JP2004074711A - Image forming apparatus, communication control method therefor, storage medium, and program product - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To efficiently perform normal processing and communication by using a central processing unit (CPU) of an engine control part, without providing another CPU. <P>SOLUTION: The reception of printing instructions from a printer controller is monitored (S610), and a communication clock speed between a memory communication control part 210 and the engine control part 202 is expressed as CLK1 when the printing instructions are received (S611). The CLK1 is a lower communication speed than CLK0 which is predetermined inside the CPU. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an image forming apparatus, a communication control method therefor, a storage medium, and a program product, and more particularly, to an image forming apparatus having a non-volatile memory mounted on a detachable unit having an image carrier, a communication control method therefor, and storage. The present invention relates to a medium and program products.
[0002]
[Prior art]
Conventionally, this type of electrophotographic printer has a configuration as shown in FIG. Here, 101 is a photosensitive drum for forming an electrostatic latent image, 102 is a charging roller for uniformly charging the photosensitive drum 101, and 103 is a visible electrostatic latent image on the photosensitive drum 101. A developing unit for forming an image; 104, a toner container serving as a developer; 105, a cleaner for cleaning untransferred toner; 106, a memory unit having a non-volatile memory for storing data such as the number of prints; Is a process unit (cartridge) constituted by 101 to 106, and is detachable from the main body. The process unit is not limited to a process cartridge in which the photosensitive drum 101, the charging roller 102, the developing device 103, the toner container 104, the cleaner 105, and the memory unit 106 are integrated as shown in FIG. And a memory unit 106, and a drum cartridge in which the photosensitive drum 101 and the memory unit 106 are integrated.
[0003]
Reference numeral 108 denotes a laser serving as a light source for forming an electrostatic latent image on the photosensitive drum 101; 109, a polygon mirror for scanning a laser beam from the laser 108 on the photosensitive drum 101; 110, a return mirror; Denotes an optical unit composed of 108 to 110; 112, a paper cassette for stacking paper as a transfer material; 113, a paper presence / absence sensor for detecting presence / absence of paper in the paper cassette 112; A pickup roller 115 for feeding the paper stacked in the paper cassette 112 to the transport path, a paper feed roller 115a which is located downstream of the pickup roller 114 and has a function of feeding the paper onto the transport path and a function of preventing double feed; A pair of retard rollers 115b, 116 is a conveying roller, and 117 is a roller for correcting skew of the sheet. A strike shutter 118 is a TOP sensor for detecting the leading edge of the sheet and timing transfer of the image to a writing position sheet. 119 is a transfer roller for transferring the toner on the photosensitive drum 101 to the sheet. 120 is a transfer roller. A fixing roller for fixing the transferred toner to the paper, a fixing paper discharge sensor 121 for detecting whether the paper is normally output from the fixing roller 120, and 122 and 123 for a paper discharge until the paper is discharged outside the machine. It is a discharge roller for carrying.
[0004]
FIG. 2 shows functional blocks for controlling the configuration.
Reference numeral 201 denotes a function for developing image data from the host computer into dot information for turning on the laser, and a request for printing or printing to a printer engine which is an image forming unit for recording an image based on the developed dot information. This is a printer controller having a function of instructing the state of the engine at the time of performing the operation and checking the state of the engine, and exchanges information with the host computer via an interface (not shown) or the like. Reference numeral 202 denotes an engine control unit that controls each unit of a printer engine, which will be described later, in accordance with instructions from the printer controller 201; 203, a paper conveyance control unit that executes a driving system for conveying paper based on instructions from the engine control unit 202; And an optical system control unit that executes control of laser and the like based on instructions from the engine control unit 202; 205, a high-voltage control unit that executes various high-voltage outputs of charging, development, and transfer based on the instructions from the engine control unit 202; A fixing unit temperature control unit for controlling the temperature of the toner container to a predetermined temperature based on an instruction from the engine control unit 202; a monitoring unit 207 for monitoring the remaining amount of toner inside the cartridge; A toner-out detecting unit for notifying the toner-out to 202, and a process cartridge 202 is mounted in 208. Cartridge detector unit for detecting whether the, 209 denotes a sensor input unit for detecting an input signal from the paper presence sensor, such as TOP sensor. A memory communication control unit 210 executes communication with the memory unit 106 mounted on the process cartridge 107 based on an instruction from the engine control unit 202.
