JP3351654B2 - Trigonometric function data conversion circuit and meter device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a trigonometric function data conversion circuit and a meter device using the same, and is used, for example, in a speedometer of an automobile and a tachometer for indicating an engine speed.

[0002]

2. Description of the Related Art Speedometers and tachometers of automobiles use a frequency data converter which receives a pulse signal having a frequency corresponding to speed information or rotation speed information, processes the pulse signal and converts it into another data. Meter output is controlled using the output of the frequency data converter.

FIG. 8 shows a conventional example of an analog pointer type speed meter device mounted on an automobile. Here, reference numeral 70 denotes an analog pointer type meter main body, and reference numeral 80 denotes an integrated circuit integrated meter control device.

FIG. 9 is a perspective view schematically showing the structure of the meter main body 70 in FIG. The analog pointer type meter main body 70 includes electromagnetic coils 71 and 72 wound corresponding to two bobbins disposed orthogonal to each other, a rotating shaft 73 provided in a direction orthogonal to these, and It has a permanent magnet 74 attached to the middle part of the rotating shaft 73 and arranged inside the bobbin, and a pointer 75 attached to the tip of the rotating shaft 73 and arranged outside the bobbin.

In the meter control device 80, a cycle counter 81 receives a pulse signal (meter control signal) having a cycle corresponding to the speed information, counts the cycle, and generates data representing a frequency amount.

The designated angle quantified data generation circuit 82 generates data (designated angle quantified data) representing a digital amount corresponding to the meter designated angle in accordance with the frequency amount of the output data of the period counter 81.

The trigonometric function data conversion circuit 83 converts the output data of the designated angle quantification data generation circuit 82 into trigonometric function data (SIN, COS), and stores a sin ROM (readout) storing the SIN function data. A dedicated memory 831 and a cos ROM 832 storing COS function data. ROM for the above sin
In some cases, a decoder that decodes input data and outputs SIN function data and COS function data may be used instead of the ROM 832 for the cos 831.

The DA conversion circuit 84 converts the output data of the trigonometric function data conversion circuit 83 into a current or a voltage by D / A conversion (or pulse width modulation; PWM).
The meter driving circuit 85 supplies a current amount corresponding to the output of the DA conversion circuit 84 to the two electromagnetic coils 71 and 72 of the meter main body 70.

FIG. 10A shows the relationship between the designated angle and the output data in the designated angle quantified data generating circuit 82, and FIG. 10B shows the relationship between the designated angle in the meter body 70 and two electromagnetic waves. The amount of current flowing through the coils 71 and 72 (S
INθ, COSθ) and the direction. The rotational angle of the permanent magnet 74 is drive-controlled in accordance with the vector sum of the magnetic fields (X, Y) generated by the electromagnetic coils 71 and 72, whereby the pointing angle of the pointer 75 is determined.

FIGS. 11A and 11B show FIG.
FIG. 3 is a block diagram illustrating a trigonometric function data conversion circuit therein and a timing diagram illustrating an operation example thereof. By the way, the above-mentioned conventional trigonometric function data conversion circuit 83 is used for sin, c
Since the ROM for os or two decoders is used, there is a problem that the cost increases.

In order to solve this problem, for example, FIG.
Focusing on the symmetry of the SIN function and the COS function in the first quadrant of the variable range of the trigonometric function from 0 to 2π radians as shown in FIG. 5, the SIN function data from 0 ° to 90 ° (π / 2) is converted to 90 °. By diverting as COS function data of up to 0 °, one R
It is conceivable that the OM is also used as a ROM for cos.

[0012] In this case, in response to an address specified by the plurality of bits of the bi <br/> Na Li data representing the variables SI
Stores the N function data, considered that to read the function data by controlling the inversion / non-inversion of the logic level of the binary Lee data address inputs in response to a read of the read or COS function data of the SIN function data Can be

[0013] However, for example, 4 bit binary 16 steps of variable specified by the address input consisting of Li data (π / 2) × N / 16 (N is 0 to 15) SIN function data and COS function data corresponding to the 45 °
It is not a target when observed around (π / 4).

That is, if the 4-bit address input is, for example, (0000) = 0 °, if the address input is not inverted when reading the SIN function data, SIN0
° data is read. On the other hand, when reading the COS function data, the address input is inverted (11).
11) = 90 ° × 15/16, and COS (90 ° ×
15/16) (not COS 90 ° data) is read out, so that a conversion error occurs in the function data corresponding to 90 ° × 1/16, which is 1 LSB of the address input.

