JPS6139711A - Computer control system - Google Patents

Abstract

PURPOSE:To control quickly and accurately a controlled system by using constants being in relation of functions so as to change each input/output ratio of plural circuits to be controlled whose input/output ratio is specified thereby changing the constants while the relation of function is kept to a microcomputer. CONSTITUTION:A computer control system 1 is so constituted that a microcomputer 3 changes constants GR, GG, GB while keeping relation of function in changing each input/output ratio of plural amplifier circuits 2r, 2g, 2b whose input/output ratio is specified respectively by the constants GR, GG, GB in relation of function mutually. The operation requiring more complicated calculation as the number of the amplifier circuits 2r, 2g, 2b as the circuits to be controlled is increased is processed at high speed by the microcomputer 3 and plural constants to be obtained in proportional (linear) and nonlinear relation are computed out accurately in a short time, then this system is suitable for a controlled system requiring quick and accurate control.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a computer control system that is capable of controlling a plurality of controlled circuits without overruling their mutual functional relationships.

l [Prior art] Color television receivers are equipped with a contrast control circuit to adjust the contrast of the image, but the three primary color images of R (red), G (green), and B (blue) are The contrast control circuit, which allows the gain to be varied for each primary color video signal, helps maintain white balance.
It is necessary to change the gain of the amplifier circuit as a controlled circuit provided for each primary color video signal with a certain relationship. [Problems to be solved by the invention] The conventional contrast control circuit described above is ,,G.

Since an amplifier circuit that controls the contrast is provided independently for each primary color video signal of B, there are problems such as difficulty in maintaining accurate white balance when the gains of the three amplifier circuits are changed simultaneously. There was a point.

[Means to solve all problems]

The present invention solves the above-mentioned problems, and includes a plurality of controlled circuits whose input/output ratios are defined by constants having a functional relationship with each other, and the input/output ratio of each of these controlled circuits. The gist of the present invention is to provide a microcomputer that performs unnecessary calculations to change the functional relationship while maintaining it, and changes the constant based on the result of the calculation. [Function] This invention provides that when changing each input/output ratio of a plurality of controlled circuits whose respective input/output ratios are defined by constants having a mutually functional relationship, the microcomputer maintains the functional relationship while Control the controlled object quickly and accurately by changing constants.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a circuit diagram showing an embodiment of the computer control system of the present invention, and FIG. 2 is a diagram showing the input/output relationship of the amplifier circuit shown in FIG. 1.

In FIG. 1, a computer control system 1 controls the gains of variable gain amplifier circuits 2r, 2g, and 2b provided for each primary color video signal of red, green, and blue as controlled circuits from a microcomputer 3. Voltage Cv□, Cvo, C
The control is performed according to VB, and the contrast of the image can be adjusted without disturbing the white balance. A launch circuit 4 and a D/A converter circuit 5 are connected between each amplifier circuit 2'r, 2g, 2b and the microcomputer 3, and each latch circuit 4 is closed by a corresponding address decoder circuit 6. An AND gate circuit 7 is connected thereto. When the AND gate circuit 7 is closed by the address decoder circuit 6, it transmits a control pulse called a write pulse from the microcomputer 3 to the latch circuit 4, and when the data is output to the data bus 9. is launched into the latch circuit 4. Microcomputer 3 and address decoder circuit 6 are connected to address bus 8, and microcomputer 3 and latch circuit 4 are connected to data bus 9.

Here, the gain of each amplifier circuit 2r, 2g, 2b is GR
+ G O + G B, the outputs YRo, YGo, Y of each amplifier circuit 2r, 2g, 2b for input XO
BO is YB□ =, ':, GRXOt YGo =
It is expressed as GGXO+YBO=QBxO, and these relationships are as shown in FIG.

In this case, as a condition to maintain white balance,
Gain GR + G G r as a constant that determines the input/output ratio
There is always a constant functional relationship between G and B, that is, GRt
It is required that the ratio GG*GB be constant.

In other words, the control voltage CvR9CvG that determines the gain GR+GG, GB of the amplifier circuit 2 ", 2g, 2b,
Regarding CVB, it is also required that the ratio of CvR9CvG and CVB be constant.

Therefore, for example, to change the gain of amplifier circuit 2g,
By changing the control voltage CvG by △CVG, CVG (=
CvG10△CVO), the other amplifier circuit 2r,
Regarding the control voltage of path 2b, for example C'VB, it is necessary to hold the control voltage of path 2b, C'VBK:1.

Therefore, the control voltage is set to △C with the green video signal as a reference.
When VG is changed, by using CVG and CVR9CvB stored as data before the change, the microcomputer 3 executes calculations based on the above calculation formula, thereby obtaining data C necessary for maintaining white balance. ′
vR,,C'VB can be obtained quickly and accurately.

Therefore, the inaccurate contrast control that conventionally relied on manual adjustment can be performed quickly and accurately by taking advantage of the high-speed arithmetic processing capability of the microcomputer 3.

In this way, the computer control system 1 includes a plurality of amplifier circuits 2r, 2 whose respective input/output ratios are defined by constants GTL, GG, and GB that have a functional relationship with each other.
When changing the input/output ratios of g and 2b, the microcomputer 3 maintains the above functional relationship while changing the constant "R+
Since the configuration is configured to change GG + GB, the microcomputer 3 can process operations that require complex calculations at high speed as the number of amplifier circuits 2r, 2g, and 2b as controlled circuits increases. Proportional relationship (l
multiple constants to be found that have a shape relationship) or a nonlinear relationship,
Since it can be accurately determined in a short time, it is suitable for controlled objects that require quick and accurate control.

〔Effect of the invention〕

As explained above, according to the present invention, when changing each input/output ratio of a plurality of controlled circuits whose respective input/output ratios are defined by constants having a mutually functional relationship, the microcomputer maintains the functional relationship. However, because the constants are changed, the microcomputer can process operations that require complex calculations at high speed as the number of controlled circuits increases. Since a plurality of constants to be determined can be determined accurately in a short period of time, it has excellent effects, such as being suitable for controlled objects that require quick and accurate control.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram showing an embodiment of the computer control system of the present invention, and FIG. 2 is a diagram showing the input/output relationship of the amplifier circuit shown in FIG. 1. 1... Computer control system, 2r, 2g, 2b
...Amplifier circuit, 3...Microcomputer, 4.
...Latch circuit, 5...DA conversion circuit, 6...Address decoder circuit, 7...AND gate circuit, 8...
・Address bus, 9...Theta pass.

Claims (1)

[Claims] A plurality of controlled circuits whose respective input/output ratios are defined by constants having a functional relationship with each other, and necessary for changing each input/output ratio of these plurality of controlled circuits while maintaining the functional relationship. A computer control system comprising a microcomputer that performs calculations and changes the constants based on the calculation results.