[0005]
FIG. 3 shows an electrical connection configuration between the engine control unit 202 and the memory communication control unit 210 and the memory unit 106 mounted on the process cartridge 107 in FIG. The engine control unit 202 has a CPU 301 mounted thereon, and the memory communication control unit 210 has a serial signal interface unit 302. The serial signal interface unit 302 receives a memory drive signal (MEMON) 303, a data output signal (CMD) 304, and a clock request signal (CLKSTART) 305, and supplies a data input signal (STS) 306 and a clock signal (CLK) to be supplied to the CPU 301. 307 is output.
[0006]
The serial signal interface unit 302 converts the address of the memory, the designation of read / write, and the data to be stored in the memory into the data output signal 304 and the data read from the memory and the processing result of the command into the data input signal 306 in time series. Let
[0007]
The memory communication control unit 210 accesses the memory unit 106 in the memory communication control unit 210 for data writing / reading according to the instruction received by the serial communication interface unit 302. As the memory, for example, an EEPROM can be considered. An access procedure to the EEPROM will be described. The memory communication control unit applies a power supply voltage to the EEPROM. Then, the chip select signal (CS) of the EEPROM is turned on. In this state, the command is issued to the data input terminal (DI) in synchronization with the clock signal. For example, when a code indicating a read command and an address to start reading are input to DI, the data of an address specified by the data output terminal (DO) at the beginning is synchronized with the subsequently supplied clock signal. Is output.
[0008]
[Problems to be solved by the invention]
However, in the conventional configuration, the clock of the serial communication between the CPU with the engine control unit and the memory communication control unit is output by the memory communication control unit. There is a problem that the resources are occupied. In addition, since the number of clocks for performing a series of communication in the communication protocol between the engine control unit and the memory communication control unit greatly exceeds the conventional serial communication standard of 8 bits to 16 bits for both the transmission command and the reception status, the CPU is mounted. The serial communication function cannot be used, and the port must be directly accessed by the CPU, so that there is a problem that other processing cannot be performed during communication. Conventionally, these problems have been dealt with by a method of providing another CPU mainly for communication with the memory communication control unit between the CPU equipped with the engine control unit and the memory communication control unit.
[0009]
An object of the present invention is to provide an image forming apparatus, a communication control method thereof, a storage medium, and a program product which can solve the above-mentioned problem with a configuration in which a memory communication system having an inexpensive configuration is mounted.
[0010]
[Means for Solving the Problems]
In order to achieve the above object, according to one aspect of the present invention, there is provided an engine control having mounting means for detachably mounting a cartridge having at least storage means for storing print information, and control means for controlling an engine unit. An image forming apparatus comprising: a memory communication control unit that controls communication between a unit and the storage unit; wherein the control unit includes an engine state determination unit that determines a state of the engine unit; and an engine state determination unit. And a serial signal for changing a clock rate of the clock signal from the engine control unit to the memory communication control unit according to the determined execution state. Output means for operating the serial signal output means in accordance with the determined execution state. An image forming apparatus having the configuration for controlling the communication between the engine control unit in accordance with the state of the emission portion and the storage means is performed.
[0011]
Here, it is also preferable that when the engine state determining means detects that a printing operation is being performed, the serial signal output means stops sending the clock signal.
[0012]
Here, it is also preferable that, when the engine state determining means detects that a printing operation is being performed, the serial signal output means sends the clock signal at a lower rate than the clock rate of the clock signal during standby.
[0013]
Here, it is preferable that the serial signal output unit further changes a data output signal from the memory communication control unit to the engine control unit according to the determined execution state.
[0014]
According to another aspect of the present invention, there is provided an engine control unit having a mounting unit for detachably mounting a cartridge having a storage unit for storing at least print information, an engine control unit having a control unit for controlling an engine unit, and the storage unit. A communication control method for an image forming apparatus, comprising: a memory communication control unit that controls communication between the engine unit; an engine state determination step of determining a state of the engine unit by the control unit; and a determination result in the engine state determination step. Determining the execution state of the communication, and changing the clock rate of the clock signal from the engine control unit to the memory communication control unit in accordance with the determined execution state. Operating the serial signal output means in accordance with the executed state, and according to the state of the engine unit. It was was performed communication control method of the image forming apparatus according to execute a communication control step of controlling the communication between said storage means and said engine control unit.
[0015]
Here, when it is detected that the printing operation is being performed in the engine state determination step, it is preferable that the transmission of the clock signal is stopped in the communication control step.
[0016]
Here, when it is detected that the printing operation is being performed in the engine state determination step, it is preferable that the communication control step transmits the clock signal having a lower rate than the clock rate of the clock signal in a standby state.
[0017]
Here, it is preferable that the communication control step further includes changing a data output signal from the memory communication control unit to the engine control unit according to the determined execution state.
[0018]
According to still another aspect of the present invention, at least mounting means for detachably mounting a cartridge mounted with storage means for storing print information, an engine control unit having control means for controlling an engine unit, and the storage means A storage medium storing a program for a communication control method for an image forming apparatus, comprising: a memory communication control unit for controlling communication between the plurality of image forming apparatuses, wherein the program determines the state of the engine unit by the control unit. And a determining step of determining an execution state of the communication in accordance with a determination result in the engine state determining step; and the clock signal from the engine control unit to the memory communication control unit in accordance with the determined execution state. The serial rate is changed according to the determined execution state by changing the clock rate of the serial. By operating the signal output means it is implemented in the form of a storage medium for executing a communication control step of controlling the communication between the engine control unit and the storage means in accordance with the state of the engine unit.
[0019]
Here, when it is detected that the printing operation is being performed in the engine state determination step, it is preferable that the transmission of the clock signal is stopped in the communication control step.
[0020]
Here, when it is detected that the printing operation is being performed in the engine state determination step, it is preferable that the communication control step transmits the clock signal having a lower rate than the clock rate of the clock signal in a standby state.
[0021]
Here, it is preferable that the communication control step further includes changing a data output signal from the memory communication control unit to the engine control unit according to the determined execution state.
[0022]
According to still another aspect of the present invention, at least mounting means for detachably mounting a cartridge mounted with storage means for storing print information, an engine control unit having control means for controlling an engine unit, and the storage means A communication control method for an image forming apparatus, comprising: a memory communication control unit that controls communication between the first and second communication units; and an engine state determination step of determining a state of the engine unit by the control unit; A determination step of determining the execution state of the communication in accordance with the result of the determination, and changing a clock rate of the clock signal from the engine control unit to the memory communication control unit in accordance with the determined execution state. By operating the serial signal output means in accordance with the determined execution state, The form of the program for executing a communication control step of controlling the communication between the engine control unit in accordance with the state of the parts and said storage means is performed.
[0023]
Here, when it is detected that the printing operation is being performed in the engine state determination step, it is preferable that the transmission of the clock signal is stopped in the communication control step.
[0024]
Here, when it is detected that the printing operation is being performed in the engine state determination step, it is preferable that the communication control step transmits the clock signal having a lower rate than the clock rate of the clock signal in a standby state.
[0025]
Here, it is preferable that the communication control step further includes changing a data output signal from the memory communication control unit to the engine control unit according to the determined execution state.
[0026]
BEST MODE FOR CARRYING OUT THE INVENTION
(Embodiment 1)
The structure and operation of the printer according to the present invention will be described with reference to FIG.
FIG. 1 is a schematic diagram of a printer. In FIG. 1, reference numeral 101 denotes a photosensitive drum serving as an electrostatic latent image carrier, and a charging roller 102 for uniformly charging the surface of the photosensitive drum 101 is provided above the photosensitive drum 101. It is in contact with the surface.
[0027]
The optical unit 111 irradiates a light beam to the charged surface on the downstream side in the rotation direction of the photosensitive drum 101 from the contact position of the charging roller 102.
[0028]
The optical unit 111 includes a laser 108 that emits a light beam, a polygon mirror 109 that scans the light beam on the surface, and a folding mirror 110, and irradiates the light beam based on image data to emit the light beam. An electrostatic latent image is formed on the surface.
[0029]
The electrostatic latent image is developed as a toner image by a developing device 103 disposed so as to be in contact with the photosensitive drum 101 further in the rotation direction of the photosensitive drum 101 than the light beam irradiation position. The toner image is transferred onto a sheet as a transfer material by a transfer roller 119 disposed below the photosensitive drum 101 so as to face the photosensitive drum 101.
