JP2001134155A - Device, system and method for detecting charging information and recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a charging information detecting device by which proper charging information is detected in accordance with printing in a picture printing device. SOLUTION: The charging information detecting device is for detecting charging information in accordance with printing in the printing device where printing is executed by dot unit in accordance with a printing data output clock and a binary printing data signal. The charging information detecting device is provided with a logical product arithmetic part 101 for obtaining the AND of the printing data output clock by the binary printing data signal and outputting an AND signal, a counter part 102 for counting the pulse number of the AND signal which is supplied from the arithmetic part 101 as a printing dot number and a processing part 106 for calculating charging information based on printing in the picture printing device in accordance with the printing dot number which is counted by the counter part.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a billing information detecting technique, and more particularly to a billing information detecting technique for detecting billing information in accordance with printing by an image printing apparatus.

[0002]

2. Description of the Related Art Image printing apparatuses (image forming apparatuses) include, for example, laser beam printers, copiers, and facsimile machines. The billing information detecting device detects billing information according to printing by the image printing device. The accounting information detecting device according to the related art obtains accounting information by counting the number of printed images (the number of copies) or the number of rotations of a photosensitive drum or a transfer drum of the image printing device.

[0003]

However, the billing information detecting device according to the prior art has a disadvantage in that, when a jam such as a paper jam occurs, an image that is not normally printed (printed out) is billed. there were.

In general, a higher fee is charged for color printing than for monochrome printing. However, some charging information detecting devices such as color laser beam printers and color copiers detect the charging information by counting the number of rotations of the transfer drum and the like.
Nevertheless, there is a case where a fee is charged for color printing. It is not preferable to detect the same billing information in color printing and monochrome printing.

More specifically, in print data transmitted from a personal computer, color printing and monochrome printing are mixed, as in the case where the first page is color printing and the second page is monochrome printing. A problem arises in some cases. When the charging information detecting device detects the information that the first page is color-printed, the information remains, and the second page may be incorrectly charged as color-printing.

An object of the present invention is to provide a charging information detecting apparatus, a charging information detecting system, a charging information detecting method, and a recording medium on which a computer program is recorded, which can detect appropriate charging information in accordance with printing by an image printing apparatus. It is to provide.

[0007]

According to one aspect of the present invention, accounting information corresponding to printing by an image printing apparatus that prints in dot units according to a print data output clock and a binary print data signal is detected. A billing information detecting device for calculating billing information based on printing of the image printing device in accordance with the print data output clock and the binary print data signal. Provided.

By calculating the billing information in accordance with the print data output clock and the binary print data signal, highly accurate and appropriate billing information can be detected.

According to another aspect of the present invention, accounting information for detecting accounting information corresponding to printing by an image printing apparatus that prints in dot units according to a print data output clock and a binary printing data signal. A detection device, which obtains a logical product of the print data output clock and the binary print data signal and outputs a logical product signal, and a logical product supplied from the logical product calculation unit A billing information detection device comprising: a counter unit that counts the number of pulses of a signal as the number of printing dots; and a processing unit that calculates billing information based on printing by the image printing device according to the number of printing dots counted by the counter unit. Is provided.

By calculating the billing information in accordance with the number of print dots, highly accurate and appropriate billing information can be detected in accordance with the amount of printed matter such as consumed toner. For example, if the number of print dots is counted in page units, in the case of a paper jam or the like, the number of print dots at that time is excluded from the billing target, so that the billing information of only the normally printed pages can be detected. it can.

According to still another aspect of the present invention, accounting information corresponding to printing by an image printing apparatus that performs color printing in dot units according to a print data output clock, a binary print data signal, and print color data. A logical product operation unit for obtaining a logical product of the print data output clock and the binary print data signal and outputting a logical product signal; and In response to the,
For each color, a counter unit that counts the number of pulses of the AND signal supplied from the AND operation unit as the number of print dots, and the image printing apparatus according to the number of print dots for each color counted by the counter unit And a processing unit for calculating the charging information for each color based on the printing of the charging information.

By counting the number of print dots for each color, appropriate accounting information can be detected not only for monochrome printing but also for color printing. Further, even if pages for monochrome printing and color printing are mixed, it is possible to detect appropriate billing information.

