CN102043722A - Automobile total mileage storage method - Google Patents

Abstract

The invention discloses an automobile total mileage storage method. The method comprises the following steps of: detecting whether a memory fails or not after a program runs to a data storage function, namely reading the previous successfully stored data address if an total mileage number changes in the state that the memory does not fail and does not have storage errors during program running; if the data is stored for the first time, storing the data in a memory origin address; updating a data address, resetting the number of errors and writing the current total mileage; and if unsuccessful writing occurs in the writing process, returning to the data storage function and entering a new storage flow. The method is simple, has high efficiency and is reliable and practicable; and by the method, mileage data loss is avoided, actual mileage data information is provided for a user, and the problem that the total mileage of the entire automobile cannot be accurately recorded when a storage error occurs in a data storage area is solved.

Description

A kind of storage means of automobile total kilometrage

Technical field

The present invention relates to storage means, be specifically related to a kind of storage means of automobile total kilometrage.

Background technology

Running car total kilometrage number is automobile life cycle the inside one of parameter the most always.It represents corresponding vehicle total distance travelled number at present, and value assessment has very important reference role to automobile.Simultaneously, it provides about the Vehicle-Miles of Travel important information for the driver, for vehicle maintenance provides the most direct foundation.Generally speaking, the speedometer for automobile number is by storer vehicle driving mileage to be carried out record, and when distance travelled changes greater than 1Km, it will carry out data writing operation to internal storage, and new mileage number is write the memory block.After power down appears in car, will read the numerical value of current mileage from the memory block, and it will be presented on the corresponding display module.If the data of storing in the memory block go wrong, power down and recover the car load power supply after, on the display module data presented will occur with actual conditions be not inconsistent problem.This problem will be brought very serious consequence, and the client produces great complaint.

At present, the method for speedometer for automobile number storage is generally the fixed address memory module.When distance travelled changed greater than 1Km, it write data to storage address, write second address once more after successfully writing first address, then, write the 3rd address again.If certain address write error wherein, its will be once more at this point the location write data, if write unsuccessfully once more, will write once more, and by that analogy.If after certain address existing problem, will consistent write data, but write unsuccessful always at this.After the vehicle mileage changes, also in place, existing problems address write data, thereby cause the failure of partial data mileage information record, after powering on once more, mileage information is lost.

Summary of the invention

The storage means that the purpose of this invention is to provide a kind of automobile total kilometrage, when it can a certain unit goes wrong in storage area, storer still can effectively be stored mileage number normally, prevent and show on actual travel mileage number and the display screen that mileage number does not conform to, and the saltus step phenomenon occurs.

The storage means of a kind of automobile total kilometrage of the present invention, its step is as follows:

When program run behind the data storage function, detection of stored device fault whether at first:

If after the storage failure flag set, will no longer carry out the data storage action, and show the total kilometrage error message in demonstration place, the current storage errors that occur of expression storer;

If storer does not have fault, then judge whether it is preceding once storage failure; If the address that storage is failed is then skipped in preceding once storage failure, memory address is upgraded, then, write once more; If write success, updated stored address once more then, the zero clearing of storage errors number of times is up to writing number of success greater than till requiring success to write indegree;

If occur writing unsuccessful phenomenon in ablation process, then errors number adds 1, and whether misjudgment number of times number of times reaches permission errors number maximal value; If do not reach, then turn back to the data storage function; If greater than errors number maximal value Er_limit, judge that then there is fault in storer, the storage failure sign puts one;

If in program operation process, there are not fault, storage not to have under the error condition at storer, if the total kilometrage numeral changes, once successfully deposit data address in before then at first reading; If storage then is address, storer top for the first time; Then, upgrade data address, the zero clearing errors number writes current total kilometrage number again; If in ablation process, unsuccessful situation appears writing, and then the return data storage function enters Stored Procedure again again.

The characteristics of this method are: storage errors appear in a certain storage unit in storer, in the time of can't successfully writing data, adopt the method can not influence the storage of these data, can skip this damaged memory unit and carry out the total kilometrage storage; If a large amount of storage unit can't successfully write data the time, can show the current storage existing problems to the user, inform the existence of customer problem, thereby prevented that effectively jumping phenomenon from appearring in the total kilometrage data.

