JPH0524311A - Counting memory and compensation apparatus - Google Patents

Abstract

PURPOSE:To provide the above apparatus extremely reduced in the deviation of a count value even when there is the counting mistake due to the cutting-off of a power supply. CONSTITUTION:A count data memory means 2 making an address incremental at every desired operation to store count data, first and second count means 3a, 3b renewing count values when data is stored in the respective different predetermined addresses of the count data memory means 2, a judging means 5 judging whether the count values of the first and second count means 3a, 3b are correct when power supply is closed and a correction means 6 correcting the count values when the error of the count values is judged by the judging means 5 are provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a counting memory compensator.

[0002]

2. Description of the Related Art In a printer, for example, the total number of printed sheets is counted, and is used for replacement of consumables, maintenance time, and the like. Conventionally, an apparatus for performing such counting uses the EEPROM (El
The data is stored in a non-volatile storage means such as an electrically erasable and programmable ROM) and the data is rewritten each time printing of one recording sheet is started.

[0003]

In the conventional count storage device described above, if the power is turned off while the data in the storage means is being rewritten, the number data may not be stored correctly. For example, when writing the number-of-sheets data to a storage means of a plurality of bytes, the data is rewritten in 1-byte units, but if the power is turned off during the rewriting of the upper byte data, the value of the upper digit of the count value may change. Therefore, a large error occurs between the actual number of printed sheets and the count value, for example, 1,000 sheets, 10,000 sheets.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a counting memory compensating device in which even if there is a counting error due to power interruption or the like, the deviation of the counting value is extremely small.

[0005]

SUMMARY OF THE INVENTION According to the present invention, count data storage means for incrementing an address for each desired operation to store count data, and data are stored at different predetermined addresses of the count data storage means. A plurality of counting means for updating the count value when the power is turned on, a determination means for determining whether the count values of the plurality of counting means are correct when the power is turned on, and when the determination means determines an error in the count value. By providing a correction means for correcting the count value, the above problem is solved.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the apparatus according to the present invention is used in a printer will be described below with reference to the drawings.

In FIG. 1, reference numeral 1 is a detection means for detecting the start of printing on one recording sheet, and 2 is a count data storage means for storing check data for counting the number of printed sheets. "0" to "25"
5 ″ of 256 storage areas are used. Hereinafter, the storage area as the count data storage means 2 is referred to as area A. 3a
Is a first counting means for rewriting and storing the count value stored when the check data of the central address “127” of the count data storing means 2 is rewritten to a value incremented by one, 3b is a count data storage The second counting means stores the count value stored when the check data at the address "255" of the means 2 is rewritten into a value obtained by incrementing the count value by one, and each count means is 4 of the EEPROM. The storage area for bytes is used. Hereinafter, the storage area as the first counting means 3a is the area B, and the storage area as the second counting means 3b is the area C.
Say. Reference numeral 4 is a control means for rewriting the check data and each count value, and 5 is a judgment means for judging whether the count value of the first count means 3a and the count value of the second count means 3b are correct or incorrect when the power is turned on. Is a correction means for correcting the count value when the determination means 5 determines that the count value has an error.

FIG. 2 shows in detail the structure of the areas A, B and C. In this example, “55h” and “AAh” are used as the check data stored in the area A.

Next, according to the flow chart of FIG.
A normal counting operation of the number of printed sheets will be described.

First, when the detection means 1 detects that printing has started on the first recording sheet, the control means 4 controls "55h" and "55h" among the check data stored in the area A. A boundary address of "AAh" is searched. That is, the address is sequentially incremented from the address "0" of the area A, and the change in the check data at each address is detected. Then, the address where the check data has changed is used as the boundary address. For example, in FIG. 2, the check data “AAh” is stored in the addresses “0” to “4” of the area A, and the check data “55h” is stored in the addresses “5” to “255”. The boundary address is "5".

In this example, it is assumed that the check data "55h" is written in each address of the area A and the count value "0" is written in each of the areas B and C in the initial state. In this way, when the check data of all addresses in the area A is the same, the boundary address is set to "0". Then, the check data of this border address is changed to "A
Rewrite as Ah "(step A).

Next, when it is detected that printing has started on the second recording sheet, at this time, since the check data "AAh" is stored in the address "0" of the area A, the boundary address is It becomes "1" and the check data of this address is rewritten to "AAh". In this manner, the check data stored in the area A is sequentially rewritten each time printing is started on one recording sheet. Then, when printing is started on the 128th recording sheet and the check data at the boundary address “127” is rewritten, the count value “0” stored in the area B is incremented by 1 to “1”. Rewrite (step B).

Further, when the number of printed sheets is increased and printing is started on the 256th recording sheet and the check data at the boundary address "255" is rewritten, the count value "0" stored in the area C is continuously changed. It is incremented by 1 and rewritten to "1" (step C).

