JP2601944B2 - Pointing device counting method - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a counting method for detecting relative movement of a pointing device such as a mouse.

[Conventional technology]

For example, a mouse is a personal computer (hereinafter, referred to as a personal computer).
It is used as an input device of a personal computer (PC), and its configuration is as shown in FIG. That is, the mouse 1 includes two button switches 3 in addition to the rotation sensors 2a and 2b as a pulse generating mechanism. The rotation sensors 2a and 2b are each composed of two rotary encoders connected to a rotation shaft of a roller that slides on an outer surface of the ball 4 that is rotatable in an arbitrary direction. A pulse signal is output from the rotary encoder in accordance with the rotation of the ball 4. It is output as rotation information in the X and Y directions. Although an example of a mouse having a mechanical configuration is shown here, the mouse is also used for an optical optical mouse and the like.

Output signals of the rotation sensors 2a and 2b and the button switch 3 are transmitted to a personal computer via a cable. A mouse interface 7 is provided in the personal computer body 5, and each signal from the mouse 1 is taken in by the mouse interface 7 and converted into a predetermined signal format. Read as requested.

Then, a pulse signal is output from the rotary encoder in accordance with the forward / backward movement of the mouse 1 in the moving direction (ie, the X direction and the Y direction), and the forward / backward moving amount is detected. This detection pulse is read by the CPU 6 while interrupting (for example, 100 μS) at regular intervals, and the cursor on the screen is moved according to the movement value. As a result, processing of graphics can be performed easily and efficiently in a short time as compared with a case where a cursor key on a keyboard is operated.

When counting the amount of mouse movement, there are a hardware method in which a logic circuit is assembled and a software method in which a program is executed by a CPU. In the case of using hardware, although there is an advantage that the count following can be performed at high speed depending on the circuit configuration, there is a problem that the configuration is complicated, which increases the cost and the size of the apparatus. On the other hand, in the software method, although the dedicated circuit for the mouse can be partially omitted, since the mouse output is captured by the interrupt of the CPU, the time available for the mouse due to the balance with other work of the CPU There is a limit. For this reason,
The detection time for a mouse must be, for example, about 100 μS intervals.

Normally, the mouse is operated at a speed of 1 m / s, which needs to be constantly detected. For this reason, the detection time due to the interruption cannot be made shorter than about 100 μS. For this reason, processing cannot be interrupted by an interrupt as in serial communication by software.

On the other hand, the resolution of the mouse was conventionally about 200 CPI (timer interrupt period = 100 μS), but recently, 400 CPI
Degree is required. However, for this purpose, the timer interrupt cycle needs to be 50 μS. However, as described above, shortening the interrupt cycle has a large effect on other processes, and cannot be shortened in practice.

By the way, in the counting process, the relative movement (movement amount from the previous position) is detected by using the two-phase pulses XA (YA) and XB (YB) from the mouse 1. Normally, one of XA and XB changes, and counting is performed on this one.

FIG. 5 is a flowchart showing a conventional count process for mouse output.

First, the current A-phase and B-phase states are input from the mouse 1 (step 21), and these are compared with the previous A-phase and B-phase states (step 22). It is determined whether or not there is (step 23). When a change in the + direction is determined (step 24), the counter is incremented by +1 (step 25).
To

If a change in the negative direction is determined (step 2
6) The counter is set to -1 (step 27). And
If the direction of + or-cannot be determined while it is determined that there is a change, the process ends with no change (step 2).
8).

Incidentally, those related to this type of technology, for example, JP-A-60-181820, JP-A-61-210418, JP-A-62-139033,
JP-A-62-198921 and JP-A-1-185714.

[Problems to be solved by the invention]

However, in the above-described conventional technology, when the mouse moves at a high speed, both the A and B phases change, and when a pulse of two or more counts is generated during the timer interrupt period, the correct count is performed. Can not.

That is, as shown in the error counting method of FIG. 3, when the generation cycle of XA (YA) and XB (YB) becomes short, the count value becomes ± 0, and the PC stops even though the mouse is moving. Is determined.