This method is simple, efficient is higher, and it is reliably feasible, to stop the phenomenon that mileage is lost after the use, provide a real mileage information to the user, and, when its certain part existing problems of storage, adopt the method to appoint and to use this storer, till storer damages fully.

Description of drawings

Fig. 1 is a logical flow chart of the present invention.

Embodiment

Below in conjunction with Figure of description the present invention is further described:

Referring to Fig. 1, the storage means of a kind of automobile total kilometrage of the present invention, its step is as follows:

After " data storage function " arrived in program run, at first be to have judged whether " storage failure "-1;

If there is fault in storer, then display module directly " shows the mileage mistake "-2, and no longer carries out data storage function;

If there is not fault in storer, judge then whether last stored " storage errors "-3 take place;

If storage errors do not take place, " the mileage variation "-5 of judging then whether the current data total kilometrage takes place;

Do not change if mileage takes place, then do not carry out data storage;

If the mileage variation has taken place, then at first " once successfully store data address before reading ", at this point carry out " the errors number zero clearing is upgraded in the address "-6 on the basis of location, represent the current mistake that do not have; After scheduler, with " current mileage writes the address ";

If " write success ", then " number of success+1 errors number zero clearing " promptly successfully increases once, and judges whether write number of success＞Suc_limit number;

If do not reach stipulated number, then scheduler is again carried out data write operation once more, up to successfully write indegree up to specification till;

If in ablation process, unsuccessful phenomenon appears writing, at first " misregistration address ", " errors number+1 " then, gets back to the program entry place, handles by storage errors judgement flow process again; Storage errors occur, then the address is upgraded, skip the address that storage errors occur; Behind the new address, the mileage information that misregistration occurs is write new address once more;

If write success, then successfully writing indegree increases, and judges whether to satisfy the number of times that regulation requires again; If satisfy, then turn back to the data storage function entrance;

If do not satisfy Suc_limit the number that regulation requires, then upgrade data address once more, write once more, up to satisfying Suc_limit the number that regulation requires;

If " storage errors " have taken place, then to storage " address renewal "-4;

When " mileage that storage errors will occur writes the address ", at first be to judge whether " writing success ":

If write unsuccessfully, " misregistration address "-7 then, and when upgrading in the later stage address, skip this fault address to " errors number+1 "-9, promptly adds " 1 " action, illustrate to write frequency of failure increase by 1 time;

Judge whether " errors number＞Er_limit "-11 that write:

If errors number＞Er_limit number then is judged as " storage failure "-12, no longer carry out the mileage storage operation, corresponding sign in the software is put an operation;

If errors number does not reach number Er_limit time, then attempt writing data once more;

When the mileage that storage errors occur when storage writes the address, if " writing success ", then " address renewal " will write down " number of success+1 errors number zero clearing "-8, illustrate successfully to write data;

Judge whether " number of success＞Suc_limit "-10:

If number of success＞Suc_limit number, this represents that these data have finished data storage;

If number of success does not reach number Suc_limit time, " address renewal " writes once more then once more, reaches the data backup function.

Claims (1)

1. the storage means of an automobile total kilometrage, its step is as follows:

When program run behind the data storage function, detection of stored device fault whether at first:

If after the storage failure flag set, will no longer carry out the data storage action, and show the total kilometrage error message in demonstration place, the current storage errors that occur of expression storer;

If storer does not have fault, then judge whether it is preceding once storage failure; If the address that storage is failed is then skipped in preceding once storage failure, memory address is upgraded, then, write once more; If write success, updated stored address once more then, the zero clearing of storage errors number of times is up to writing number of success greater than till requiring success to write indegree Suc_limit;

If occur writing unsuccessful phenomenon in ablation process, then errors number adds 1, and whether misjudgment number of times number of times reaches permission errors number maximal value Er_limit; If do not reach, then turn back to the data storage function; If greater than errors number maximal value Er_limit, judge that then there is fault in storer, the storage failure sign puts one;

If in program operation process, there are not fault, storage not to have under the error condition at storer, if the total kilometrage numeral changes, once successfully deposit data address in before then at first reading; If storage then is address, storer top for the first time; Then, upgrade data address, the zero clearing errors number writes current total kilometrage number again; If in ablation process, unsuccessful situation appears writing, and then the return data storage function enters Stored Procedure again again.

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