As described above, when a conversion error of the function data occurs, a reading error of the meter occurs.
In order to use the OM as the ROM for the SIN and the ROM for the COS, it is necessary to devise a circuit.

[0016]

As described above, in the conventional trigonometric function data conversion circuit and the meter device using the same, one ROM storing the SIN function data or the COS function data is stored in the ROM for the SIN and the COS. In the case where the function data is also used, there is a problem that a conversion error of the trigonometric function data occurs if one function data is simply used as the other function data.

The present invention has been made in order to solve the above-mentioned problem. One ROM storing SIN function data or COS function data is stored in a ROM for SIN and COS.
When reading out one function data as the other function data also as the OM, a trigonometric function data conversion circuit and a meter device using the same can minimize the amount of conversion error of the function data and reduce the cost. The purpose is to provide.

[0018]

Means for Solving the Problems] trigonometric function data conversion circuit of the present invention is designated by the binary Lee data of a plurality (n) bits representing the variables in one quadrant of the variable range 0~2π radians trigonometric Corresponding to the input
A data output circuit for outputting one of the SIN function data and the COS function data which is targeted around the intermediate angle of the variable in the one quadrant; and reading the SIN function data from the data output circuit or the COS function an input inversion control circuit controls the logic level of the inversion / non-inversion of the binary Lee data input is input to the data output circuit depending on whether read data, the input function data read from the data output circuit In response to the switching control in the inversion control circuit, SIN function data or CO
A SIN / COS separation circuit for separating as S function data.

Further, by performing a predetermined amount of correction on the input at regular intervals of a read cycle of the data output circuit, the function data read out from the data output circuit a plurality of times corresponding to a certain input can be obtained. It is desirable to have an address input correction circuit that brings the average value closer to the function data read out corresponding to the theoretical angle.

[0020]

[Action] When using as a data output circuit, for example ROM is designated address by binary Lee data, in correspondence of one said quadrant between an address and SIN function data and the correspondence relationship and address and COS function data One of the SIN function data and the COS function data that are targeted around the intermediate angle of the variable is stored, and the function data is output according to the designated address.

In this case, the variable range 9 of the SIN function or COS function specified by the n-bit address input
For each angle at which 0 ° is divided into 2 ⁿ , 最小 of the minimum angle divided
One ROM storing the SIN function data or the COS function data corresponding to the angle obtained by adding the amount of SIN is also used as the ROM for the SIN and the ROM for the COS, and by performing the inversion control of the address input, one function data is converted to the other. By reading as function data, address input and S
Correspondence with IN function data and address input and CO
Almost accurate function data can be read such that the correspondence with the S function data is targeted around the middle angle of the variable. In addition, the circuit configuration required for this is simple, and the cost can be reduced. Further, by adding the address input correction circuit, the generation amount of the conversion error of the function data can be suppressed as much as possible.

[0022]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 shows a first embodiment of a trigonometric function data conversion circuit according to the present invention. This trigonometric function data conversion circuit includes an address input inversion control circuit 20 and one ROM.
30 and a SIN / COS separation circuit 40.

The ROM 30 stores a variable range 0 of the trigonometric function.
(In this example the first quadrant) one quadrant of ~2π radians plurality representing the variables in (n) of the bit binary
In response to an address specified by chromatography data is stored one of SIN function data and COS function data, and outputs the function data in accordance with the specified address.

In this case, as shown in FIG. 2, the ROM 30 stores the correspondence between the address (variable) and the SIN function data and the correspondence between the address and the COS function data at the intermediate angle of the variable (45 ° in this example). ) stores almost exact function data such that the subject around the.

That is, when storing the SIN function data, SIN ｛90 ° × (N / 2 ⁿ ) + 90 ° × (1
/ 2 ⁿ ) × (1/2)}, and when storing COS function data, COS
｛90 ° × (N / 2 ⁿ ) + 90 ° × (1/2 ⁿ ) × (1 /
2) Store data proportional to｝.

