JPS60220614A - Device for changing smoothly digital quantity - Google Patents

Abstract

PURPOSE:To eliminate influences of a converter which obtains a reciprocal of a variation, by providing a latch circuit, where the output of an adder is held temporarily, and the adder, which outputs a carry output, instead of the converter and a frequency divider. CONSTITUTION:When a variation (c) is set to a register 2 from a computer 1, an adder 7 adds an absolute volue (d) of the variation and the output of a latch 8. The latch 8 holds an output (j) of the adder 7 and updates data by a clock (g). When the value of the adder 7 exceeds the maximum value, the adder 7 outputs a carry output (h) to carry. Then, an up/down counter 6 outputs a smoothly changed digital quantity by an initial value (a), a change direction (b) after setting, and the carry output (h). Thus, influences of the converter which obtains a reciprocal of the variation are eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an apparatus for smoothly changing a digital quantity.

[Prior art]

A block diagram of a conventional device of this type is shown in FIG.

In the figure, (,) is the input initial value signal, (c) V
1 is an input change amount signal, and (f) is a manually inputted reset signal.

(1) is a computer that calculates and stores digital signals and outputs the initial value signal, variation signal, and reset signal; (2) is a register that holds the digital signals of the computer (1); (3) ) is a converter that converts the digital input signal into a value proportional to the reciprocal, (5) is a divider that divides the clock by the input value (D), and (6) is the initial value input terminal of the up/down switching input terminal. .

An up/down counter that has a clock input terminal T and performs up-counting or down-counting based on the output of the 2-way divider (5).
It is a down counter.

A conventional device of this type is configured as described above, and has a register (
2) When the amount of change (c) is set from the calculator (1), the converter (31K) sets a value (e) proportional to the reciprocal of the amount of change (c).
) is obtained by dividing the clock (g) by the output (e) of the converter.
) is set to the initial state by reset (f).

The frequency of the output signal (h) of the divider (5) is determined by dividing the frequency of the oscillator (4) by the output (e) of the converter (3). Therefore, the value is proportional to the amount of change (c).

= (number of cycles of g) x (amount of change: c) The direction of increase or decrease is determined by the change direction (b), which is the sign of (c). In addition, the up/down counter outputs a digital amount that changes bit by bit at a speed corresponding to the amount of change designated from the initial value by the initial value setting diameter signal (h).

However, as described above, since the reciprocal of the amount of change is calculated by the converter (3), it is impossible to set the amount of change "O" and there is a drawback that the output signal (1) cannot be stopped.

In order to obtain the same resolution as the amount of change for the converter (3), if the bit width of the amount of change is n, the bit width of the output (e) of the converter (3) is 2n to obtain a resolution of silobits. The disadvantage is that a 2n-bit converter and a branching unit are required for this purpose.

Since it is necessary to initialize the divider (5) after setting the amount of change, the contents of the previous divider are initialized, and there is a drawback that frequency division must be started anew after the setting.

[Embodiments of the invention]

The present invention aims to improve such problems, and an embodiment shown in the drawings will be described below.

FIG. 2 is a diagram showing an embodiment of the present invention.

+11 +2) (61 is the same as the conventional device described above.

(7) is an adder that adds two input signals, A and B.

(8) is a latch which temporarily holds the output of the adder (7) and whose output is connected to one input of the adder (7).

In the device of the present invention configured as described above, when the amount of change (c) is set in the register (2) from the computer (1), the adder (7) adds the absolute value (d) of the amount of change and the latch ( 8
). The latch (8) holds the output (j) of the adder and updates the data using the clock (g).

In this way, at time T, the adder (7) is connected to the latch (8) that holds the amount of change in the register (2) and the adder output at time T-1.
Add the outputs of . The output of the adder (7) is the oscillator (4)
When the value of the warmth adder exceeds the maximum value of the adder at two times when the amount of change is added every clock, the adder outputs a carry output (h) and the adder performs a carry.

Here, the frequency of the carry output (h) is as follows.

(frequency of h) = (frequency of oscillator) × (change t) ÷ (
Maximum value of the adder) Here, since the frequency of the oscillator and the maximum value of the adder are constant, the frequency of the carry output (h) is proportional to the amount of change.

As with the conventional circuit, the up/down counter (6) changes the initial value (3) by the amount of change set by the computer (1) based on the set radius change direction (b) and the carry output (h). It is possible to output a digital quantity that changes smoothly bit by bit.

In the above embodiment, the present device is controlled by a computer, but the same operation can be expected even if the device is manually set using a switch or the like.

[Effects of the Invention] As explained above, according to the present invention, it is possible to create an extrapolation device without co-locating a converter for calculating the reciprocal of a converter, and there is an advantage that the device to be realized can be simple and miniaturized.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing a conventional device for smoothly changing a digital amount, Fig. 2 is a block diagram showing an embodiment of the present invention, and Fig. 3 is a time chart of the main parts of the embodiment in Fig. 2. FIG. In the figure, (1) is a computer, (21Vi register,
+31Vi converter, (4) is oscillator, (5) is branching unit,
(6) is an up/down counter, (7) is an adder,
(8) is a latch. Note that the same reference numerals in the two figures indicate the same or corresponding parts. Agent Masuo Oiwa

Claims (1)

[Claims] In a device that smoothly changes a digital amount, which is composed of a register, a latch, an adder, and an up/down counter, a register that inputs and temporarily holds change amount data and an output signal of the adder are input. Input the output of the above register into the latch for temporary holding and the first input terminal of the two input terminals, input the output of the above latch into the second input terminal, and output the addition output and carry output. Initial value data is input to the first input terminal of the adder and three input terminals, the carry output of the adder is input to the second input terminal, and the data of the above register is input to the third input terminal. Enter the output and
A device for smoothly changing a digital quantity, characterized by comprising an up/down counter that increases or decreases.