According to still another aspect of the present invention, there is provided an image printing apparatus for printing in dot units in accordance with a print data output clock and a binary print data signal, and an image printing apparatus comprising: a print data output clock; An AND operation unit that outputs an AND signal by taking an AND operation with a print data signal; a counter unit that counts the number of pulses of the AND signal supplied from the AND operation unit as the number of print dots; and the counter A billing information detection system including a processing unit for calculating billing information based on printing by the image printing apparatus in accordance with the number of print dots counted by the copy unit.

According to still another aspect of the present invention, there is provided an image printing apparatus for performing color printing in dot units in accordance with a print data output clock, a binary print data signal and print color data, and the print data output clock. A logical product operating unit that obtains a logical product of a clock and the binary print data signal and outputs a logical product signal; and a logical unit supplied from the logical product operation unit for each color according to the print color data. A counter unit that counts the number of pulses of the product signal as the number of print dots, and a processing unit that calculates billing information for each color based on printing by the image printing apparatus according to the number of print dots for each color counted by the counter unit. And a billing information detection device including the following.

According to still another aspect of the present invention, accounting for detecting accounting information corresponding to printing by an image printing apparatus that prints in dot units according to a print data output clock and a binary print data signal. An information detection method, comprising: (a)
Obtaining the logical product of the print data output clock and the binary print data signal and outputting a logical product signal; and (b) counting the number of pulses of the logical product signal as the number of print dots. (C) calculating billing information based on printing by the image printing apparatus in accordance with the counted number of print dots.

According to still another aspect of the present invention, accounting information corresponding to printing by an image printing apparatus that performs color printing in dot units according to a print data output clock, a binary print data signal, and print color data. (A) taking a logical product of the print data output clock and the binary print data signal, and outputting a logical product signal; and (b) outputting a logical product signal. Counting the number of pulses of the logical product signal as the number of print dots for each color according to print color data; and (c) printing the image printing apparatus according to the number of print dots for each color counted. Calculating the accounting information for each color based on the accounting information.

According to still another aspect of the present invention, there is provided a computer for detecting accounting information corresponding to printing of an image printing apparatus which prints in dot units according to a print data output clock and a binary print data signal. A recording medium on which a program is recorded, wherein (a) logically ANDing the print data output clock and the binary print data signal and outputting a logical product signal; and (b) the logical product signal. Counting the number of pulses as the number of print dots, and (c)
A computer-readable recording medium storing a program for causing a computer to execute a procedure for calculating accounting information based on printing by the image printing apparatus in accordance with the counted number of printed dots is provided.

According to still another aspect of the present invention, accounting information corresponding to printing of an image printing apparatus that performs color printing in dot units according to a print data output clock, a binary print data signal, and print color data. (A) logically ANDing the print data output clock and the binary print data signal, and outputting a logical product signal;
(B) a step of counting the number of pulses of the logical product signal as the number of print dots for each color according to the print color data; and (c) a step of counting the image according to the number of print dots for each color counted. A computer-readable recording medium that records a program for causing a computer to execute a procedure for calculating accounting information for each color based on printing by a printing apparatus is provided.

[0019]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a billing information detecting device 402 and an image printing device (image forming device) according to an embodiment of the present invention.
1 is a schematic diagram showing a billing information detection system having 401.

The accounting information detecting device 402 is connected to the image printing device 401. At this time, the charging information detecting device 402
May be provided outside the image printing apparatus 401 or may be built in the image printing apparatus 401. Image printing device 401
Is a laser beam printer, a copying machine, a facsimile, or the like.

Hereinafter, a case where the image printing apparatus 401 is a laser beam printer will be described as an example. The laser beam printer 401 has a drum-shaped photoconductor (photosensitive drum) rotatably supported. Around this photosensitive drum,
A primary charger, an exposure device, a developing device, a transfer charger, a cleaner, and the like are arranged in this order along the rotation direction.
Further, a fixing device is disposed downstream of the photosensitive drum in a transport direction of a transfer material (for example, paper) as a transfer destination of the toner image.

First, the primary charger uniformly charges the surface of the photosensitive drum to a predetermined negative voltage. After the charging, an electrostatic latent image is formed on the surface of the photosensitive drum by the exposure device. The exposure apparatus generates a laser beam by a laser oscillator, and guides the laser beam to a photosensitive drum via a lens, a polygon mirror, and the like. The surface of the photosensitive drum is irradiated with laser light as elliptical dots.

The main scanning is performed by moving the surface of the photosensitive drum in the generatrix direction by the rotation of the polygon mirror, and the dot is sub-scanned by moving in the circumferential direction by the rotation of the photosensitive drum. At this time, by performing on / off control of the laser light, the negative charge of the bright portion irradiated with the laser light is removed, and an electrostatic latent image is formed. That is, the electrostatic latent image is formed as a set of dots by main scanning and sub-scanning of laser light generated based on a print data signal (print data signal).

Next, the developing device attaches the charged toner contained in the developing container to the electrostatic latent image to develop the toner image. The amount of toner attached to the latent image corresponding to one dot of the laser light is substantially constant. Therefore, the amount of toner consumed for printing an image is proportional to the number of dots forming an electrostatic latent image.

The usage amount of the toner (printed matter) is proportional to the consumption amount of the toner. That is, assuming that the amount of toner consumed for printing one dot is c and the number of dots forming an electrostatic latent image is N, the total amount C of toner consumed by printing an image on a transfer material is C = C × N.

The toner image formed on the surface of the photosensitive drum is
The image is transferred to the surface of the transfer material conveyed by the sheet feeding device via a transfer charger. Thereafter, the toner image is fixed on the transferred transfer material by a fixing device, and is discharged outside the image printing apparatus. On the other hand, the cleaner removes transfer residual toner on the surface of the photosensitive drum and prepares for the next image printing.

The billing information detecting device 402 can detect accurate billing information from the amount of toner used. The principle is based on the fact that the amount of toner attached to the electrostatic latent image per dot formed by one dot of laser light is constant, as described above.

As shown in FIG. 1, when the image printing device 401 is a black-and-white laser beam printer, the billing information detecting device 402 sends five signals 2 from the image printing device 401.
Enter 01-205. On the other hand, when the image printing device 401 is a color laser beam printer, the billing information detection device 402 receives six signals 201 to 206 from the image printing device 401. Billing information detection device 402
Are the signals 201 to 205 or the signals 201 to 206 described above.
To detect billing information.

Next, the signals 201 to 206 will be described. FIG. 3 shows signal waveforms of the signals 201 and 202.
The signal 201 is a print data output clock (print data output clock) having a constant frequency, and is a timing clock when the laser beam printer 401 performs printing.

The signal 202 is a binary print data signal (print data signal), and is a signal for controlling on / off of the laser light. When the print data signal 202 is at a high level, toner is consumed, and when the print data signal 202 is at a low level, no toner is consumed.

More specifically, a laser beam printer 401
Prints in dot units according to the print data signal 202 in synchronization with the print data output clock 201. The high level of the signal 210 which is the logical product of the print data output clock 201 and the print data signal 202 corresponds to a print dot.

A signal 203 is a printing start signal, and a signal 2
04 is a print end signal, signal 205 is a normal / abnormal end signal, and signal 206 is a print color data signal.
Details of these signals will be described later.

FIG. 2 is a block diagram showing the configuration of the charging information detecting device 402 according to the first embodiment. The billing information detecting device 402 includes a monochrome laser beam printer 401.
Billing information is detected in accordance with signals 201 to 205 supplied from FIG.

The billing information detection device 402 has a logical product operation unit (AND gate) 101, a counter unit 102, a decoder unit 103, an adder 104, a memory 105, and a processing unit (processing unit) 106.

As shown in FIG. 3, the AND gate 101 calculates the logical product of the print data output clock 201 and the binary print data signal 202, and outputs a logical product signal 210. The counter unit 102 counts the number of pulses of the logical product signal 210 as the number of print dots, and outputs the counted number to the adder 104 via the data bus 107.

The memory 105 has an initial value of 0 and is a memory for storing the cumulative number of print dots. The decoder unit 103 has a memory 103a, and a print start signal 20.
3. A print end signal 204 for each page and a normal / abnormal print end signal 205 are input. Print start signal 203
Is supplied to the decoder unit 103, the decoder unit 103
Stores the value stored in the memory 105 into the internal memory 10
3a. Initially, 0 is stored in the internal memory 103a.
Is stored.

The decoder section 103 outputs the value in the internal memory 103a to the adder 104 via the data bus 108. The adder 104 adds the count value supplied from the counter unit 102 and the value supplied from the decoder unit 103, and outputs the added value to the decoder unit 103.

Upon receiving the print end signal 204 for each page, the decoder section 103 stores the added value supplied from the adder 104 in the internal memory 103a. When printing the first page, the number of dots printed on the first page is stored in the internal memory 103a.

Next, the decoder unit 103 checks whether the termination is a normal termination or an abnormal termination by a signal 205, and upon receiving the signal 205 indicating a normal termination, is stored in the internal memory 103a. The number of print dots is stored in the memory 105.

On the other hand, when the decoder unit 103 receives the signal 205 indicating an abnormal end due to a paper jam or the like, the number of print dots in the internal memory 103a is cleared, and the value in the memory 105 is newly stored in the internal memory 103a. Store. In other words, the number of print dots on pages that could not be printed normally is
I will not be charged.

The same operation is performed for printing the second and subsequent pages. In the internal memory 103a and the memory 105 of the decoder unit 103, the print dot numbers of only the normally printed pages are accumulated and stored.

The processing device 106 has a memory 106a for storing a toner amount c per dot. The accumulated printing dot number N stored in the internal memory 103a of the decoder unit 103 is input to the processing device 106. The processing unit 106 calculates the total amount of toner consumed (charging information) C by calculating the product of the toner amount c per dot and the accumulated print dot number N.

A display device (display unit) 109 may be provided so that the total amount C of the consumed toner is displayed on the display device 109. As described above, when printing is abnormally terminated due to a paper jam or the like, the number of dots on the page is not accumulated, so that the toner consumed when printing is not performed normally is excluded from the charging target, and Charging information can be detected. By counting the number of print dots, highly accurate billing information can be detected in accordance with the amount of toner (printed matter) consumed.

FIG. 4 is a block diagram showing the configuration of the charging information detecting device 402 according to the second embodiment. The billing information detecting device 402 is provided for the color laser beam printer 40.
1 (FIG. 1) is detected in accordance with signals 201 to 206 supplied from FIG. At this time, the charging information detecting device 402
Represents Y used in the color laser beam printer 401.
It is possible to detect billing information for each color of (yellow), M (magenta), C (cyan), and K (black).

The memory 305 has a memory area 305Y for storing the yellow accumulated dot count and a memory area 3 for storing the magenta accumulated dot count.
05M, a memory area 305C for storing the accumulated dot count of cyan, and a memory area 305K for storing the accumulated dot count of black.

When the print start signal 203 is supplied to the decoder 303, the numerical value of each color in the memory 305 is stored in the memory 303a in the decoder 303. The AND gate 301 calculates the logical product of the print data output clock 201 and the print data signal 202, and outputs a logical product signal 210.

The print color data 206 is transmitted to the decoder 303
And supplied to the counter 302. Counter part 3
02 counts the number of print dots for each color according to the logical product signal 210 and the print color data 206. At this time, the counter unit 302 can count the number of print dots of each color by clearing the counter value when the print color data 206 is switched to data of a different color.

The adder 304 calculates the number of print dots supplied from the counter 302 via the data bus 307,
The number of accumulated print dots supplied from the internal memory 303 a of the decoder unit 303 via the data bus 308 is added and output to the decoder unit 303.

The decoder unit 303 outputs a print end signal 204
Then, the output value of the adder 304 is stored in the internal memory 303a for each color. Upon receiving the normal end signal 205,
The numerical value for each color in the internal memory 303a is stored in the memory 305. Upon receiving the abnormal end signal 205, the internal memory 3
The numerical value in 03a is cleared, and the numerical value in the memory 305 is newly stored in the internal memory 303a.

The processor 306 has a memory 306a for storing the amount of toner per dot for each color, and stores the accumulated number of print dots for each color in the internal memory 303 of the decoder 303.
Input from a. Then, the processing device 306 can detect the toner consumption amount (charging information) for each color by calculating the product of the toner amount per dot and the cumulative number of printing dots for each color. By adding the billing information of each color, the total amount of consumed toner can be calculated.

If the display device (display unit) 309 is provided, billing information can be displayed on the display device 309. As described above, by detecting the charging information for each color according to the printing color data (printing color data), even if the pages of the color printing and the monochrome printing are mixed, the appropriate charging information of each printing is detected. can do.

The billing information detecting device may be applied to a bubble jet printer, an ink jet printer, and the like, in addition to the laser beam printer. That is, the printed matter attached to the transfer material is not limited to toner, but may be ink or the like.

Further, the present invention may be implemented by operating the charging information detecting device according to a program (software) stored in a computer (CPU or MPU) in the charging information detecting device or the image printing apparatus.

In this case, the program code itself of the software realizes the functions of the above-described embodiment, and the program code itself and means for supplying the program code to the computer, for example, storing the program code The recorded recording medium constitutes the present invention. As a recording medium for storing such a program code, for example, a floppy disk, a hard disk,
An optical disk, a magneto-optical disk, a CD-ROM, a magnetic tape, a nonvolatile memory card, a ROM, or the like can be used.

The configuration shown in the above embodiment is
Each of these is merely an example of an embodiment for carrying out the present invention, and the technical scope of the present invention should not be interpreted in a limited manner. That is, the present invention can be embodied in various forms without departing from the spirit or main features thereof.

[0056]

As described above, according to the present invention, billing information is calculated in accordance with the number of print dots, and thus, highly accurate and appropriate billing information can be calculated in accordance with the amount of attached printing substances such as toner. Can be detected. For example, if the number of print dots is counted in page units, in the case of a paper jam or the like, the number of print dots at that time is excluded from the billing target, so that the billing information of only the normally printed pages can be detected. it can.

Further, by counting the number of printing dots for each color, it is possible to detect appropriate accounting information not only for monochrome printing but also for color printing. Further, even if pages for monochrome printing and color printing are mixed, it is possible to detect appropriate billing information.

[Brief description of the drawings]

FIG. 1 is a schematic diagram illustrating a billing information detection system including a billing information detecting device and an image printing device according to an embodiment of the present invention.

FIG. 2 is a block diagram illustrating a configuration of a charging information detection device according to a first embodiment.

FIG. 3 is a timing chart for explaining the operation of the charging information detecting device.

FIG. 4 is a block diagram illustrating a configuration of a charging information detection device according to a second embodiment.

[Explanation of symbols]

101,301 AND gate (logical product operation unit) 102,302 counter unit 103,303 decoder unit 103a, 303a memory 104,304 adder 105,305 memory 106,306 processing unit 106a, 306a memory 107,108,307,308 Data bus 109, 309 Display device (display unit) 201 Print data output clock (Print data output clock) 202 Print data signal (Print data signal) 203 Print start signal 204 Print end signal 205 Normal / abnormal end signal 206 Print color Data (print color data) 210 AND signal 401 Laser beam printer (image printing device) 402 Billing information detecting device

Claims (20)