Here, the storage data when n = 4 is: SIN {90 ° × N / 2 ⁿ + 90 ° × (1/2 ⁿ ) × (1/2)} = SIN {90 ° × N / 16 + 45 ° / 16｝ (1) COS {90 ° × N / 2 ⁿ + 90 ° × (１ ／ ⁿ ) × (1/2)} = COS {90 ° × N / 16 + 45 ° / 16｝} 2) That is, the function data shown in FIG. 2 is obtained by dividing the variable range 90 ° of the SIN function or COS function designated by n-bit address input into 2 ⁿ divided angles.
Divided minimum angle (angle of 1 LSB of address input = 90
SI corresponding to the angle obtained by adding 1/2 of ° / 2 ⁿ )
This is N function data or COS function data.

As a result, SIN {90 ° × N / 16 + 45 ° / 16} = COS {90 ° × (15−N) / 16 + 45 ° / 16}.

In this embodiment, it is assumed that the ROM 30 stores SIN function data. The ROM 3
Instead of 0, it is also possible to use another storage means or a decoder that decodes input data and outputs the above-described SIN function data and COS function data.

[0029] The address input inversion control circuit 20, the ROM30 in the stored function data of the logical level of the binary Lee data address inputs depending on whether read as either COS function data read out as SIN function data inversion / non-inversion Is controlled.

As a specific example of the address input inversion control circuit 20, as shown in FIG. 3, an address input is input to one input terminal of each of a group of exclusive OR gate circuits 21.
A switching control signal c / s for specifying whether to read as IN function data or to read as COS function data is input to the other input terminal of each of the exclusive OR gate circuits 21 and each of the exclusive OR gate circuits 21 is Output the R
It is configured to input to the OM 30.

The SIN / COS separation circuit 40 stores the ROM 3 in response to the switching control by the switching control signal c / s.
The function data read from 0 is separated as SIN function data or COS function data, and is controlled by the switching control signal c / s.

The address input inversion control circuit 20
The SIN / COS separation circuit 40 may be formed on the same chip as the ROM 30 or on a separate chip. FIG. 4 shows the timing of an operation example of each unit in the trigonometric function data conversion circuit of FIG.

According to the trigonometric function data conversion circuit of the first embodiment, S designated by an n-bit address input
One R that stores SIN function data corresponding to an angle obtained by adding 1/2 of the minimum angle obtained by dividing the variable range 90 ° of the IN function or COS function by 2n into 2n.
The OM 30 is also used as the ROM for the SIN and the ROM for the COS, and the inversion control of the address input is performed to read out one function data as the other function data. Almost accurate function data can be read such that the correspondence with the COS function data is targeted around the intermediate angle 45 ° of the variable. In addition, the circuit configuration required for this is simple, and the cost can be reduced.

When the function data shown in FIG. 2 is read from the ROM 30, the correspondence between the address input (horizontal axis) and the function data (vertical axis) is based on the theoretical value of the SIN function variable or the COS function variable. Address input 1 for the corner
Only one half of the LSB, that is, 90 ° × (1/2 ⁿ ) ×
A conversion error is included due to being shifted (added) by (1/2). The second to solve this point
Examples are shown below.

FIG. 5A shows a second embodiment of the trigonometric function data conversion circuit of the present invention. This trigonometric function data conversion circuit is different in that an address input correction circuit 10 is added to the input side of the trigonometric function data conversion circuit of the first embodiment in order to correct the conversion error. The same reference numerals are given.

The address input correction circuit 10 includes a ROM
When the function data is repeatedly read from the address 30, a predetermined amount of correction is performed on the address input at regular intervals (every two cycles) of the read cycle (in this example, 90 ° / 2 ⁿ is added). R corresponding to a certain address input
The average value of the function data read multiple times from the OM 30 is approximated to the function data read from the ROM 30 corresponding to the theoretical angle.

That is, even if the function data read in a certain read cycle contains a conversion error corresponding to a shift of 90 ° × (１ ／ ⁿ ) × (１ ／), the function data read in the next read cycle is read. The output function data includes a conversion error corresponding to a shift of 90 ° / ²ⁿ .

Thus, if the processing for taking the average value of the function data read corresponding to each of the two address inputs (for example, the processing of integrating the read function data after DA) is performed, It can be considered that the conversion error almost disappears.

As a specific example of the address input correction circuit 10, an address input is input to one input terminal A of the adder circuit 11, and is alternately set to 0 or -1 every read cycle.
Is input to the other input terminal B of the adder circuit 11, and the output D (= D0 to D3) of the adder circuit 11 is input to each one input terminal of the exclusive OR gate circuit 21 group. I have. The address input correction circuit 10
May be formed on the same chip as the address input inversion control circuit 20 or on a separate chip.

