JPH0687066B2 - Endless volume output capture device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention is used for a readout oscilloscope and the like. The present invention relates to an output capturing device for an endless volume.

(Prior Art) As shown in FIG. 5, in a conventional volume output capturing device, a controller 21 receiving an output from a microcomputer 20 supplies digital data to a D / A converter 22.
A potentiometer is configured by the variable resistor 23, and the output voltage from the potentiometer and the analog voltage output from the D / A converter 22 are supplied to the comparator 24 for comparison, and the output of the comparator 24 is the input port 25. It is supplied to the microcomputer 20 via.

The microcomputer 20 sequentially changes the digital data supplied to the D / A converter 22 by the controller 21, detects that the output of the comparator 22 changes from high potential to low potential, and the output of the comparator 24 becomes high. The slider position of the variable resistor 23 was detected by the input digital data to the D / A converter when the potential changed to the low potential.

(Problems to be Solved by the Invention) According to the conventional device as described above, the variable resistor can be applied to a multi-rotation type, but when the variable resistor is an endless type, the rotation of the slider is different. This is a multi-valued function in which the same output voltage is generated at the position, and there is a problem that the rotational position of the slider does not correspond to the output voltage on a one-to-one basis.

Further, when the output voltage of the potentiometer is set to the output voltage between adjacent bits, when noise or the like exists, the digital data converted from the output voltage of the potentiometer fluctuates as g and h as shown in FIG. , Becomes unstable digital data. As a result, when the output voltage of the potentiometer is displayed as a digital value with digital data, there is a problem that the display fluctuates.

Therefore, when the cursor is used in the readout oscilloscope, the display fluctuates and accurate measurement cannot be performed.

It is an object of the present invention to provide an endless volume output capturing device capable of capturing the output of an endless volume.

(Means for Solving the Problems) The present invention has the following constitution in order to solve the above problems.

The present invention provides an endless volume output capturing device, an endless volume, a first analog switch that receives an output from the endless volume as an input and passes the output for a predetermined period, and a first analog switch that receives an output of a D / A converter as an input. A second analog switch that allows the output of the D / A converter to pass while the input does not pass, a first storage unit that stores data for detecting the slider position of the endless volume, and a slide of the endless volume. Second storage means for storing output data for detecting the pendulum position, and data stored in the first storage means for a period during which the first analog switch passes the output from the endless volume and converted into an analog signal.
The output voltage level of the D / A converter is compared with the output level of the endless volume selected by the first analog switch, and the slider position of the endless volume is substantially detected in cooperation with the first storage means. A comparator and a voltage holding circuit that holds the output voltage of the D / A converter that receives the data stored in the second storage means and converts it into an analog signal while the second analog switch is passing the input,
It is based on the output of the comparator that the input pass periods of the first and second analog switches are controlled, and that the slider position of the endless volume has changed by more than a predetermined amount based on the data of the first storage means. And a control means for changing the stored data of the second storage means by a predetermined value when the determination is made.

(Operation) In the output capturing device of the endless volume of the present invention, the output voltage of the endless volume via the first analog switch and the analog voltage obtained by converting the data stored in the first storage means by the D / A converter are comparators. And it is detected by the output of the comparator that the slider position of the endless volume has changed, and it has been detected that the slider position of the endless volume has changed by more than a predetermined amount, the second storage means. The stored content of is changed by a predetermined value. The stored content of the second storage means, which has been changed by a predetermined value, is converted into an analog voltage by the D / A converter, supplied to the voltage holding circuit, and held by the voltage holding circuit.

Therefore, when the slider position of the endless volume is changed by a predetermined amount, the output voltage of the voltage holding circuit is changed by the voltage corresponding to the predetermined value. However, unless the slider position of the endless volume is moved beyond the predetermined amount, the output voltage of the voltage holding circuit cannot be changed by the voltage corresponding to the predetermined value. When the value is changed by a value less than, it does not affect the output voltage of the voltage holding circuit and is equivalent to having a hysteresis.

Moreover, since neither the first analog switch nor the second analog switch is turned on, only one D / A converter is required.

(Examples) Hereinafter, the present invention will be described with reference to Examples.

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention, and FIG. 2 is a schematic diagram showing the configuration of an endless volume used in an embodiment of the present invention.

