Abstract:
A pointing device for rapid moving control of a cursor on a single axis, including an axis X inhibit key and an axis Y inhibit key to respectively control a specific pin of one of the input/output ports of the associated CPU to match with software program such that when one inhibit key is pressed the amount of movement of the pointing device on one axis is cleared to allow the cursor move along the direction of the other axis.

Description:
This application is a continuation of application Ser. No. 07/315,743 filed Feb. 27, 1989 now abandoned. 
    
    
     BACKGROUND OF THE INVENTION 
     This invention relates to a pointing device for rapid movement control of a visible cursor on a single axis on a display screen and, more particularly to a pointing device which includes two additional inhibit control keys for use with an interactive display oriented computer system to respectively clear the displacement signal on the axis X or the axis Y so as to let the visible cursor rapidly complete the movement on the other free axis. 
     Regular pointing devices, such as optical mouses or digitizers, are for use with computer system to provide movement for a visible cursor from position to position on a display screen of such a system. 
     In spplication, it is rather difficult by means of regular point devices to draw a straight line along the axis X or the axis Y or to draw an axial line. If to drive the mouse with a hand to draw a line directly, it will take much time to complete, and because the hand may be not very stable, the position deviation may exist. In this case, the common method is to stop hand driving and to use a special function key on the mouse for coordinate positioning at a preselected target point and then to press on another functional key to connect the line. According to this method, one should have to operate one and more function keys while the original function is temporarily stopped. Further, it is not very easy to set a target point on a coordinate. If any error in setting of target point, the deviation of line should be eliminated and the process should be repeated again. It is also very difficult to find the original initiation position when to return to hand drawing function. 
     In order to solve the said problems, the present invention provides special function key with the mouse to control quick movement of the visible cursor along a single axis on a display screen. For example, under a hand drawing function, when to drive a cursor to move along vertical direction (axis Y), it is simply to press on an inhibit key of INH-Y to allow the cursor be driven to rapidly move upward or downward (axis Y). If the moving track of the mouse is inclined or becomes tortuous due to vibration of the hand or control error, because all horizontal deviation (axis X) of the mouse will be cleared by the microprocessor during the operation and only the vertical (axis Y) displacement signal is set to the main processor, when the computer receives any signal, it will determine that the mouse is exclusively for vertical (axis Y) displacement, and the cursor will be accurately driven to move along vertical (axis Y) direction. 
     SUMMARY OF THE INVENTION 
     The present invention is to provide a pointing device for rapid movement control of a cursor on a single axis, which includes an axis X inhibit key and an axis Y inhibit key to respectively control two input/output pins of the microprocessor so as to clear the variation amount of displacement of the pointing device on the axis X or the axis Y, and to let the variation signal of displacement on the other axis be sent to the main processor to drive the visible cursor for quick moving along single axis on the monitor. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a regular flow chart. 
     FIG. 2 is a modified flow chart of the present invention. 
     FIG. 3 is a circuit diagram of the present invention. 
     FIG. 4 illustrates the assembly language of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring to the system flow chart of regular pointing device (optical mouse). When power is set (switched on), the system is initiated and the clock is started to provide required timing pulse. The primitive transmission speed is set up accordingly. Through the judgment to provide high or low potential output, the system enters the read-in function key state (hand drawing or pointing coordinate function etc.), to change the function code. The next process is to read-in the position assembly state of the mouse on the axes X and Y. The assembly state of the axes X and Y varies with the methods applied by system manufacturers. For example, in optical input process, there are coordinate variation input method, matrix comparison input method, etc. Although there are numerous reading method for the X and Y position assembly, after passing through through software arrangement and microprocessor processing, it will obtain the same result, that is, the change of the direction and amount of movement of the cursor on the axes X, Y is discomposed into X and Y direction displacement signals and transmitted to the main processor. The present invention is to clear the direction displacement signal for the axis to be inhibited letting the direction displacement signal for the other axis be transmitted to the main processor for driving the movement of the cursor. The flow chart of the present invention is to be set between Point A and B in the flow chart of FIG. 1. 
     Referring to the flow chart of the present invention as shown in FIG. 2, the initial and the end of the flow chart are respectively connected to the flow chart of FIG. 1. 
     Referring to the circuit diagram of the present invention as shown in FIG. 3, in the present embodiment, a 8048 microprocessor is used as the control center for the mouse. Except the additional axis X inhibit key (INH-X) and axis Y inhibit key (INH-Y), the mouse has a structure same as the prior art. The pins P10 to P18 of the I/O Port #1 of the CPU 8048 are for receiving the assembly signal of the mouse on X, Y position. The signal source may vary with the system used, as previously described. The pin P27 of the Port #2 is to transmit to the main processor the X and Y direction displacement signal obtained from the micro processor. The three switches SW1, SW2, and SW3 are the same as the prior art and not the scope of the present invention. The additional keys of INH-X and INH-Y are to respectively control the pins P20 and P21 of the Port #2 of the CPU 8048. 
     Please refer to the assembly language applied in the present invention as shown in FIG. 4, matching with the flow chart of FIG. 2. When CPU 8048 reads in the assembly state of the mouse on the axes X and Y and obtained the amount of movement on X and Y direction (FIG. 1), it enters the flow chart to judge if under inhibit state. 
     
         ______________________________________CHECK - INHSEE IF - X IN A,P2       To judge if the amount changed on X       direction is to be inhibited. To read P2 state       in the register A.ANL A,#00000001B       to let the content of register A be with the       value 00000001 for AND operation. In the       present embodiment, INH-X is transmitted       to the pin P2O of the CUP (FIG. 3). If the       key is pressed on, the signal from P2O is 0,       and the value after operation becomes       0000000 (zero); otherwise it becomes       00000001 (not zero).JNE SEE IF - Y       If the axis X is not to be inhibited (the value       of the operation is not zero), it skip directly       to SEE IF-Y program section.MOV R0,#Xcount       If the axis X is to be inhibited (the value of       the operation is zero), it directs to the       address of the X count.CLR A       To clear the register A to become 0.MOV @R0,A   To clear the address for X count to 0.SEE IF-Y IN A,P2       To judge if the amount changed on Y       direction is to be inhibited. To pick up the       P2 state with the value 00000010 for AND       operation.JNE NORMAL-1       If the resulted from the operation is not       zero, the axis Y should not be inhibited,       then, it is to skip to normal program       section.NOV R0,#Y count       If the result of the operation is zero, it       means that the axis Y should be inhibited.       Then, the content of the Y count is cleared       to become 0, same as the function on axis X       inhibit.CLR AMOV 2R0,ANORMAL-1    To continuously execute the normal       program:::______________________________________ 
    
     As per above description, if axis X (or axis Y) is inhibited, its amount varied will be cleared to become φ, therefore, only the amount varied on the axis Y (or the axis X) will be transmitted to the computer to drive the cursor move on Y direction (or X direction).