[Claims] 1. A billing information detecting device for detecting billing information according to printing of an image printing apparatus that prints in dot units according to a print data output clock and a binary print data signal. A billing information detection device having a processing unit for calculating billing information based on printing by an image printing device in accordance with a data output clock and the binary print data signal. 2. A billing information detecting device for detecting billing information according to printing of an image printing apparatus that prints in dot units according to a print data output clock and a binary print data signal. A logical product of a data output clock and the binary print data signal to output a logical product signal; and a number of pulses of the logical product signal supplied from the logical product calculation unit to a print dot number. A billing information detecting device, comprising: a counter unit that counts as a count; and a processing unit that calculates billing information based on printing by the image printing apparatus according to the number of print dots counted by the counter unit. 3. The printing apparatus according to claim 1, further comprising an adder for accumulating and adding the number of print dots counted by the counter unit for each print page, wherein the processing unit outputs billing information in accordance with the accumulated number of print dots. The charging information detecting device according to claim 2, which performs a calculation. 4. The decoder according to claim 3, further comprising a decoder that accumulates and adds only the pages that have been normally printed to the adder and that does not accumulate and add the pages that have abnormally finished printing to the adder. Billing information detection device. 5. When printing is completed normally,
A memory for storing the cumulatively added number of print dots; the decoder, when printing is abnormally terminated, clears the cumulatively added number of print dots and reduces the number of print dots stored in the memory. 5. The charging information detecting device according to claim 4, wherein the accumulative addition is restarted from the next page by using the charging information. 6. The charging information detecting device according to claim 5, wherein the processing unit calculates the charging information in accordance with a product of the amount of the printed matter per dot and the cumulatively added number of printing dots. 7. The charging information detecting device according to claim 6, further comprising a display unit for displaying said charging information. 8. A billing information detecting device for detecting billing information according to printing of an image printing device that performs color printing in dot units according to a print data output clock, a binary print data signal, and print color data. An AND operation unit that performs an AND operation on the print data output clock and the binary print data signal and outputs an AND signal, and for each color according to the print color data, A counter unit that counts the number of pulses of the AND signal supplied from the AND operation unit as the number of print dots; and a color based on printing by the image printing apparatus according to the number of print dots for each color counted by the counter unit. A billing information detection device comprising: a processing unit that calculates billing information for each of the billing information. 9. An adder that accumulates and adds the number of print dots for each color counted by the counter unit for each print page, and wherein the processing unit includes the accumulated number of print dots for each color. 9. The charging information detecting device according to claim 8, wherein the charging information is calculated according to the following. 10. The decoder according to claim 9, further comprising a decoder that accumulates and adds only the pages that have been normally printed to the adder and that does not accumulate and add to the adder for pages that have been abnormally printed. Billing information detection device. 11. A memory for storing the number of print dots for each color that has been accumulated and added when printing has been normally completed, and wherein the decoder has said memory that has accumulated and added when abnormally finished printing. 11. The charging information detecting device according to claim 10, wherein the number of print dots for each color is cleared, and the cumulative addition is restarted from the next page using the number of print dots for each color stored in the memory. 12. The processing unit calculates billing information for each color in accordance with the product of the amount of printed matter for each color per dot and the cumulatively added number of print dots for each color. 12. The charging information detection device according to item 11. 13. The charging information detecting device according to claim 12, wherein the processing unit calculates the total charging information by adding the charging information for each color. 14. The charging information detecting device according to claim 12, further comprising a display unit for displaying said charging information. 15. An image printing apparatus which prints in a dot unit according to a print data output clock and a binary print data signal, and a logical product of the print data output clock and the binary print data signal. An AND operation unit that outputs an AND signal, a counter unit that counts the number of pulses of the AND signal supplied from the AND operation unit as the number of print dots, and a number of print dots that the counter unit counts. And a processing unit for calculating the charging information based on the printing of the image printing apparatus. 16. An image printing apparatus for performing color printing in dot units according to a print data output clock, a binary print data signal, and print color data, and the print data output clock and the binary print data signal. A logical product operation unit for obtaining a logical product of the logical product signals and outputting a logical product signal, and the number of pulses of the logical product signal supplied from the logical product operation unit for each color according to the print color data, and A billing information detecting device including a counter unit that counts as a count, and a processing unit that calculates billing information for each color based on printing by the image printing device according to the number of print dots for each color counted by the counter unit. Billing information detection system. 17. A billing information detecting method for detecting billing information according to printing of an image printing apparatus that prints in dot units according to a print data output clock and a binary print data signal, comprising: A) taking the logical product of the print data output clock and the binary print data signal and outputting a logical product signal; and (b) counting the number of pulses of the logical product signal as the number of print dots. (C) calculating billing information based on printing by the image printing apparatus according to the counted number of print dots. 18. A charging information detecting method for detecting charging information corresponding to printing of an image printing apparatus that performs color printing in dot units according to a print data output clock, a binary print data signal, and print color data. (A) taking a logical product of the print data output clock and the binary print data signal and outputting a logical product signal; and (b) outputting a logical product signal for each color according to the print color data. Counting the number of pulses of the AND signal as the number of print dots; and (c) according to the number of print dots for each color counted.
Calculating accounting information for each color based on printing by the image printing apparatus. 19. A recording medium recording a computer program for detecting billing information according to printing of an image printing apparatus that prints in dot units according to a print data output clock and a binary print data signal. (A) taking the logical product of the print data output clock and the binary print data signal and outputting a logical product signal; and (b) counting the number of pulses of the logical product signal as the number of print dots. And (c) a procedure for calculating accounting information based on printing by the image printing apparatus in accordance with the counted number of printed dots. 20. A computer program for detecting billing information corresponding to printing of an image printing apparatus that performs color printing in dot units according to a print data output clock, a binary print data signal, and print color data. (A) taking a logical product of the print data output clock and the binary print data signal and outputting a logical product signal; and (b) responding to the print color data. Counting the number of pulses of the AND signal as the number of print dots for each color; and (c) according to the number of print dots for each color counted.
A computer-readable recording medium storing a program for causing a computer to execute a procedure for calculating accounting information for each color based on printing by the image printing apparatus.