JPH01269121A - Sampling signal generator - Google Patents

Abstract

PURPOSE:To efficiently fetch the change condition of an input analog signal to an external memory by generating a sampling command signal each time the differential value of the A/D converting data of an input analog signal exceeds a prescribed value. CONSTITUTION:The title generator is composed of an A/D converting part 10 and a pulse generating part 20. An input analog signal is sent to the pulse generating part 20 converted to the digital data by the A/D converting part 10. The pulse generating part 20 calculates the differential value of the introduced data and generates a pulse-shaped output each time it exceeds the value specified beforehand. The pulse-shaped output is impressed to a memory as a sampling command signal, and when the data of the A/D converting part are introduced into the memory, the data are stored each time the sampling command signal is impressed. Thus, without enlarging the memory capacity, the generator of the sampling signal to fetch the data, in which the input signal can be faithfully reproduced, is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a sampling signal generator that instructs the timing of data acquisition into a memory when an input analog signal is converted into a digital signal and stored in the memory.

BACKGROUND OF THE INVENTION Some devices of this type include a crystal oscillator and a frequency dividing circuit thereof, and are configured to generate a pulse-like sampling signal at regular intervals predetermined by the frequency dividing circuit.

Problems to be Solved by the Invention However, when data is loaded into memory using this fixed-period sampling signal, the larger the rate of change in data, the smaller the number of data sampled during that period.
There is a problem in that when the stored data is reproduced, the state of change cannot be clearly understood. That is, for example, the third
As shown in the figure (,), when the displacement (Y) of the robot arm in the Y direction changes rapidly at the beginning with respect to the passage of time (1), the data acquired by the periodic sampling signal is ) as shown in the dashed line frame, and if
If there were two inflection points instead of one, it would be impossible to reproduce them from the captured data.

To interpret this, it is possible to shorten the period of the sampling signal, but this would require a large memory capacity.

The present invention provides a sampling signal generator that can capture data that can faithfully reproduce an input signal without increasing memory capacity.

A thousand ways to solve the problem.Currently, we are considering reproducing the input signal when the amount of stored data is limited.In areas where the changes are large, a large amount of data is required to reproduce them, but where the changes are small. In some cases, the data may be decimal. In other words, by changing the data acquisition cycle according to changes in the input signal and increasing the number of acquisitions in the necessary parts, the input signal can be faithfully reproduced without increasing the overall number of data acquisitions. It will be possible to do it.

The present invention is a sampling signal generator based on the above study, and includes an A/D converter for an input analog signal and its A/D converter.
and a pulse generator that generates a pulse-shaped output every time the differential value of the /D conversion data exceeds a predetermined value.

In this, the input analog signal is converted into digital data by the A/D converter and sent to the pulse generator. The pulse generator calculates the differential value of this introduced data, and generates a pulse-like output every time the differential value exceeds a predetermined value. This pulse-like output will be applied to the memory as a sampling command signal, and if the data of the A/D converter is introduced into the memory now, each time this sampling command signal is applied, the data will be Memory takes place.

As a result, the sampling command signal is sent out at short time intervals when the rate of change of the input signal is large, and at long time intervals when the rate of change is small. When the rate of change is large, data is captured at short time intervals; conversely, when the rate of change is small, data is captured at long time intervals.

In the X1 eye I si diagram, 1 is the sampling signal generator,
An input analog signal is introduced into the internal A/D converter u10, and the output of the lowest digit of the A/D converter 10 is introduced into the pulse generator 20. Generates a pulse output every time the digit signal changes. Reference numeral 30 denotes a memory into which the conversion data of the A/D converter 10 is introduced, and the pulse input/output of the pulse generator 20 is applied to this memory 30 as a sample command signal.

In this case, a sampling command signal is sent from the pulse generator 1120 every time the least significant digit of the A/D converter 10 changes, that is, every time the input analog signal changes by the resolution of the A/D converter. , A/D at that time
Conversion data is captured into memory 30.

FIG. 2 shows another embodiment of the pulse generator, and the A/D
The converted data of the converter 10 is sent to the external memory 30, and is also sent to the delay unit 21 of the pulse generator 20' and the comparator 2.
2, respectively, and the delay unit 21. Then, the introduction data is delayed by the A/D conversion period and sent to the comparison section 22. Then, the comparing section compares both introduced data, that is, the previous and subsequent A/D converted data, and sends out a pulse output every time the difference exceeds a predetermined value.

Therefore, also in this case, a pulse output as a sampling command signal is generated every time the differential value of the input analog signal exceeds a predetermined value.

The effects of the invention are as described above, and the present invention has the following advantages:
Since a sampling command signal is generated every time the differential value of /D conversion data exceeds a predetermined value, external memory can efficiently capture the changing state of the input analog signal.
For example, it is effective for accurately forming an X, Y two-dimensional glue surge waveform.

[Brief explanation of the drawing]

FIG. 1.2 is a block diagram showing an embodiment of the present invention. 1: Sampling signal generator 10: A/D converter 20.20': Pulse generator

Claims (1)

[Claims] 1. A sampling signal generator consisting of an A/D converter for an input analog signal and a pulse generator that generates a pulse-like output every time the differential value of the A/D converted data exceeds a predetermined value.