[0030]
The paper is stored in a paper cassette 112 in front of the photosensitive drum 101, but can be fed manually. A pickup roller 114 is provided at an end of the paper cassette 112, and feeds the paper in the paper cassette 112 to a transport path.
[0031]
A registration shutter 117 for correcting skew of the sheet and synchronizing image formation on the photosensitive drum 101 and sheet conveyance is provided in a conveyance path between the pickup roller 114 and the transfer roller 119. The sheet is fed to the position at a predetermined timing.
[0032]
The sheet on which the unfixed toner image has been transferred as described above is further conveyed to the fixing device behind the photosensitive drum 101.
[0033]
The fixing device includes a fixing roller 120a having a fixing heater (not shown) therein and a pressure roller 120b disposed so as to be in pressure contact with the fixing roller 120a. The unfixed toner image on the paper is fixed by heating while applying pressure at the pressure contact portion between the fixing roller 120a and the pressure roller 120b.
[0034]
A fixing paper discharge sensor 121 for confirming that the paper is discharged from the pressure contact portion is provided behind the pressure contact portion. Further, discharge rollers 122 and 123 are provided behind the fixing sheet discharge sensor 121 to discharge the fixed sheet.
[0035]
A photoreceptor drum 101, a charging roller 102, a developing device 103, a toner container 104, and a cleaner 105, which are integrated to be detachable from an image forming apparatus main body, are referred to as a process cartridge 107. Is mounted. Further, the process cartridge 107 has a contact (not shown) for electrically connecting to the image forming apparatus main body.
[0036]
Next, a control section of the electrophotographic printer having such a mechanism section will be described with reference to FIG.
[0037]
2, image code data created by a user or the like in a host computer (not shown) provided outside the image forming apparatus is converted into parallel or serial data through a communication line (not shown). Send it to the controller 201.
[0038]
The printer controller 201 expands the image code data sent from the host computer and converts it into image information to be sent to the printer. The printer controller 201 also issues commands to the engine control unit 202, The data is read as a status, and a print start request and a pre-feed request are made to the engine control unit 202.
[0039]
The engine control unit 202 controls the drive / stop timing of each mechanism unit in FIG. 2 and reads the input information of each sensor, so that the paper transport control unit 203, the optical system control unit 204, the high voltage control unit 205, the fixing unit temperature control unit 206, a toner absence detection unit 207, a CRG presence / absence detection unit 208, a sensor input unit 209, and a memory communication control unit 210.
[0040]
First, the paper transport control unit 203 executes driving / stopping of various motors and various rollers based on an instruction from the engine control unit 202.
[0041]
The optical system drive unit 204 executes emission of the laser 108 and drive / stop of the scanner motor based on an instruction from the engine control unit 202.
[0042]
The high-voltage control unit 205 drives / stops high-voltage charging, development, and transfer based on an instruction from the engine control unit 202.
[0043]
The fixing unit temperature control unit 206 drives / stops the fixing heater based on an instruction from the engine control unit 202.
[0044]
The sensor input unit 209 reads the input of the cassette paper presence sensor and each sensor installed on the transport path, and provides information to the engine control unit 202.
[0045]
The memory communication control unit 210 in the present embodiment is connected to the same engine control unit 202 as described above, as shown in FIG.
[0046]
FIG. 4 shows an electrical connection configuration between the engine control unit 202 of FIG. 2 and the memory communication control unit 210 and the memory unit 106 mounted on the process cartridge 107 in the present invention. The engine control unit 202 has a CPU 401 mounted thereon, and the memory communication control unit 210 has a serial signal interface unit 402. The serial signal interface unit 402 receives a memory drive signal (MEMON) 403, a data output signal (CMD) 404, and a clock signal (CLK) 405 and outputs a data input signal (STS) 406 to be supplied to the CPU 401.