As shown in the schematic perspective view of FIG. 2 (a) and the schematic front view of FIG. 2 (b), the endless volume has a rotating shaft 10 of the sliders 11 and 12 in common and a partially open circumference. The resistors 13 and 14 formed along the structure are provided such that the positions of the open portions are displaced by 180 degrees. Here, the slider 11 slides on the resistor 13, and the slider 12 slides on the resistor 14. Now, suppose that the output from the resistor 13 is called an A-phase output and the output from the resistor 14 is called a B-phase output. A voltage is applied to both of the resistors 13 and the same voltage is applied to both ends of the resistor 14 to be used as a potentiometer. Therefore, the output from the slider 11 is the third
The output from the slider 12 is as shown in (a-2) of FIG. 3 (a), as shown in (a-1) of FIG. It has a phase difference. In Fig. 3 (a), "D" corresponds to the length of the open portion of the resistor 14 (13), and the arrow "e" shows the change in output voltage when the rotary shaft 10 is rotated counterclockwise. Direction, arrow “b” is axis of rotation 10
Shows the changing direction of the output voltage when the is rotated clockwise, and the arrows "a" to "d" are for explaining the switching position between the A-phase voltage and the B-phase voltage.

3 (b) is an enlarged view of a part of FIG. 3 (a). In FIG. 3 (b), "E" indicates the rotary shaft 10.
"F" indicates the allowance when rotating clockwise, and "F" indicates the allowance when reacting clockwise rotation of the rotating shaft 10. If there are no allowances "E" and "F", the rotating shaft moves faster. This is because it may interfere with the phase switching when turned. Also,
Each number shown in FIG. 3 (b) is a decimal number indicating a digital value input to a D / A converter (assuming 12 bits) described later.

Further, as shown in FIG. 2 (c), the rotary shafts of the sliders 11A and 12A are different from the endless volume shown in FIG. 2 (a).
10A is common, the slider 11A and the slider 12 are provided at an angle of 180 degrees, and the resistor 13A is formed along a partially open circumference.
The same applies to an endless volume provided with 14A and 14A so that the opening position is in the first direction. Here slider 11
A slides on the resistor 13A, and the slider 12A slides on the resistor 14A.

In this embodiment, the controller 21A which receives the output from the microcomputer 20A supplies digital data to the D / A converter 22. The analog voltage converted by the D / A converter 22 and the output voltage from the endless volume output via the analog switch 26 are compared by the comparator 24, and the output of the comparator 24 is input via the input port 25. Supply to the microcomputer 20A.

Microcomputer 20A is D / A by controller 21A
A change in the output of the comparator 24 is detected by changing the digital data supplied to the converter 22. Outputs of endless volume J, K, L, M are supplied to the analog switch 26, and the analog switch 26 is switched and controlled by the output from the microcomputer 20A via the controller 21A. J,
The output of K, L, M is switched and output. Further, the output from the microcomputer 20A controls the switching of the analog switch 27 via the controller 21A, and the analog voltage converted by the D / A converter 22 is selected by the voltage holding circuits 28, 29,
Supply to 30 or 31. Here, the voltage holding circuit 28 is an endless volume J, the voltage holding circuit 29 is an endless volume K, and the voltage holding circuit 30 is an endless volume L.
In addition, the voltage holding circuit 31 is made to correspond to the endless volume M, and the voltage holding circuits 28 to 31 are D / A converters 22.
Holds the analog voltage converted by.

Here, the microcomputer 20A supplies the switching signals of the analog switches 26 and 27 and the D / A via the controller 21A.
When the converted digital data of the converter 22 is supplied and the digital data corresponding to the comparison voltage of the comparator 24 is supplied to the D / A converter 22, the output voltage of the endless volume changes from the change in the output of the comparator 24. Has been detected.

The analog switch 26 is switched by the output of the microcomputer 20A via the controller 21A, and when the rotary shaft of the endless volume is rotated, the fact that the rotary shaft is rotated is detected by the microcomputer 20A by a change in the output of the comparator 24. The microcomputer 20A is D /
Different digital data is supplied to the A converter 22. On the other hand, D
When the digital data output to the / A converter 22 is for the holding voltage of the voltage holding circuits 28 to 31, all the endless volumes J to M by the analog switch 26 are output.
Do not make a selection.

Therefore, the D / A converter 22 determines the output voltage from the endless volume, that is, the voltage depending on the rotation amount of the rotation shaft of the endless volume and the rotation amount of the rotation shaft of the endless volume. It is switched in a time division manner when it is supplied to.

Hereinafter, the D / A converter 22 will be described as a 12-bit D / A converter.

Next, the operation of this embodiment will be described with reference to FIG.

When the power is turned on, in synchronization with the switching of the analog switch 27 to set the voltages in the voltage holding circuits 28 to 31, respectively,
The digital data corresponding to each D / A converter 22 is supplied. As a result, the voltage holding circuit 28 to 31 is set to a voltage immediately before the time of the voltage cut-off before the initial voltage or voltage is turned on (step S _1). Step S ₁ followed by analog switch
The output of the switching signal to 27 is prohibited (step S ₂ ). The holding voltage of the voltage holding circuits 28 to 31 is maintained by performing step S ₂ .

Following step S ₂ , a switching signal is supplied to the analog switch 26 to select one of the endless volumes J to M (step S ₃ ). The current position of the subsequently slider selected endless volumes step S ₃ is checked (step S _4). Step S ₄ is as shown in FIG. 4 (b).

The check of the current position of the slider of the endless volume will be described.

First, the output voltage from the endless volume is "50" of A phase.
～4050 "there between is checked (step S _41).
Here, "50", "4050", etc. are 10 bits of 12-bit digital data.
The values are shown in decimal notation, the input digital data to the D / A converter 22 is the same as the values in decimal notation, and so on. In step S ₄₁ , when the output voltage from the endless volume is between “50-4050” of one phase,
Following step S ₄₁ , it is checked whether or not there is a value higher than the center value “2050” (step S ₄₂ ). If it is determined to be a high value in step S _42, the current position is sequentially detected with reference to the next center value (step S ₄₃ ). For example, the center value is set to "3050" and it is checked whether it is higher than this, and when it is high, the center value is set to "3550" and it is checked whether it is higher than this. In addition, the center value "30
50 is checked whether higher than this "is the center value when:" the 2550 ". Detects the output voltage of the endless volume in the same manner. The output voltage of the detected endless volumes in step S ₄₃ is The microcomputer 20 is a digital data value applied to the D / A converter 22.
It is stored in the current position memory of A (step _S44 ).

In step _S42 , when the center value is "2050" or less, the center value is set to "1050" and it is checked whether it is higher, and when it is higher, the center value is set to "1550" and it is checked whether it is higher than this. , And the center value is "1050"
In the following cases, the center value is set to "550" and it is checked whether it is higher than this. In the same manner, the output voltage of the endless volume is detected (step _S45 ), and then step _S44 is executed.

If not between A-phase "50-4050" in step S _41, B
During the phase, the output voltage of the endless volume is detected as in steps S _{41 to} S ₄₃ and step S ₄₅ (steps
_S46 ) and then step _S44 are executed.

If there is no interrupt following step S ₄ , it is checked that the slider position of the endless volume has moved from the previous slider position (step S ₅ ), and if it is determined not to move, Digital data for the voltage holding circuit is set in the D / A converter 22 as shown in step S ₉ described later.

If it is judged to have moved in step S ₅ has stored contents of the data memory for the voltage holding circuit is changed (step
S ₆ ), then it is checked whether the slider position of the endless volume is within the valid range (step S ₇ ), and if it is determined that it is within the valid range, step S ₉ described later is executed. When it is determined that the effective range in step S ₇ is the output voltage of the endless volume is switched and the A-phase and B-phase (step S _8), then step S ₄ is executed.

When an interrupt occurs, the voltage holding circuit data is set in the voltage holding circuit data memory (step
S ₉ ), then the data for the voltage holding circuit that was set is D / A
Is output to the converter 22 (step S _10), is converted to an analog voltage, is supplied to the voltage holding circuit selected via the analog switch 27.

Here, the step S ₅ to S ₉ will be described in detail. (4th
Once the execution of FIG. (C) ~ (e) refer) Step S _5, transfers the stored contents of the current position memory (see step S ₄₄₎ which stores the slider position of the endless volume digital data in the register Then, "+30" is added to the registered value in the register (step S
₅₁ ), the stored contents of the register are supplied to the D / A converter 22 (step _S52 ), and the converted analog voltage is compared with the output voltage from the endless volume selected by the analog switch 26 by the comparator 24. (Step
S ₅₃ ). As a result of the comparison in step S ₅₃ , when the output voltage from the endless volume is larger than the converted analog voltage of the D / A converter 22, that is, when it is determined that the slider moves by “+30” or more, step S _{53 60} is executed (step S ₅₄ ). If it is determined in step _S54 that the slider has moved less than "+30", the stored contents of the current position memory are transferred to the register and "-30" is added to the value registered in the register (step _S55 ), The stored contents of the register are supplied to the D / A converter 22 (step S ₅₆ ), and the converted analog voltage is compared with the output voltage from the endless volume selected by the analog switch 26 by the comparator 24 ( Step _S57 ).

Step S ₅₇ compares the result of the former is smaller than the latter, i.e. the slider is when it is determined to be moving "-30" or more is performed step S ₇₀ (step S
₅₈ ).

Step slider in S ₅₈ is "-30" when it is determined that movement of less than the slider is Step S ₉ and is executed considered is not moving, the stored contents of the memory for the voltage holding circuit changes The data stored in the voltage holding circuit data memory is
Is supplied to A converter 22 is converted into an analog voltage (step S _10). The converted analog output voltage of the D / A converter 22 converted in step S ₁₀ is applied to the voltage holding circuit selected by the analog switch 27. In this case even if the slider endless volume is deemed not to be moved in step S _58, because the stored contents of the data memory for the voltage holding circuit has not changed, the holding voltage of the voltage holding circuit There is no change.

When step S ₆₀ following step S ₅₄ is executed,
“+30” is added to the contents stored in the current position memory (step S
₆₀ ). Following step S ₆₀ is +1 in the storage content of the data memory for voltage holding circuit (step S _61). Step S
Following ₆₁ , the slider position of the endless volume is "405
0 "or whether is checked (step S _63)," 4050 "
If it is determined that the above is not the case, step S ₉ is executed. The stored contents of the data memory for the voltage holding circuit are supplied to the D / A converter 22 and converted into an analog voltage. This converted analog voltage is passed through the analog switch 27,
It is applied to the voltage holding circuit selected by the analog switch 27. Therefore, the output voltage of the voltage holding circuit is changed by the amount "+1" stored in the data memory for the voltage holding circuit.

When slider position of the endless volume is determined to more than "4050" in step S _63, following the step S _63, step S ₈ is executed, then the step S ₄ is executed.

Further, when step S ₇₀ is executed subsequent to step S ₅₈ , as in steps S ₆₀ , S ₆₁ and S ₆₃ , steps S ₇₀ , S ₇₁ and S
₇₃ is executed. In Step S ₇₀ in place of the "+30" in the step S ₆₀ is "+30", in step S ₇₁ in place of the "+1" in step S ₆₀ is "-1", the step S in step S _{73 63} in place of the "4050""50" are used, respectively, but act similar to step S _60, S _61, S _63,
The explanation is omitted because it is easily analogized.

In the above description, since the output voltage of the endless volume, that is, the slider of the endless volume is changed when changed by “30”, it is equivalent to digitally providing hysteresis, and prevents malfunction due to noise or the like. Furthermore, "30" may be set to another value.

Further, as described with reference to FIG. 3 (b), since a margin is provided for the rotation angle of the rotary shaft of the endless volume, it is possible to switch to the other phase before the output voltage of one phase is saturated. In this case, with one endless volume "about
The output voltage of the voltage holding circuit can be changed in 200 ([3000/30] x 2) steps.

(Effect of the Invention) As described above, according to the present invention, when it is detected that the slider position of the endless volume has changed by more than a predetermined amount, the content stored in the second storage means is changed by a predetermined value, so that the endless volume is changed. When the sliding position of the volume is changed by a predetermined amount, the output voltage of the voltage holding circuit is changed by a voltage corresponding to another predetermined value.

As a result, unless the slider position of the endless volume is moved by a predetermined amount, the output voltage of the voltage holding circuit cannot be changed by the voltage corresponding to the predetermined amount. When the change is less than the fixed amount, the output voltage of the voltage holding circuit is not changed and it is equivalent to having hysterin.

Also, since the first analog switch and the second analog switch are not controlled to be in the ON state at the same time, only one D / A converter is required.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention. 2 (a), (b), and (c) are schematic diagrams showing the configuration of an endless volume used in an embodiment of the present invention. FIG. 3 is a characteristic diagram of the rotation angle of the rotary shaft of the endless volume versus output voltage. FIG. 4 is a flow chart for explaining the operation of one embodiment of the present invention. FIG. 5 is a block diagram showing a conventional configuration. FIG. 6 is an explanatory view showing the operation of the conventional example. 20A ... Microcomputer, 21A ... Controller,
22 …… D / A converter, 24 …… comparator, 25 …… input port, 2
6 and 27 …… Analog switch, 28 to 31 …… Voltage holding circuit.

Claims (1)

[Claims] 1. An endless volume, a first analog switch that receives an output from the endless volume as an input and passes it for a predetermined period, and a first analog switch that receives an output of a D / A converter as an input and passes the input. A second analog switch that allows the output of the D / A converter to pass through during a non-existing period, and a first storage means that stores data for detecting the slider position of the endless volume,
The second storage means for storing the slider position detection output data of the endless volume and the analog signal in response to the data stored in the first storage means while the first analog switch is passing the output from the endless volume The output voltage level of the D / A converter converted into the output level of the endless volume selected by the first analog switch is compared, and the slider position of the endless volume is substantially determined in cooperation with the first storage means. And a voltage holding circuit that holds the output voltage of the D / A converter that receives the data stored in the second storage means during the period in which the second analog switch passes the input and converts the data into an analog signal. The circuit and the first and second analog switches control the input passage period, and based on the data of the first storage means, Second when Doko position is determined based on the output of the comparator that it has changed by more than a predetermined amount
An output capturing device for an endless volume, comprising: a control unit that changes a storage data of a storage unit by a predetermined value.