FIG. 5B shows an operation example of each unit in the trigonometric function data conversion circuit of FIG. 5A. Also in the trigonometric function data conversion circuit of the second embodiment, similarly to the trigonometric function data conversion circuit of the first embodiment, the SIN function or the CIN function specified by the n-bit address input is used.
For each angle obtained by dividing the variable range 90 ° of the OS function by 2n, S corresponding to the angle obtained by adding 量 of the minimum angle obtained by the division
1 that stores IN function data or COS function data
One ROM is also used as the ROM 30 for the SIN and the COS, and the inversion control of the address input is performed to read out one function data as the other function data, so that the correspondence between the address input and the SIN function data and the address input are performed. It is possible to read out almost accurate function data such that the correspondence between the COS function data and the COS function data is targeted around the intermediate angle 45 ° of the variable. In addition, since the address input correction circuit 10 is added, the generation amount of the conversion error of the function data can be suppressed as much as possible.

FIG. 6 shows an address input before correction (theoretical input angle), an address input after correction (actual input angle θ), and S in the trigonometric function data conversion circuit of the second embodiment.
IN function data, COS function data, θt = tan
^The result of verifying the correspondence between ^-1 (SINθ / COSθ) and the conversion error (θt−θ) is shown.

Further, in each of the above embodiments, for example, 8
Of the bit address input, the upper two bits are quadrant designating data for designating one quadrant of the variable range of the SIN function or COS function, and the remaining lower bits designate variables in the one quadrant. If the data is data to be processed, a polarity processing circuit for processing the polarity (+-) of the function data read from the ROM according to the quadrant designation data is added to the output side of the SIN / COS separation circuit. It is possible to

That is, when the first quadrant is designated, processing is performed with the polarity of the function data read from the ROM set to +. When the second quadrant is designated, the polarity of the data read from the ROM as the SIN function data is processed as +, and the polarity of the data read as the COS function data is processed as-. . If the third quadrant is designated, the polarity data of the function data read from the ROM is processed as-. If the fourth quadrant is designated, the ROM
The polarity of the data read as the IN function data is processed as-, and the polarity of the data read as the COS function data is processed as +.

The polarity processing circuit can digitally process the function data read from the ROM. It is also possible to perform the processing indirectly, for example, by controlling the polarity of the applied voltage. Alternatively, a decoder may output a trigonometric function instead of the ROM.

FIG. 7A shows a block configuration of an example of a meter device in which the trigonometric function data conversion circuit of the present invention is applied to a vehicle speedometer or tachometer.
In FIG. 7A, an analog pointer type meter main body 70 is shown.
Are 2 arranged orthogonally as shown in FIG.
The pointing angle of the pointer is determined according to the vector sum of the magnetic fields generated by the currents flowing through the two electromagnetic coils.

The digital data processing circuit 76 receives a pulse signal having a cycle corresponding to the information to be indicated by the meter, and converts the pulse signal into binary data having a meter indicating angle corresponding to the cycle of the pulse signal. .

In the digital data processing circuit 76, the cycle counter 81 receives a pulse signal (meter control signal) having a cycle corresponding to the speed information, counts the cycle, and generates data representing a frequency amount. The indicated angle quantified data generation circuit 82 generates data (indicated angle quantified data) representing a digital amount corresponding to the meter indicated angle in accordance with the frequency amount of the output data of the period counter 81.

The trigonometric function data conversion circuit 77 has an SIN for designating the pointing angle of the pointer according to the binary data obtained by the digital data processing circuit 76,
The data is converted into COS trigonometric function data, and FIG.
It has the configuration of the embodiment described above with reference to FIG.

DA conversion circuit (or PWM circuit) 84
Is the SI output from the trigonometric function data conversion circuit 77.
The N function data and the COS function data are converted into current or voltage by D / A conversion (or PWM).

The meter drive circuit 85 outputs a current amount corresponding to the output of the DA conversion circuit (or PWM circuit) 84 (that is, a current amount corresponding to the SIN function data and the COS function data) to the meter main body 70. To the two electromagnetic coils 71 and 72.