When the check data of the address "255" is rewritten in this way, the check data of all the addresses in the area A becomes "AAh", so that the next boundary address becomes "0" again.

As described above, the address of the area A is incremented by one each time printing is started on one recording sheet, and the check data of the address is rewritten, and the area is printed every 128th sheet. The count value of B is incremented by 1, and the count value of the area C is incremented by 1 every 256th sheet. Therefore, when the boundary address is smaller than "128", "(count value of area B) x 256 + (boundary address)" is used. When the boundary address is "128" or more, "(area B
The total number of printed sheets is calculated by "count value-1) x 256 + (boundary address)". Further, the total number of printed sheets is calculated by "(count value of area C) x 256 + (boundary address)" regardless of the value of the border address. Is calculated.

As described above, if either one of the count values of the areas B and C is a correct value, the correct total print number can be calculated. If both count values are incorrect, the correct total number of printed sheets cannot be calculated, but if multiple counting means are provided, when one count value is incorrect, it will be incorrect based on the other count value. The count value can be modified. That is, it is possible to always calculate the correct number of printed sheets by performing correctness / incorrectness determination and correction of the count value of each counting means at a desired timing.

Next, according to the flow chart of FIG.
The determination operation of the number of printed sheets and the correction operation will be described.
In this example, these operations are performed when the power is turned on.

First, when the power is turned on, the border address is detected by the control means 4 in the same manner as above, and it is determined whether or not the address is smaller than "128" (step D).

If the boundary address is smaller than "128", the judging means 5 judges whether the count value of the area B is equal to the count value of the area C. In normal operation, the two values should be equal, but when it is detected that they are not equal, the correction means 6 corrects the count value of the area C to the count value of the area B (step E).

On the other hand, when the boundary address is "128" or more, the count value of the area B is then determined by the determining means 5 to the area C.
It is determined whether or not the count value of +1. In normal operation, the count value of the area B should be the count value of the area C + 1, but when it is detected that this is not the case, the correction means 6 corrects the count value of the area B to the count value of the area C + 1. (Step F).

The correctness determination and correction operation will be specifically described. For example, when the boundary address is "127", printing is performed, and the count value of the area B is rewritten following the rewriting of the check data of the same address. It is assumed that the power supply is turned off during the process and the count value of the area B goes wrong. If the writing operation was completed normally, the count value of the area B would have been the count value of the area C + 1. in this case,
When the power is turned on again, the boundary address is detected first.
At this time, the boundary address is "128". Next, it is determined whether the boundary address is smaller than "128". Now, the boundary address is "128" or more, and in this case, it is next determined whether or not the count value of the region B is the count value of the region C + 1. Now, since the count value of the area B is not the count value of the area C + 1, the count value of the area B is corrected to the count value of the area C + 1 by the correction means 6 in step F.

In this way, the correctness / incorrectness determination and correction operation of the count values of the areas B and C are performed.

By the way, even if the check data in the area A is turned off before the check data is rewritten and the check data is not rewritten, the difference between the actual number of printed sheets and the count is only one.
It is a sheet.

In the above embodiment, the case where the apparatus according to the present invention is used for the printer has been described, but the present invention is not limited to this, and a predetermined operation such as an apparatus for counting the number of copies of a copying machine or other counting is performed. It is applicable if it repeats.

Further, in the above embodiment, the EEPROM is used as the count data storage means 2, the first count means 3a and the second count means 3b, but the present invention is not limited to this and, for example, a RAM having a backup power source may be used. Any non-volatile storage means capable of rewriting data may be used.

In the above embodiment, the addresses of the count data storage means 2 are "0" to "255", but the number of addresses may be set arbitrarily.

In the above embodiment, the number of counting means is two, but this number may be set arbitrarily.

[0028]

According to the present invention, for example, even when the power is turned off during the counting operation, it is possible to count the actual predetermined number of times of operation of various devices extremely accurately.

[Brief description of drawings]

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

FIG. 2 is an explanatory diagram showing a configuration of a main part of FIG.

FIG. 3 is a flowchart for explaining a counting operation.

FIG. 4 is a flowchart for explaining correctness / incorrectness determination and correction operation of a count value.

[Explanation of Codes] 2 Counting Data Storage Means 3a First Counting Means 3b Second Counting Means 5 Judging Means 6 Modifying Means

Claims (1)

Claim: What is claimed is: 1. Counting data storage means for incrementing an address for each desired operation to store count data, and data is stored at different predetermined addresses of the count data storage means. A plurality of counting means for updating the count value, a determining means for determining whether the count values of the plurality of counting means are correct when the power is turned on, and a determination means for determining an error in the count value,
A counting memory compensating apparatus comprising: a correcting unit that corrects the count value.