[0047]
The serial signal interface unit 402 converts the address of the memory, the designation of read / write, and the data to be stored in the memory into the data output signal 404 and the data read from the memory and the processing result of the command into the data input signal 406 in time series. Let
[0048]
The memory communication control unit 210 writes / reads data to / from the memory unit 106 having a nonvolatile memory for storing data such as the number of prints in the memory communication control unit 210 in accordance with the instruction received by the serial communication interface unit 402. Access for As the memory, for example, an EEPROM can be considered. The procedure for accessing the EEPROM is as described in the section of the prior art.
[0049]
First, the printer is in a state of waiting for a print instruction from the controller 201.
If the print instruction has not been received, it is checked whether or not there is a pre-feed request from the controller 201. If the pre-feed request has been received, the motor is driven and then the feed operation is started.
[0050]
Thereafter, it is checked whether or not the paper arrives at a pre-feed sensor (not shown, disposed in the transport path between the pickup roller 114 and the transfer roller 119), and when the pre-feed sensor detects the leading edge of the paper, a wait is performed for a predetermined time. Stop the post-feed operation. At that time, the motor is stopped and a print instruction wait state is set.
[0051]
When the print instruction is received, the scanner motor (not shown) and each high voltage are started when the motor is driven again.
[0052]
When the scanner motor reaches the specified rotation, the paper is already pre-fed, so the presence or absence of the paper is checked by the pre-feed sensor.
[0053]
At this point, if there is no sheet in the pre-feed sensor, an abnormal process (such as a jam process) is performed.
[0054]
If a sheet exists in the pre-feed sensor, the sheet is conveyed while correcting the skew by the registration shutter 117. When the TOP sensor 118 detects the leading edge of the sheet, a vertical synchronization signal is output to the controller 201 after a predetermined time, and the image writing to the photosensitive drum 101 is permitted.
[0055]
Then, after waiting for a predetermined time after the fixing / discharge sensor 121 detects the trailing edge of the sheet, the high-pressure fall and the scanner motor are stopped, and then the motor of the roller drive system is stopped to stop the printing process.
[0056]
Further, a memory unit 106 is mounted on the process cartridge 107, and print data such as the number of prints and current application time are stored so that optimum process conditions such as high-pressure conditions can be obtained for each print job. It has become.
[0057]
The CPU 401 provided in the engine control unit 202 loads a program described in a ROM (not shown) in the CPU to realize processing of the engine state determining unit and the determining unit.
[0058]
FIG. 5 is a flowchart showing a processing procedure in the engine state determination means and the determination means. In this processing, during the printing operation of the printer, the memory access permission flag is turned off and the transmission of the clock signal is stopped so that the communication is not performed, whereby the data writing to the memory unit 106 can be performed in a short time. It is made to be able to end.
[0059]
First, the engine control unit 202 initializes the inside of the built-in CPU 401 (S501), and then initializes each unit of the printer (S502). Thereafter, after starting communication with the printer controller 201 (S503), a self-diagnosis is performed as to whether there is any abnormality inside the engine (S504). The abnormality referred to here is a condition that makes it impossible to drive the engine, such as a door open, a jam, or a failure. Since such a self-diagnosis is a well-known matter, detailed description thereof will be omitted.
[0060]
If there is no abnormality in step S504, the sheet conveyance system including the process cartridge 107 is driven by the sheet conveyance control unit 203 for a predetermined time (S505 to S507, and a timer is provided inside the CPU).
[0061]
Then, after the drive is performed for a predetermined time, the access of the process cartridge 107 to the memory unit 106 is permitted (S509: memory access permission flag ON). When the flag is turned on, writing / reading of data to / from the nonvolatile memory in the memory unit 106 is started. The clock speed at that time follows the communication speed determined in advance in the CPU.
[0062]
Thereafter, it monitors the print instruction from the printer controller 201 (S510), and when the print instruction is received, prohibits the process cartridge 107 from accessing the memory unit 106 (S511: memory access permission flag OFF). Thereafter, the end of the printing operation is monitored (S512), and when the printing operation ends, the process returns to step S509.
[0063]
If there is an abnormality in step S504, the process cartridge 107 is permitted to access the memory unit 106 (S513), and waits until the abnormality is eliminated (S514). When the abnormality is eliminated, access of the process cartridge 107 to the memory unit 106 is prohibited (S515), and the process proceeds to step S505.
[0064]
The initial state of the memory access permission flag is OFF.
[0065]
As a result of the self-diagnosis, if it is determined that there is an abnormality, and if the content of the abnormality is a failure, the power will not be restored with the power on.
[0066]
According to the present embodiment, the CPU in the engine control unit 202 can communicate with the memory communication control unit 210 without providing another CPU between the engine control unit 202 and the memory communication control unit 210. In addition to the cost reduction, it is possible to arbitrarily set the timing of performing communication in accordance with the resources of the CPU.
[0067]
(Embodiment 2)
Next, a description will be given of a communication control processing procedure according to the second embodiment of the image forming apparatus according to the present invention.
[0068]
According to the present embodiment, the writing of data to the memory unit 106 can be completed in a short time without hindering the printing operation by reducing the clock speed without stopping communication with the memory unit 106 even during the printing operation of the printer. Can be done.
[0069]
FIG. 6 is a flowchart showing a processing procedure in the engine state determining means and the determining means. This processing procedure is also realized by the CPU 401 provided in the engine control unit 202 loading a program described in a ROM (not shown).
[0070]
First, the engine control unit 202 initializes the inside of the built-in CPU 401 (S601), and then initializes each unit of the printer (S602). Thereafter, after starting communication with the printer controller 201 (S603), a self-diagnosis is performed to determine whether there is any abnormality inside the engine (S604). The abnormality referred to here is a condition that makes it impossible to drive the engine, such as a door open, a jam, or a failure. Since such a self-diagnosis is a well-known matter, detailed description thereof will be omitted.
[0071]
If there is no abnormality in step S604, the sheet conveyance system including the process cartridge 107 is driven for a predetermined time by the sheet conveyance control unit 203 (S605 to S607, and a timer is provided inside the CPU).
[0072]
Then, after the driving is performed for a predetermined time, the communication clock speed between the memory communication control unit 210 and the engine control unit 202 is set to CLK0 (S609). CLK0 is a communication speed previously determined inside the CPU.
[0073]
Thereafter, it is monitored that a print instruction is received from the printer controller 201 (S610), and when a print instruction is received, the communication clock speed between the memory communication control unit 210 and the engine control unit 202 is set to CLK1 (S611). ). CLK1 is a communication speed lower than CLK0 determined in advance in the CPU.
[0074]
Thereafter, the end of the printing operation is monitored (S612), and upon completion of the printing operation, the flow returns to step S609.
[0075]
If there is an abnormality in step S604, the communication clock speed between the memory communication control unit 210 and the engine control unit 202 is set to CLK0 (S613), and the process waits until the abnormality is eliminated (S614). When the abnormality is eliminated, the communication clock speed between the memory communication control unit 210 and the engine control unit 202 is set to CLK1 (S615), and the process proceeds to step S605.
[0076]
The initial setting of the communication clock speed between the memory communication control unit 210 and the engine control unit 202 is CLK1.
[0077]
As a result of the self-diagnosis, if it is determined that there is an abnormality, and if the content of the abnormality is a failure, the power will not be restored with the power on.
[0078]
The manner in which the load on the CPU is changed by changing the clock speed by performing the above processing will be described with reference to FIG. In FIG. 7, CLK <CLK ′.
[0079]
FIG. 7 shows, in order from the top, a communication clock CLK, a change in a processing target of the CPU when the communication clock CLK is used, a time spent by the CPU in normal processing when the communication clock CLK is used, a communication clock CLK ′, and a communication clock CLK. The change of the processing target of the CPU when using the 'and the time spent by the CPU in the normal processing when using the communication clock CLK' are summarized.
[0080]
It is assumed that processing for communication is performed at the falling edge of the clock CLK (CLK ′). The hatched portion in the figure indicates the time during which the CPU performs the process related to communication, and the portion without the hatched portion indicates the time during which the normal process is performed. Comparing the sum of the time spent in the normal processing, it can be seen that CLK 'having a lower clock speed can spend more time in the normal processing. That is, during the period T, the time T2 that can be spent on the normal processing by the CLK ′ with the slow clock speed is longer than the time T1 that can be spent on the normal processing by the CLK with the fast clock speed.
[0081]
If CPU resources are used for communication, such as CLK, which has a high clock speed, during a processing state that places a heavy load on the CPU, such as during a printing operation, the time that can be used for normal processing per unit time is shortened. There is a danger that it will not be possible to carry out various processes.
[0082]
Therefore, in the present embodiment, the clock speed is changed, and when CPU resources are required, the time allotted for communication is shortened.
[0083]
According to the present embodiment, the CPU in the engine control unit 202 can communicate with the memory communication control unit 210 without providing another CPU between the engine control unit 202 and the memory communication control unit 210. In addition to reducing the cost, the communication speed with the memory communication control unit 210 is continued while the communication speed is reduced even during the printing operation, so that the efficiency of communication with the memory unit can be increased.
[0084]
(Other embodiments)
In addition, even if the present invention is applied to a system including a plurality of devices (for example, a host computer, an interface device, a reader, a printer, and the like), a device including one device (for example, a copying machine, a facsimile device, and the like) May be applied.
[0085]
Further, an object of the present invention is to supply a recording medium (storage medium) in which a program code of software for realizing the above-described embodiment is recorded to a system or an apparatus, and to provide a computer (or a CPU or an MPU) of the system or the apparatus. Needless to say, the above can also be achieved by reading and executing the program code stored in the recording medium.
[0086]
In this case, the program code itself read from the recording medium realizes the function of the above-described embodiment, and the recording medium on which the program code is recorded constitutes the present invention.
[0087]
Examples of a recording medium for recording the program code and variable data such as a table include a floppy (registered trademark) disk (FD), a hard disk, an optical disk, a magneto-optical disk, a CD-ROM, a CD-R, and a magnetic tape. For example, a nonvolatile memory card (IC memory card), a ROM, or the like can be used.
[0088]
When the computer executes the readout program code, not only the functions of the above-described embodiments are realized, but also an OS (Operating System) running on the computer based on the instruction of the program code. It goes without saying that a case where the functions of the above-described embodiments are implemented by performing part or all of the actual processing by the processing described above is also included.
[0089]
【The invention's effect】
As described above, according to the image forming apparatus, the communication control method, the storage medium, and the program product according to the present invention, at least the cartridge for mounting the storage unit for storing the print information is detachably mounted. An image forming apparatus comprising: an engine control unit having a control unit (CPU) for controlling an engine unit; and a memory communication control unit for controlling communication between the storage unit and the storage unit. Engine state determining means for determining a state of the engine unit; determining means for determining an execution state of the communication in accordance with a determination result by the engine state determining means; and an engine control unit 202 in accordance with the determined execution state. Signal output for changing the clock rate of the clock signal from the memory communication control means to the memory communication control means And controlling the communication between the engine control unit 202 and the storage unit according to the state of the engine unit by operating the serial signal output unit according to the determined execution state. With this configuration, the CPU in the engine control unit 202 can communicate with the memory communication control unit without providing another CPU between the engine control unit 202 and the memory communication control unit. Can be achieved.
[Brief description of the drawings]
FIG. 1 is a schematic diagram of a laser printer to which the present invention can be applied.
FIG. 2 is a schematic block diagram of the laser printer of FIG.
FIG. 3 is an electrical connection configuration diagram of a conventional engine control unit-memory communication control unit.
FIG. 4 is an electrical connection configuration diagram of an engine control unit and a memory communication control unit according to the present invention.
FIG. 5 is a flowchart illustrating processing performed by the image forming apparatus according to the first exemplary embodiment of the present invention.
FIG. 6 is a flowchart illustrating a process according to a second embodiment of the image forming apparatus according to the present invention.
FIG. 7 is an explanatory diagram illustrating how the load on the CPU changes by changing the clock speed by the above-described processing of the communication control method of the image forming apparatus according to the present invention.
[Explanation of symbols]
106 memory unit
107 process cartridge
201 Printer controller
202 Engine control unit 202
210 memory communication control unit
402 Serial communication interface
403 Memory drive signal
404 Data output signal
405 clock signal
406 data input signal

Claims (16)

Attachment means for detachably attaching a unit equipped with at least storage means for storing print information, and an engine control unit having control means for controlling an image forming unit and a memory for controlling communication between the storage means An image forming apparatus comprising: a communication control unit;
The control means includes:
Engine state determining means for determining a state of the image forming unit;
Determining means for determining an execution state of the communication according to a determination result by the engine state determining means;
Serial signal output means for changing the clock rate of the clock signal from the engine control unit to the memory communication control means,
The image forming apparatus according to claim 1, wherein the serial signal output unit is operated in accordance with the determined execution state to control communication between the engine control unit and the storage unit. The image forming apparatus according to claim 1,
The image forming apparatus according to claim 1, wherein the serial signal output unit stops sending the clock signal when the engine state determination unit detects that the printing operation is being performed. The image forming apparatus according to claim 1,
When the engine state determination means detects that a printing operation is being performed, the serial signal output means sends the clock signal at a lower rate than the clock rate of the clock signal during standby. apparatus. The image forming apparatus according to claim 1, wherein
The image forming apparatus according to claim 1, wherein the serial signal output unit changes a data output signal from the memory communication control unit to the engine control unit according to the determined execution state. Attachment means for detachably attaching a unit equipped with at least storage means for storing print information, and an engine control unit having control means for controlling an image forming unit and a memory for controlling communication between the storage means A communication control method of the image forming apparatus comprising:
By the control means,
An engine state determining step of determining a state of the image forming unit;
A determining step of determining an execution state of the communication according to a determination result in the engine state determining step;
According to the determined execution state, operating the serial signal output unit by changing the clock rate of the clock signal from the engine control unit to the memory communication control unit, the engine control unit and the storage unit And a communication control step of controlling communication between the image forming apparatuses. The communication control method for an image forming apparatus according to claim 5,
A communication control method for an image forming apparatus, wherein the transmission of the clock signal is stopped in the communication control step when the printing operation is detected in the engine state determination step. The communication control method for an image forming apparatus according to claim 5,
An image forming apparatus that, when detecting that a printing operation is being performed in the engine state determining step, transmits the clock signal at a lower rate than a clock rate of the clock signal in a standby state in the communication control step. Communication control method. The communication control method for an image forming apparatus according to claim 5,
The communication control method of the image forming apparatus, further comprising: changing a data output signal from the memory communication control unit to the engine control unit according to the determined execution state. Attachment means for detachably attaching a unit equipped with at least storage means for storing print information, and an engine control unit having control means for controlling an image forming unit and a memory for controlling communication between the storage means A storage medium storing a program of a communication control method of the image forming apparatus having the communication control means;
The program is controlled by the control unit.
An engine state determining step of determining a state of the engine unit;
A determining step of determining an execution state of the communication according to a determination result in the engine state determining step;
According to the determined execution state, operating the serial signal output unit by changing the clock rate of the clock signal from the engine control unit to the memory communication control unit, the engine control unit and the storage unit And a communication control step of controlling communication between the storage media. The storage medium according to claim 9,
The storage medium according to claim 1, wherein the transmission of the clock signal is stopped in the communication control step when the printing operation is detected in the engine state determination step. The storage medium according to claim 9,
A storage medium, wherein when the engine state determination step detects that a printing operation is being performed, the communication control step sends the clock signal at a lower rate than the clock rate of the clock signal in a standby state. The storage medium according to any one of claims 9 to 11,
The storage medium, further comprising: changing a data output signal from the memory communication control unit to the engine control unit according to the determined execution state in the communication control step. Attachment means for detachably attaching a unit equipped with at least storage means for storing print information, and an engine control unit having control means for controlling an image forming unit and a memory for controlling communication between the storage means In a program product of a communication control method of an image forming apparatus having a communication control unit,
In the control means,
An engine state determining step of determining a state of the image forming unit;
A determining step of determining an execution state of the communication according to a determination result in the engine state determining step;
According to the determined execution state, operating the serial signal output unit by changing the clock rate of the clock signal from the engine control unit to the memory communication control unit, the engine control unit and the storage unit And a communication control step of controlling communication between the programs. The program product according to claim 13,
A program product, characterized in that when the engine state determining step detects that a printing operation is being performed, the communication control step stops sending the clock signal. The program product according to claim 13,
A program product, wherein when the engine state determination step detects that a printing operation is being performed, the communication control step sends the clock signal at a lower rate than the clock rate of the clock signal in a standby state. The program product according to claim 13, wherein
The program product, wherein the communication control step further includes changing a data output signal from the memory communication control means to the engine control unit according to the determined execution state.

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