FIG. 7B shows a block configuration of an example of a meter device in which the trigonometric function data conversion circuit of the present invention is applied to a vehicle-mounted fuel meter or temperature meter. FIG.
7B is different from the meter device shown in FIG. 7A in that an analog data processing circuit 78 is used instead of the digital data processing circuit 76, and the other components are the same. Therefore, the same reference numerals as those in FIG. The analog data processing circuit 78 receives an analog signal having a level corresponding to the information to be indicated by the meter and converts the analog signal into binary data having a meter indicating angle corresponding to the level of the analog signal.

It is needless to say that the present invention is not limited to the above-described embodiment, but can be variously modified. For example, there is a meter body using a stepping motor, and the meter body using the stepping motor can be controlled by the same control method as described above.

[0053]

As described above, according to the trigonometric function data conversion circuit of the present invention and the meter device using the same, the SI
When one ROM storing the N function data or the COS function data is also used as the ROM for the SIN and the ROM for the COS and one function data is read as the other function data, the cost can be reduced with a simple circuit configuration and the function can be reduced. The amount of data conversion errors can be minimized.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of a trigonometric function data conversion circuit according to the present invention.

FIG. 2 is a view for explaining the correspondence between an address input to a ROM in FIG. 1 and SIN function data and the correspondence between an address and COS function data;

FIG. 3 is a circuit diagram showing a specific example of an address input inversion control circuit in FIG. 1;

FIG. 4 is a timing chart showing an operation example of each unit in the trigonometric function data conversion circuit of FIG. 1;

FIG. 5 is a block diagram showing a second embodiment of the trigonometric function data conversion circuit of the present invention and a timing chart showing an operation example of each unit.

FIG. 6 is a diagram showing a result of verifying a conversion error in the trigonometric function data conversion circuit of FIG. 5;

FIG. 7 is a block diagram showing different examples of a meter device according to an application example of the trigonometric function data conversion circuit of the present invention.

FIG. 8 is a block diagram showing a conventional example of an analog pointer type speed meter device mounted on a vehicle.

FIG. 9 is a perspective view schematically showing a structure of a meter main body in FIG. 8;

10 is a characteristic diagram showing the relationship between the designated angle and the output data in the designated angle quantification data generation circuit in FIG. 8, and the relationship between the designated angle in the meter main body in FIG. 8 and the amount of current flowing through the electromagnetic coil and the direction;

11 is a block diagram showing a trigonometric function data conversion circuit in FIG. 8 and a timing chart showing an operation example thereof.

FIG. 12 shows a modified example of the trigonometric function data conversion circuit shown in FIG.
Function and C when shared as ROM
FIG. 4 is a diagram shown to explain the symmetry of an OS function.

[Explanation of symbols]

10 ... Address input correction circuit, 11 ... Addition circuit, 20 ...
Address input inversion control circuit, 30 ... ROM, 40 ... SI
N / COS separation circuit, 70: analog pointer type meter main body, 71, 72: electromagnetic coil, 73: rotating shaft, 74: permanent magnet, 75: pointer, 76: digital data processing circuit,
77: Trigonometric function data conversion circuit, 78: Analog data processing circuit, 81: Period counter, 82: Designated angle quantified data generation circuit, 85: Meter driving circuit

Continuation of front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G01P 3/489 G01D 5/20

Claims (9)

