to instructions from the EPROM controller 4, the integrated value of the preset counter 2 is stored in the specified address of the EEPROMI. The EEPROM controller 4 instructs this instruction address in response to an instruction signal determined by the output of the encoder 5. EEPRO is determined by the output of encoder 5 at the start of driving, that is, when the ignition switch is turned on.
The mileage data stored in the specified address of M1 is transmitted to the preset counter 2, and the data is displayed on the display section 7, and integration from the data is started. When the trip meter reset lever is operated, the output of the encoder 5 is changed to switch the instruction address, and the latest mileage data, that is, the accumulated data of the preset counter, is stored in the instruction address. Furthermore, for data preservation, the accumulated data of the preset counter is stored in the designated address even when the battery is removed.

Therefore, the accumulated data of preset counter 2 is EEP as appropriate.
Since it will be stored at the specified address of ROMI and the address of the specified address is mechanically memorized by the encoder 5, it will be stored in the EEPROM when restarting.
There is no need to specifically search for the storage address of the latest data stored in l. Furthermore, each time the reset lever for the trip meter is operated, the instruction address, that is, the address where data is updated, changes, so in the long run, E
All addresses in the EPROM will be rewritten on average.

It should be noted that the present invention is not limited to the above-mentioned embodiments, and in its configuration, an LED other than an LCD may be used in the display section.
Furthermore, other notification means may be used without providing the display unit itself. In addition, the CPU is used for integration processing, EEPROM control, etc.
You may also use Further, the operation of each component is not particularly limited to the above-described embodiments, and as long as the present invention includes at least an encoder and the data storage address of the EEPROM is determined by the encoder, other configurations and operation programs can be changed as appropriate. It's a good thing.

(Effects of the Invention) As described above, the present invention provides an EEP in the nonvolatile memory of the counting section.
An electronic odometer using ROM is equipped with an encoder that is operated by a trip meter reset lever.
EEPR that stores integrated data by the encoder
This method determines the OM address, and the address that stores the latest data among multiple addresses must be mechanically memorized, so the start data when restarting does not have to be configured in a complicated sequence. In addition, in the long run, multiple addresses will be uniformly rewritten and updated, and the problem of limiting the number of writes can be solved.

[Brief explanation of the drawing]

The figure is a simple block diagram showing an embodiment of the invention. 1 is EEPROM 2 is preset counter 3 is the counter 4 is EEPROM controller 5 is encoder 6 is a decoder 7 is LCD

Claims (1)

[Claims] (1) In an electronic odometer that is equipped with an EEPROM as an accumulation value memory in the counting section that integrates the values corresponding to the signals from the mileage sensor, an encoder that is operated by the trip meter reset lever is provided, and the output of the encoder is provided. An electronic odometer characterized in that an integrated value storage address of the EEPR OM is determined by: