Abstract:
A computer readable design support program for inspecting a processing operation of software that controls a sheet conveyance mechanism by displaying the behavior of feeding a virtual sheet from a virtual sheet stock portion on a display portion, includes a sheets number setting procedure of setting the sheets number of virtual sheets stored in the virtual sheet stock portion, a sheet feed display procedure of displaying the behavior of feeding the virtual sheet from the virtual sheet stock portion on the display portion, a stored sheets number subtraction procedure of subtracting the stored sheets number of virtual sheets corresponding to the virtual sheet stock portion to which the virtual sheet is supplied in the sheet feed display procedure, a judgment procedure of judging whether or not the virtual sheet is used up in the virtual sheet stock portion where the stored sheets number of virtual sheets is subtracted in the stored sheets number subtraction procedure, and a paper out display procedure of displaying on the display portion the paper out on the virtual sheet stock portion for which it is judged that the virtual sheet is used up in the judgement procedure.

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a design support method and a design support program for supporting the mechanism control design. More particularly, the invention relates to a design support program and a design support method for the software of controlling a conveyance mechanism for conveying a sheet-like carrier. 
   2. Related Background Art 
   Conventionally, the conveyance of the sheet-like carrier such as paper (hereinafter simply referred to as paper) is performed in all the fields. For instance, the paper is conveyed by the conveyance mechanism comprising a roller and a guide in the image forming apparatus such as a copier and a printer. 
   In the conveyance of the paper, in many cases, the paper is rarely conveyed in only one direction simply at an equal velocity. Usually, employing a virtual sensor for detecting the position of the carrier, for example, the paper is stopped at a prescribed position, or reversed in the direction of conveyance by reversely rotating the roller. Accordingly, the software for controlling the mechanism that conveys the paper is indispensable in conveying the paper. 
   In recent years, it is expressed that the image forming apparatus has higher performance and higher productivity, and correspondingly, the software for controlling the image forming apparatus is complicated, increasing the man-hour required for finding a trouble, specifying the cause, and making correction. 
   Thus, the chance of using the simulation technology in designing the conveyance mechanism has increased along with the enhanced performance of the computer in recent years. For instance, a system for calculating the action of paper by simulation, and finding the defect potential in the conveyance mechanism has been proposed as disclosed in Japanese Patent Application Laid-Open No. H9-81600. 
   Moreover, the proposals concerning the inspection of the software for controlling the mechanism have been made while the mechanism simulation is active in all scenes. For the inspection of the software, the reproduction of irregular situations is indispensable, in addition to the simulation of the basic operation of the paper. Because an error in software often occurs during the irregular operation rather than in the basic portion. 
   In the light of the above respect, a design support method for generating an external event of turning on/off the switch or opening or closing the cover in the printer control software from an input device such as a keyboard has been proposed as disclosed in Japanese Patent Application Laid-Open No. H5-143260. 
   However, a paper out state of the cassette storing the paper could not be reproduced in the simulator for the software inspection in the past. 
   When the paper feed from the cassette stages is inspected, the software is often troublesome in the paper out state, for which the inspection of software is indispensable. For instance, if the paper out state occurs in a certain cassette, it is required to inspect from which cassette to feed the paper at the next time. 
   Moreover, when the paper is fed from different cassettes after the paper out state of the cassette turns out, the paper feed timing is delayed from the usual paper feed, involving a difficult sequence concerning how to absorb a difference in the timing. 
   Further, in the paper out state of the cassette, most problems often occur at the specific timings, such as “there is a problem when the paper out occurs at specific sequence number of paper in feeding the paper”. In the paper out state, it is necessary to reproduce the phenomenon at the specific timings. 
   SUMMARY OF THE INVENTION 
   In order to solve the above-mentioned problems, it is an object of the invention to provide a design support program and a design support method that can generate the paper out state at arbitrary timing, and display the paper out state. 
   In order to accomplish the above object, the present invention provides a computer readable design support program for inspecting a processing operation of software that controls a sheet conveyance mechanism by displaying the behavior of feeding a virtual sheet from a virtual sheet stock portion on a display portion, comprising a sheets number setting procedure of setting the sheets number of virtual sheets stored in the virtual sheet stock portion, a sheet feed display procedure of displaying the behavior of feeding the virtual sheet from the virtual sheet stock portion on the display portion, a stored sheets number subtraction procedure of subtracting the stored sheets number of virtual sheets corresponding to the virtual sheet stock portion to which the virtual sheet is supplied in the sheet feed display procedure, a judgment procedure of judging whether or not the virtual sheet is used up in the virtual sheet stock portion where the stored sheets number of virtual sheets is subtracted in the stored sheets number subtraction procedure, and a paper out display procedure of displaying on the display portion the paper out on the virtual sheet stock portion for which it is judged that the virtual sheet is used up in the judgement procedure. 
   Also, the invention provides a design support method for inspecting a processing operation of software that controls a sheet conveyance mechanism by displaying the behavior of feeding a virtual sheet from a virtual sheet stock portion on a display portion, comprising a sheets number setting procedure of setting the sheets number of virtual sheets stored in the virtual sheet stock portion, a sheet feed display procedure of displaying the behavior of feeding the virtual sheet from the virtual sheet stock portion on the display portion, a stored sheets number subtraction procedure of subtracting the stored sheets number of virtual sheets corresponding to the virtual sheet stock portion to which the virtual sheet is supplied in the sheet feed display procedure, a judgment procedure of judging whether or not the virtual sheet is used up in the virtual sheet stock portion where the stored sheets number of virtual sheets is subtracted in the stored sheets number subtraction procedure, and a display procedure of displaying on the display portion the paper out on the virtual sheet stock portion for which it is judged that the virtual sheet is used up in the judgement procedure. 
   Other objects and features of the invention will be apparent from the following description and the drawings. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a control block diagram; 
       FIG. 2  is a detailed control block diagram; 
       FIG. 3  is a screen display image view; 
       FIG. 4  is a view for explaining a sheet conveyance simulation; 
       FIG. 5  is a diagram showing a cassette sheet window of an embodiment 1; 
       FIG. 6  is a diagram showing a display example in an A4, sheet feed sequence of the embodiment 1; 
       FIG. 7  is a diagram showing a display example for the paper out in the embodiment 1; 
       FIGS. 8A and 8B  are diagrams showing a cassette size-setting example of the embodiment 1; 
       FIG. 9  is a diagram showing a display example in an A3 sheet feed sequence of the embodiment 1; 
       FIG. 10  is a diagram showing a sheets number setting example of the embodiment 1; 
       FIG. 11  is a diagram showing a sheets number setting example of the embodiment 1; 
       FIG. 12  is a diagram showing a sheets number setting example of the embodiment 1; 
       FIG. 13  is a diagram showing a sheets number setting example of the embodiment 1; 
       FIG. 14  is a flowchart showing a sequence of the embodiment; 
       FIG. 15  is a diagram showing a cassette sheet window of an embodiment 2; 
       FIG. 16  is a view showing a display example in an A4 sheet feed sequence of the embodiment 2; 
       FIG. 17  is a diagram showing a display example for the paper out in the embodiment 2; 
       FIG. 18  is a flowchart showing a sequence of the embodiment; 2. 
       FIG. 19  is a diagram showing a cassette sheet window of an embodiment 3; 
       FIG. 20  is a diagram showing a display example for the paper out in the embodiment 3; and 
       FIG. 21  is a flowchart showing a sequence of the embodiment 3. 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   A design support apparatus of the present invention will be described below in more detail with reference to the drawings. 
   Embodiment 1 
   An embodiment 1 is firstly described. In this embodiment, when a virtual sheet is fed from a virtual cassette in a sheet conveyance simulation, it is judged whether or not the virtual cassette runs out of paper, and its judgment is displayed. Herein, the term “virtual” is employed to designate the virtual sheet and cassette on simulation. 
     FIG. 1  is a design support apparatus according to this embodiment. The design support apparatus according to this embodiment is a sheet conveyance simulator that can perform the sheet conveyance simulation for an image forming apparatus on a personal computer. Also, this design support apparatus can support a control timing design of farm software for controlling a sheet conveyance mechanism in the image forming apparatus in the actual world to enable the inspection of a processing operation of farm software. 
   A software simulation portion  1  virtually performs the farm software concerning the sheet conveyance control on the personal computer. An input monitoring portion  4  monitors the input of a keyboard device or a mouse on a man machine interface and instructs the software simulation portion  1  to start execution of the software simulation. 
   The execution result of software simulation is passed to a mechanism simulation portion  2 . The mechanism simulation portion  2  calculates at which position within the sheet conveyance mechanism the virtual sheet resides from the speed of a virtual roller involving the sheet conveyance control, and passes it to the software simulation portion  1  or a display control portion  5 . 
   The display control portion  5  displays a sheet conveyance simulation screen W 1  as shown in  FIG. 3  on a display associated with the personal computer. On the sheet conveyance simulation screen W 1 , a virtual sheet conveyance path is denoted by the dotted line, the virtual roller is denoted by circle, a virtual sensor is denoted by triangle, and the virtual sheet is denoted by the solid line P. 
   The software simulation portion  1  and the mechanism simulation portion  2  as described here are stored in an HDD or the like (not shown) of the personal computer before execution, and expanded and executed over a RAM (not shown) of the personal computer. 
     FIG. 2  shows the configuration of the software simulation portion  1  and the mechanism simulation portion  2  for the design support apparatus according to this embodiment. 
   The software simulation portion  1  comprises a farm software portion  10 , an input I/F portion  12  and an output I/F portion  13 . 
   The farm software portion  10  is the software for making the sheet conveyance control of the image forming apparatus in the actual world. The input I/F portion  12  inputs the information from the mechanism simulation portion  2 . The output I/F portion  13  outputs the information to the mechanism simulation portion  2 . 
   The mechanism simulation portion  2  comprises a sheet position calculation portion  20 , an input I/F portion  29 , an output I/F portion  27 , and a sheet position display portion  28 . 
   The input I/F portion  29  accepts the output result from the output I/F portion  13  of the software simulation portion  1 , and passes the control information of various devices such as a virtual motor, a virtual clutch, and a virtual flapper involving the sheet conveyance control to the latter stage. 
   The sheet position calculation portion  20  calculates a conveying speed on the virtual sheet conveyance path from the control information of the virtual motor, the virtual clutch and the virtual flapper involving the sheet conveyance control, and calculates the leading position and the trailing position of the virtual sheet. 
   The sheet position display portion  28  instructs the display control portion  5  to display the sheet conveyance simulation screen W, based on the leading position and the trailing position of the virtual sheet that are calculated by the sheet position calculation portion  20  at the former stage. 
   The output I/F portion  27  gives the sheet position information set by the sheet position calculation portion  20  at the former stage to the input I/F portion  12  of the software simulation portion  1 . 
   Referring to  FIG. 4 , the actual simulation operation will be described below.  FIG. 4  is an arrangement example of various devices regarding the sheet conveyance control. In the simulation, it is premised that the virtual sheet P is conveyed in a direction of the arrow of the solid line on the path AB by the virtual roller R 1 , and moved to the path BC or path BD by switching the virtual flapper FL 1  at a timing when the leading edge of the virtual sheet P passes the virtual sensor S 1 . The virtual roller R 1  is driven from the virtual motor M 1  via the virtual clutch CL 1 . The arrow of the dotted line indicates the driving relation. 
   If the designer instructs to start the sheet conveyance simulation from the keyboard or mouse on the man machine interface, the software simulation portion  1  and the mechanism simulation portion  2  are executed via the input monitoring portion  4 . If the software simulation portion  1  is started the farm software portion  10  successively executes the software for making the sheet conveyance control of the image forming apparatus in the actual world in cooperation with a wrapper portion  11 . 
   If a process of rotating the virtual motor M 1  is started in the farm software portion  10 , the ID number specifying the virtual motor M 1 , the rotation speed and the rotation direction are given as a command via the output I/F portion  12  to the input I/F portion  23  of the mechanism simulation portion  2 . The input I/F portion  23  interprets the command, and passes it to the sheet position calculation portion  20 . 
   The sheet position calculation portion  20  starts the rotation of the virtual motor M 1 , and calculates the rotation speed and the rotation direction by retrieving the virtual roller or virtual clutch driven by the virtual motor M 1 . Since the virtual roller R 1  is driven via the virtual clutch CL 1 , the information of the rotation speed and rotation direction of the virtual roller R 1  is calculated based on the ON/OFF information of the virtual clutch CL 1 . 
   The sheet position calculation portion  20  calculates the leading and trailing positions of the virtual sheet P at a regular interval t. First of all, the information of the path AB including the leading edge to the trailing edge of the virtual sheet P is acquired. The path information also includes the ID of the virtual roller within each path and its positional information, in which the virtual roller is retrieved in a direction from the leading position to the trailing position of the virtual sheet P, and the speed v corresponding to the ID of the virtual roller R 1  found firstly is acquired. The position of the virtual sheet P is updated by calculating the distance S=v×t by which the virtual sheet P advances from the speed v and the time interval t. The updated position information is passed to the sheet position display portion  28 , and displayed on the sheet conveyance simulation screen W 1 . 
   The path information also includes the ID of the virtual sensor within each path and its positional information. The sheet position calculation portion  20  retrieves the virtual sensor in the direction from the leading position to the trailing position of the virtual sheet P, and sends the ON information of the virtual sensor S 1  found to the output I/F portion  27 . Also, the OFF information of the virtual sensor S 1  is sent to the output I/F portion  27  in a state where the trailing edge of the virtual sheet P passes the virtual sensor S 1 . 
   The output I/F portion  27  makes a command from the ON information or OFF information of the virtual sensor S 1  and outputs it to the input I/F portion  12  of the software simulation portion  1 . 
   The farm software portion  10  receives the ON information of the virtual sensor S 1  from the input I/F portion  12 , and starts to control the virtual flapper FL 1 . The command is also sent to the mechanism simulation portion  2  in the same way as the virtual motor M 1 . Upon receiving a control command of the virtual flapper FL 1 , the sheet position calculation portion  20  decides the next path for advancement if the leading edge of the virtual sheet P reaches a branch point B, and judges whether the advancing direction of the virtual sheet P is the path BC or path BD depending on a switched state of the virtual flapper FL 1 . 
   In  FIG. 5 , reference numeral  500  designates a cassette sheet window. This window is employed in referring to the settings of virtual sheet in the virtual cassettes and the current state of virtual sheet in the virtual cassettes. Reference numerals  510  to  513  designate the name columns. The name of each virtual cassette is displayed here. Reference numerals  520  to  523  designate the size columns. The size information of the virtual sheet existing within each virtual cassette is displayed here. Reference numerals  530  to  533  designate the sheet type columns. The information of sheet type existing within each virtual cassette is displayed here. Reference numerals  540  to  543  designate the sheets number columns. The number of virtual sheets (sheets number information) existing within each virtual cassette is displayed here. 
     FIG. 6  is a display when the sheet feed simulation of one sheet from the virtual cassette  3  is performed from the state of  FIG. 5 . In  FIG. 6 , how the cassette sheet window of  FIG. 5  and the sheet conveyance simulation screen of  FIG. 3  are changed are shown. 
   In the sheet feed from the virtual cassette  3  from the state of  FIG. 5 , the sheet is fed from the corresponding virtual cassette  3  ( 603 ). Reference numeral  601  corresponds to the virtual cassette  1 ,  602  corresponds to the virtual cassette  2 , and  604  corresponds to the virtual cassette  4 . Reference numeral  650  designates the virtual sheet, in which the sheet is fed from the virtual cassette  3 , and slightly moved. At this time, since the sheet size information of the virtual cassette  3  is A4, the length of sheet is equivalent to A4. 
   If the sheet is fed from the virtual cassette  3 , the stored sheets number (sheets number information) of virtual sheets within the virtual cassette  3  is decremented, and displayed like  642  in less quantity than  542  in  FIG. 5 . In this way, the stored sheets number (sheets number information) of virtual sheets is decremented every time the sheet is fed, and corresponding displayed in decremented quantity. Also, this processing is performed every time the sheet is fed. 
   If the sheet is fed from the virtual cassette in this way, the sheet feed simulation is made from the corresponding virtual cassette, and displayed, while the sheets number information of the corresponding virtual cassette is decremented, and displayed. This is similarly performed for other virtual cassettes. 
     FIG. 7  is a display when the sheets are further fed from the virtual cassette  3  via the state from  FIG. 5  to  FIG. 6 . Though the sheets number within the virtual cassette is decremented every time the sheet feed simulation is made as previously described in connection with  FIG. 6 , the sheets are continued so that the sheets number information reaches 0 in  FIG. 7 . 
   In  742 , the sheets number indication is 0 and displayed in black and white reversal to be easily seen from the user. Also, cassette  3 : “paper out” is displayed corresponding to the virtual cassette  3  on the right sheet conveyance simulation screen, and the virtual cassette and the virtual roller within the virtual cassette are emphasized in the bold line to be easily seen from the user. 
   When the paper out occurs, a paper out state is notified from the output I/F portion  27  of the mechanism simulation portion  2  of  FIG. 2  to the input I/F portion  12  of the software simulation portion  1 . Thereby, the paper out is recognizable from the farm software portion  10 , which can perform a process for recognizing the paper out. 
   Referring to  FIGS. 8A and 8B , the switching of size within the virtual cassette will be described below.  FIG. 8A  is a screen when a part  522  of the sheet size indication corresponding to the virtual cassette  3  is clicked from the state of  FIG. 5 . If the part  522  ( 822   a  in  FIG. 8A ) is clicked, a selection box  870  appears under  822   a  as shown in  FIG. 8A . If the size is selected from this selection box, the size information of the virtual sheet is changed to the selected size, which is informed via the output I/F portion  27  of the simulator portion of  FIG. 2  and the input I/F portion  12  of the software simulation portion  1  to the farm software portion  10 . The display of the sheet position display portion  28  is also changed. 
     FIG. 8B  is a screen after A3 is selected in  870  from the state of  FIG. 8A . In  FIG. 8B , the indication is changed to A3 in  822   b.    
     FIG. 9  is a display when the sheet feed simulation of one sheet from the virtual cassette  3  is made from the state of  FIG. 8B . The sheets number information is decremented by one in the same way as when the sheet feed simulation is made from the settings of  FIG. 5 , whereby the indication of  942  is decreased from 100 to 99. In the right sheet conveyance simulation, because the sheet size information of the virtual cassette  3  is A3 at this time, the virtual sheet  950  has the length corresponding to A3. A difference from the length of the virtual sheet  650  of A4 size in  FIG. 6  is apparent. 
   As seen from  FIG. 9 , the actual simulation and its display are reflected by changing the sheet size of the virtual cassette as described in connection with  FIGS. 8A and 8B . 
   Though not described in detail here, if the sheets number information reaches 0 in this simulation of A3, naturally, the paper out state and its display as described in connection with  FIG. 7  become effective, whereby the paper out state through the simulation with different sheet size can be regenerated. 
   Also, though not described in detail here, the sheet type information of  530  to  533  in  FIG. 5  is notified to the farm and the display is updated in the same way as when the sheet size is changed as described above. 
   Referring to  FIGS. 10 to 13 , the settings of the sheet size within the virtual cassettes will be described below.  FIG. 10  shows a cassette sheet window. In this window, the item  1042  corresponding to the virtual cassette  3  is taken as an example. 
   In  FIG. 10 , reference numeral  1061  designates a sheets number up button. If this button is pressed, the sheets number information of the virtual cassette  3  is incremented by one, and the indication of  1042  is also incremented by one.  FIG. 11  shows a display when the sheets number up button  1061  is pressed once in  FIG. 10 . In  FIG. 11 , the indication of  1043  is changed to 101. 
   In  FIG. 10 , reference numeral  1062  designates a sheets number down button. If this button is pressed, the sheets number information of the virtual cassette  3  is decremented by one, and the indication of  1042  is also decremented by one.  FIG. 12  shows a display when the sheets number down button  1062  is pressed once in  FIG. 10 . In  FIG. 12 , the indication of  1044  is changed to 99. 
   Also, if the item  1042  of  FIG. 10  is clicked, one can write a favorite number into the item, whereby the sheets number information can be set to the favorite value.  FIG. 13  shows a display when  1042  is clicked and 50 is entered. In  FIG. 13 , the indication of  1045  is changed to 50. 
   Though not described in detail here, if the sheets number information reaches 0 in this sheets number information simulation, naturally, the paper out state and its display as described in connection with  FIG. 7  become effective, whereby the paper out state through the sheet feed simulation with different sheets number can be regenerated. 
   Referring to  FIG. 14 , a sequence of the simulator in this embodiment will be described below. This sequence involves a process of feeding the sheet in the simulation, and rises when this simulator is started. Also, this sequence is provided for every virtual cassette, whereby the number of sequences is equal to the number of virtual cassettes. 
   First of all, at step S 1501 , it is judged whether or not the sheet is fed. This simulator monitors the input state from the input I/F portion  29  on the mechanism simulation portion  2  via the output I/F portion  13  from the software simulation portion  1  of  FIG. 1 , whereby it is judged whether or not the state corresponds to the sheet feeding. If it is judged at step S 1501  that the sheet is not fed, step S 1501  is repeated until the sheet feed is ready. 
   If it is judged at step S 1501  that the sheet is fed, the sheet size of the virtual cassette is read at step S 1502 . Then, at step S 1503 , the virtual sheet of the sheet size information read at step S 1502  is prepared. If the virtual sheet is prepared at step S 1503 , the virtual sheet prepared at step S 1503  is displayed ( 650  in  FIG. 6 ,  950  in  FIG. 9 ). 
   If step S 1504  is ended, the sheets number information is decremented by one at step S 1505 . After the end of step S 1505 , the indication of sheets number information is updated at step S 1506  ( 542  of  FIG. 5 to 642  of  FIG. 6 ). After the end of step S 1506 , it is judged whether or not the sheets number information of this virtual cassette reaches 0 at step S 1507 . If it is judged at step S 1507  that the sheets number information does not reach 0, the procedure returns to step S 1501  to become a sheet feeding wait state. If it is judged at step S 1507  that the sheets number information reaches 0, the procedure goes to step S 1508  to notify the paper out information through the output I/F portion  27  and the input I/F portion  12  of  FIG. 2  from the mechanism simulation portion  2  to the software simulation portion  1 . 
   If step S 1508  is ended, the “paper out” is displayed by the display control portion  5  at step S 1509  ( 742  and  703  in FG.  7 ). If step S 1509  is ended, the procedure is ended. 
   If the procedure is ended here, the display control portion  5  cancels the display of “paper out” when the virtual sheets within the virtual cassette are reset separately and the sheets number information is not zero. And the canceled paper out state is notified through the output I/F portion  27  and the input I/F portion  12  of  FIG. 2  from the mechanism simulation portion  2  to the software simulation portion  1 , and this sequence is started again. 
   As described above, in this embodiment, the paper out state turns effective at the timing when the virtual sheet runs out, whereby the minute sheet conveyance simulation is enabled. Also, the sheet size and the sheets number can be set as the sheet information of the virtual cassette, whereby various simulations can be performed simply and the paper out state through the simulation can be implemented. Thereby, the inspection efficiency of the farm software can be improved. 
   Embodiment 2 
   In an embodiment 2, the basic configuration is the same as in the embodiment 1. Hence, different points from the embodiment 1 are only described by quoting the contents of the embodiment 1. The explanation up to  FIG. 4  is the same as in the embodiment 1, and omitted here. 
     FIG. 15  is a screen of a cassette sheet window in this embodiment. Since the items  1200  to  1233  are equivalent to the items  500  to  533  in  FIG. 5 , other items will be described. Reference numerals  1240  to  1243  designate the initial sheets number columns, where the initial value of the sheets number contained in the virtual cassette is indicated. Reference numerals  1280  to  1283  designate the fed sheets number columns for indicating the number of fed sheets. 
     FIG. 16  is a display when the sheet feed simulation of one sheet from the virtual cassette  3  is performed from the state of  FIG. 5 . The items  1301  to  1304  and  1350  are equivalent to the items  501  to  504  and  550  of  FIG. 5 , and the item  1382  will be only described here. 
   If the sheet is fed from the virtual sheet cassette  3 , the fed sheets number of the virtual cassette  3  is incremented, so that the indication of  1382  is incremented by one as compared with  1282  of  FIG. 15 . The fed sheets number information is incremented every time the sheet is fed in this way, and the indication is increased correspondingly. Also, this processing is performed every time the sheet is fed. This processing is also performed for other virtual cassettes. 
     FIG. 17  is a display when the sheet is fed consecutively from the virtual cassette  3  through the state from  FIG. 15  to  FIG. 16 . Though the fed sheets number is incremented every time the simulation of sheet feeding is performed as described with  FIG. 15 ,  FIG. 17  shows a state when the sheet is fed consecutively so that the fed sheets number information is equal to the initial sheets number. In  1482 , the sheets number indication is  100  and displayed in black and white reversal to be easily seen from the user. Moreover, the initial sheets number  1442  of the virtual cassette  3  is also displayed in black and white reversal. 
   Also, cassette  3 : “paper out” is displayed corresponding to the virtual cassette  3  on the right sheet conveyance simulation screen, and the virtual cassette and the virtual roller within the virtual cassette are emphasized in the bold line to be easily seen from the user. 
   Also, when the paper out occurs, a paper out state is notified through the output I/F portion  27  and the input I/F portion  12  of  FIG. 2  from the mechanism simulation portion  2  to the software simulation portion  1 . Thereby, the paper out is recognizable from the farm software portion  10 , which can perform a process for recognizing the paper out. 
   Also, in this embodiment, the sheet size can be changed by selection in the same way as in  FIGS. 8A and 8B  of the embodiment 1. Also, the initial sheets number and the fed sheets number can be directly inputted or increased or decreased by a button in the same way as in  FIG. 10  of the embodiment 1. Hence, the details thereof are not described in this embodiment. 
   Referring to  FIG. 18 , a sequence of this embodiment will be described below. This sequence involves a process of feeding the sheet in the simulation, and rises when this simulator is started. Also, this sequence is provided for every virtual cassette, whereby the number of sequences is equal to the number of virtual cassettes. First of all, at step S 1501 , it is judged whether or not the sheet is fed. 
   This simulator monitors the input state from the input I/F portion  29  on the mechanism simulation portion  2  via the output I/F portion  13  from the software simulation portion  1  of  FIG. 1 , and it is judged whether or not the state corresponds to the sheet feeding. If it is judged at step S 1501  that the state is not the sheet feeding, step S 1501  is repeated until the state is the sheet feeding. If it is judged at step S 1501  that the sheet is fed, the sheet size of the virtual cassette is read at step S 1502 . Then, at step S 1503 , the virtual sheet of the sheet size information read at step S 1502  is prepared. 
   If the virtual sheet is prepared at step S 1503 , the virtual sheet prepared at step S 1503  is displayed ( 1350  in  FIG. 16 ). If step S 1504  is ended, the sheets number information is incremented by one at step S 1505 . After the end of step S 1505 , the indication of sheets number information is updated by the display control portion  5  at step S 1506  ( 1282  of  FIG. 15 to 1382  of  FIG. 16 ). After the end of step S 1506 , it is judged whether or not the sheets number information of this virtual cassette reaches the initial sheets number at step S 1507 . If it is judged at step S 1507  that the sheets number information does not reach the initial sheets number, the procedure returns to step S 1501  to become a sheet feeding wait state. 
   If it is judged at step S 1507  that the sheets number information is equal to the initial sheets number, the procedure goes to step S 1508  to notify the paper out information through the output I/F portion  27  and the input I/F portion  12  of  FIG. 2  from the mechanism simulation portion  2  to the software simulation portion  1 . If step S 1508  is ended, the “paper out” is displayed at step S 1509  ( 1442 ,  1482  and  1403  in  FIG. 17 ). If step S 1509  is ended, the procedure is ended. If the procedure is ended here, the virtual sheets (fed sheets number or initial sheets number) within the virtual cassette are reset separately, and when the fed sheets information is not equal to the initial sheets number, this sequence is started again. 
   As described above, in this embodiment, the paper out state turns effective at the timing when the virtual sheet runs out, whereby the minute sheet conveyance simulation is enabled. Also, the sheet size and the sheets number can be set as the sheet information of the virtual cassette, whereby various simulations can be performed simply and the paper out state through the simulation can be implemented. Thereby, the inspection efficiency of farm software can be improved. 
   Embodiment 3 
   In an embodiment 3, the basic configuration is the same as in the embodiment 1. Hence, different points from the embodiment 1 are only described by quoting the contents of the embodiment 1. The explanation up to  FIG. 4  is the same as in the embodiment 1, and omitted here. 
     FIG. 19  is a screen of a cassette sheet window in this embodiment. Since the items  1600  to  1223  are equivalent to the items  500  to  523  in  FIG. 5 , other items will be described. Reference numerals  1690  to  1693  designate the paper out generation buttons. If this button is pressed, the paper out state is compulsorily generated in the corresponding virtual cassette. 
     FIG. 20  is a display when a paper out generation button  1692  corresponding to the virtual cassette  3  is pressed in  FIG. 19 . The button is displayed in black and white reversal like  1792 . Also, cassette  3 : “paper out” is displayed corresponding to the virtual cassette  3  on the right sheet conveyance simulation screen, as indicated by  1703 , and the virtual cassette and the virtual roller within the virtual cassette are emphasized in the bold line to be easily seen from the user. 
   Also, when this paper out occurs, a paper out state is notified from the output I/F portion  27  of the mechanism simulation portion  2  to the input I/F portion  12  of the software simulation portion  1  as shown in  FIG. 2 . Thereby, the paper out is recognizable from the farm software portion  10 , which can perform a process for recognizing the paper out. In this situation, if the button  1792  is pressed once more, the black and white reversal display is returned to its original state, and the paper out indication in the right figure is also canceled. And the paper out cancel is notified from the output I/F portion  27  of the mechanism simulation portion  2  to the input I/F portion  12  of the software simulation portion  1  as shown in  FIG. 2 , and the original state is restored. 
   Also, in this embodiment, the sheet size can be changed by selection in the same way as in  FIGS. 8A and 8B  of the embodiment 1. 
     FIG. 21  is a flowchart for explaining a sequence of this embodiment. This sequence involves a process of generating the paper out in the simulation, and rises when this simulator is started. Also, this sequence is provided for every virtual cassette, whereby the number of sequences is equal to the number of virtual cassettes. 
   First of all, at step S 1807 , it is judged whether or not the paper out button corresponding to the virtual cassette is pressed. If it is judged at step S 1807  that the button is not pressed, step  1807  is repeated until the button is pressed. If it is judged at step S 1807  that the paper out button is pressed, the paper out information is notified through the output I/F portion  27  and the input I/F portion  12  of  FIG. 2  from the mechanism simulation portion  2  to the software simulation portion  1  at step S 1808 . 
   If step S 1808  is ended, the “paper out” is displayed by the display control portion  5  at step S 1809  ( FIG. 20 ). After the end of step S 1809 , the procedure is ended. If the procedure is ended here, the paper out cancel is notified through the output I/F portion  27  of the mechanism simulation portion  2  and the input I/F portion  12  of the software simulation portion  1  to the farm software portion  10 , when the button  1792  of  FIG. 20  is pressed again. Moreover, the “paper out” indication as shown in  FIG. 20  is canceled by the display control portion  5 , and this sequence is started again. 
   As described above, in this embodiment, the paper out state can be generated by the input from the user, whereby the more minute sheet conveyance simulation is enabled than the conventional simulation in which the paper out is not generated. 
   Also, the paper out state can be generated at arbitrary timing and the paper out state can be displayed, whereby the inspection efficiency of the farm software controlling the sheet conveyance mechanism can be improved. 
   This application claims priority from Japanese Patent Application No. 2004-297706 filed Oct. 12, 2004, which is hereby incorporated by reference herein.