(57) [Claims] 1. A corresponding to input specified by the binary Lee data of a plurality (n) bits representing the variables in one quadrant of the variable range 0~2π radians trigonometric function, the variables in the one quadrant A data output circuit that outputs one of the SIN function data and the COS function data that are targeted around the intermediate angle, and whether the SIN function data or the COS function data is read from the data output circuit. an input inversion control circuit for input to the data output circuit by controlling the inversion / non-inversion of the logic level of the binary Lee data <br/> data input, the input inversion control function data read out from the data output circuit SI separated as SIN function data or COS function data in response to switching control in a circuit
A trigonometric function data conversion circuit, comprising: an N · COS separation circuit. 2. A trigonometric function data conversion circuit according to claim 1, wherein the data output circuit, of the SIN function data and COS function data in response to an address specified by the binary Lee data <br/> data As one of them, the correspondence between the address and the SIN function data and the address and C
A read-only memory (ROM) that stores function data in which the correspondence with the OS function data is targeted around the middle angle of the variable in the one quadrant, and outputs the function data according to a designated address. ) Or a decoder. 3. The trigonometric function data conversion circuit according to claim 2, wherein the function data stored in the ROM is:
For each angle obtained by dividing the variable range 90 ° of the SIN function or COS function designated by the n-bit address into 2 ⁿ , the function data corresponds to an angle obtained by adding 1/2 of the minimum angle obtained by the division. Characteristic trigonometric function data conversion circuit. 4. The trigonometric function data conversion circuit according to claim 2, wherein said ROM stores SIN ｛90 ° × (N / 2 ⁿ ) + 90 ° × (1/2 ⁿ ) corresponding to an address N.
A trigonometric function data conversion circuit storing SIN function data proportional to × (１ ／)｝. 5. The trigonometric function data conversion circuit according to claim 2, further comprising: performing a predetermined amount of correction on an address input at predetermined intervals of a read cycle of the ROM. A triangle comprising an address input correction circuit for making an average value of function data read from the ROM a plurality of times corresponding to a certain address input closer to function data read from the ROM corresponding to a theoretical angle. Function data conversion circuit. 6. A trigonometric function data conversion circuit according to claim 5, wherein said address input correction circuit, when reading repeatedly function data from the ROM, and to the address input for each two cycles of the read cycle 90 ° / 2 ⁿ
And a trigonometric function data conversion circuit. 7. A trigonometric function data conversion circuit according to any one of claims 2 to 6 1, upper 2 bits of the binary Lee data of a plurality of bits that specify the address is S
Quadrant designating data for designating one of the four quadrants that are the variable range of the IN function or COS function, and the remaining lower bits are data for designating a variable in the one quadrant. A trigonometric function data conversion circuit for processing the polarity of the function data read from the ROM according to the quadrant designating data. 8. An analog pointer-type meter main body configured such that a pointing angle of a pointer is determined by a magnetic field generated by a current flowing through two electromagnetic coils and a magnetic field of a permanent magnet on the pointer axis, and a meter pointing object. A digital data processing circuit for receiving a pulse signal having a cycle corresponding to the information to be converted into binary data having a meter indicating angle corresponding to the cycle of the pulse signal; and a triangular function variable range of 0 to 2π radians. out in response to input specified by the binary Lee <br/> data of a plurality (n) bits representing the variables in one quadrant of, such that the subject around the middle angle variables in said one quadrant A data output circuit for outputting one of the SIN function data and the COS function data; and a plurality of data read out corresponding to a certain input from the data output circuit. An input correction circuit provided to approximate the average value of the numerical data to the function data read corresponding to the theoretical angle, and performing a predetermined amount of correction on binary data input from the digital data processing circuit; and an input inversion control circuit for input to the data output circuit by controlling the inversion / non-inversion of the logic level of the binary Lee data <br/> data input depending on whether read or COS function data read out SIN function data from the circuit An SI for separating function data read from the data output circuit as SIN function data or COS function data in accordance with the switching control in the input inversion control circuit;
An N · COS separation circuit; and a meter driving circuit that supplies a current amount corresponding to the SIN function data and the COS function data output from the SIN / COS separation circuit to two electromagnetic coils of the meter main body. Meter device. 9. An analog pointer-type meter main body configured such that a pointing angle of a pointer is determined by a magnetic field generated by a current flowing through two electromagnetic coils and a magnetic field of a permanent magnet on the pointer axis, and a meter pointing object. An analog data processing circuit for inputting an analog signal having a level corresponding to the information to be converted into binary data having a meter indicating angle according to the level of the analog signal; and a triangular function variable range of 0 to 2π radians. out in response to input specified by the binary Lee <br/> data of a plurality (n) bits representing the variables in one quadrant of, such that the subject around the middle angle variables in said one quadrant A data output circuit that outputs one of the SIN function data and the COS function data; and a plurality of readings corresponding to a certain input from the data output circuit. An input correction circuit provided to approximate the average value of the performed function data to the function data read corresponding to the theoretical angle, and performing a predetermined amount of correction on binary data input from the analog data processing circuit; input inversion control by controlling the inversion / non-inversion of the logic level of the binary Lee data <br/> data input is input to the data output circuit according the data output circuit to read or whether COS function data read out SIN function data A circuit for separating the function data read from the data output circuit into SIN function data or COS function data in accordance with the switching control in the input inversion control circuit;
An N · COS separation circuit; and a meter driving circuit that supplies a current amount corresponding to the SIN function data and the COS function data input from the SIN / COS separation circuit to two electromagnetic coils of the meter main body. Meter device.