SUMMARY OF THE INVENTION An object of the present invention is to provide a counting method for a pointing device that is capable of accurately performing a counting process even when the pointing device is operated at high speed, in view of the above-described circumstances of the related art. .

[Means for solving the problem]

In order to achieve the above object, the present invention provides a pointing device that outputs a moving direction and a relative moving amount as a two-phase pulse signal, when two-phase state changes are simultaneously detected and the moving direction cannot be specified. The skip count is performed according to the previous moving direction.

[Action]

According to the above-described means, when two-phase signals are detected simultaneously with the high-speed movement of the pointing device, the previous movement direction is used, and skip counting is performed in accordance with the direction. Therefore, even in a situation where tracking by a timer interrupt cannot be performed by software, the counting process is performed while the vehicle is moving, so that high-speed tracking can be performed.

〔Example〕

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a flowchart showing a pointing device counting method according to the present invention.

First, the movement detection values of the current A-phase and B-phase are input from the mouse 1 (step 11), and this is compared with the previous movement detection values of the A- and B-phases (detected values 100 μS earlier) ( step 1
2) It is determined whether there is a change in the result (step 13). If the result of the determination is that it is in the + direction (step 14),
The soft counter is set to +1 (step 15), the + direction flag is set (step 16), and the process is terminated.

On the other hand, if it is not the + direction, it is determined whether it is the-direction (step 17). If the direction is negative, set the counter to
(Step 18), and set the -direction flag (Step 18).
19) and end the processing.

If it is neither + nor-, it is checked whether the previous moving direction was + or-(step 20).
If it is in the + direction, the counter is set to +2 (step 21), and-
If so, the counter is set to -2 (step 22), and the process is terminated.

FIG. 2 is an explanatory diagram showing the counting process according to the present invention, and FIG. 3 is a timing chart of the skip counting method.

As shown in FIG. 2, XA (YA), XB (Y
There are four states this time corresponding to 0 and 1 in (B) (XB = 0, XA
= 0, XB = 0, XA = 1, XB = 1, XA = 0, XB = 1, XA = 1),
The detection value for this is -1,0, + 1, + 2 in the + direction.
There are four types (+1, 0, -1, -2 in the case of-direction).

For example, as shown in FIG. 3, conventionally, the detection value was 0 at the tenth sampling point, whereas in the present invention, the previous movement direction at step 20 in FIG.
Confirm the direction, and set the count value to -2. As a result, as shown in the skip count method of FIG.
The cumulative count value at the 10th sampling point is 0
(Conventionally +2). Therefore, what is conventionally determined to be stopped is processed as if it is moving in the minus direction in the present invention, and the cursor is moved and displayed on the screen.

〔The invention's effect〕

As is clear from the above, according to the present invention, in a pointing device that outputs a moving direction and a relative moving amount as a two-phase pulse signal, when two-phase state changes are simultaneously detected and the moving direction cannot be specified, Since skip counting is performed in accordance with the previous moving direction, even in a situation where tracking by a timer interrupt cannot be performed, counting processing is performed during movement, so that high-speed tracking becomes possible and resolution can be improved.

[Brief description of the drawings]

FIG. 1 is a flowchart showing a counting method of a pointing device according to the present invention, FIG. 2 is an explanatory diagram showing a counting process according to the present invention, FIG. 3 is a timing chart of a skip counting method of the present invention and counting of a conventional pointing device. FIG. 4 is a block diagram showing a configuration example of a mouse, and FIG. 5 is a flowchart showing a conventional count process for mouse output. 1 ... mouse, 2a, 2b ... rotation sensor, 3 ... button switch, 4 ... ball, 5 ... personal computer, 6 ... CPU.

Claims (1)

(57) [Claims] 1. A pointing device for outputting a moving direction and a relative moving amount as a two-phase pulse signal. When a two-phase signal is detected simultaneously and the moving direction cannot be specified, a skip count is performed according to the previous moving direction. A counting method of a pointing device, which is performed.