JPS6122261A - Measurement of pulse signal - Google Patents

Abstract

PURPOSE:To make it possible to accurately and rapidly measure an impulse speed and a make ratio by a simple counter circuit, by providing two timers for timing the interval of a pulse signal and the period of a pulse. CONSTITUTION:A monitor timer 23 is started by a timer control part 21 corresponding to the measuring demand from a pulse measuring part 31 to perform time monitoring for measuring a pulse. Timers T124, T225 count the clock from a clock generation source 29 for generating a predetermined constant clock and respectively time the zero level period and a pulse cycle in the dial pulse signal TDLPS from an apparatus 10 to be measured. A processor 3 receives the timing result from a timer circuit 2 to calculate the impulse speed, the make ratio and the min. pause time shown by a pulse signal to output the same to a display apparatus 4 and a printer 5.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a pulse signal measurement method that can automatically measure the waveform of a pulse signal using a simple technique.

A device equipped with a network control unit (NCU) has a function of issuing a dial pulse for connection to a public line.

[Conventional technology]

Therefore, in the inspection process before shipping the device, an operation test of this dial pulse generation circuit is performed.

Conventionally, this NCU section was connected to a public network for testing, and its output pulses were measured using a synchroscope or the like. The pulse waveform on the synchroscope was then measured visually by the examiner.

[Problem that the invention seeks to solve]

As mentioned above, in the past, the system for testing the operation of the NCU section was large-scale, resulting in high costs. Moreover, the synchroscope measures the same level as a normal line (for example, -4.8V), and it is necessary to pay sufficient attention to the handling of the small number of workers and testers. Furthermore, the measurement of the pulse signal ultimately relies on visual observation by the tester, which poses a problem in terms of reliability of the measurement results.

[Means for solving problems]

The present invention aims to provide means for solving the above-mentioned problems. For this purpose, a first timer that measures the interval between pulse signals, that is, the time from the falling edge of a pulse to the rising edge of the next pulse, and a second timer that measures the period of one pulse are provided, and these timer outputs are provided. The device is configured to measure the waveform of a pulse signal based on the following.

[Effect]

As is well known, pulse signals are binary (marks, spaces, etc.)
It exhibits a level of Therefore, in the first timer,
By timing the mark (“L”) level period of the pulse signal and further timing the pulse period using the second timer, it is possible to easily determine the impulse speed and make rate.

Furthermore, if the pulse signal to be measured is a dial pulse in the NCU section described above, the first timer can simultaneously measure the minimum pause time between each digit.

The present invention will be explained in detail below using Examples.

〔Example〕

FIG. 1 is a diagram showing an embodiment of the present invention.

That is, in this embodiment, a TTL level +5cm voltage source 1 is applied to the NCUIO of the device under test. 2 is a timer circuit, which is a programmable measuring circuit having three timers as described later.

3 is a processor (hereinafter referred to as CPU) which receives the timing result from the timer circuit 2 and calculates the impulse speed, make rate, and minimum pause time shown in the pulse signal; 4 is a display device; 5 is a display device; This is a printer, and the calculation results by the CPU 3 are displayed or printed out.

FIG. 2 is a diagram showing a connection form between the N00 section 10 and the timer circuit 2 in the embodiment shown in FIG. That is, the output terminal from the voltage source 1 is connected to the line connection terminals 10', 10' of the N00 section 10. Furthermore, due to the resistor R and capacitor C,
A circuit is configured to prevent chattering in the output dial pulse signal. The timer circuit 2 is connected via an inverter 6 to an output terminal to which +5V is applied.

FIG. 3 is a diagram showing a general signal waveform of a dial pulse sent out from the N00 section 10. The dial pulse is
A certain period of time after polarity detection by N00 unit 10 (3 seconds in the figure)
After the elapsed time, a pulse corresponding to each digit of the dialed number is emitted. In the signal waveform of this dial pulse, the pulse period is tQ.

When the make time is tx, the impulse speed (pps) and make rate (%) in pulse measurement are expressed as follows.

1(.

Furthermore, in the pulse measurement, the dial pulse separation time (minimum pause time) tρ between each digit is also measured.

FIG. 4 is a time chart showing a pulse measurement operation in this embodiment, and FIG. 5 is a functional block diagram showing a specific configuration for performing this measurement operation. As shown in FIG. 5, the processor 3 is provided with a pulse measuring section (APL) 31 that calculates the above-mentioned impulse speed and make rate. On the other hand, the timer circuit 2 has three timer errors 25. Timer control unit (TMCNT) 21. A measuring section (TMIRQ) 22 is provided. In FIG. 4, the signal 'l'TDLPs is a pulse signal obtained via the inverter 6 (FIG. 2). It also shows the count value of the step counter of the TMSTC timer control unit TMCNT.

The monitoring timer 23 receives a measurement request (command) from the APL 31.
It is activated by the timer control unit 21 in response to the
This monitors the time for pulse measurement. Timer T
l (24) measures the time between "0" levels in the dial pulse signal: TDLPS. Also, timer T2 (
25) is for measuring the pulse period in the signal *TDLPS. Each of these timers 23, 25 is connected to a clock generation source 29 which emits a predetermined constant clock.
Count the clocks from.

The operation of this embodiment will be explained below based on the flowcharts shown in FIGS. 6 to 9. Figures 6 and 7 show CPU3
FIG. 8 is a flowchart showing the operation of the pulse measurement unit APL31 in the timer control unit TMCN in the timer circuit 2.
Flowchart showing the operation of T21 FIG. 9 is also a flowchart of the operation of the measurement unit TMIRQ22.

First, the pulse measurement unit APL31 displays a vial pulse measurement start message TSLAII as shown in FIG. 1) on the screen of the display 4 (steps 601 to 60
3). In Figure 1), the symbol SP represents a space. Next, the APL 31 clears the step counter CTME that it manages (step 604), and temporarily stores the message display line data in the display line register KA I SUU.

Then, it waits for an instruction to start pulse measurement to be input from a keyboard (not shown) (steps 606 to 607). If this instruction is input, the pulse measurement unit APL3) sets the address value TIMMEM for storing the measurement timer value in the index register IX, and also sets the timer control unit TMC.
Issue a macro command to start NT21. This macro instruction includes a parameter TMPAR that specifies the time to be measured, as shown in FIG. Therefore, in this embodiment, this parameter T
Set MPAR to 45 (hexadecimal).

According to this macro command, the timer control section 21 and the measurement section 22 measure various times in the dial pulse waveform (that is, perform the operations shown in FIGS. 8 and 9, respectively).

The end of time measurement by the timer circuit 2 is shown in FIG.
The CPU 3 is notified as termination information TMEIF as shown in (step 610). If the measurement is performed correctly, the pulse measurement unit 31 of the CRU 3 moves to the subroutine DLPSS shown in FIG. 7 (step 61), calculates the impulse speed, make rate, and pause time, and displays the calculation results in sequence. Convert to data (steps 612, 61
3). Note that register MEMO5 is a display data buffer,
MEMO3 indicates a display digit buffer.

When the display of the calculation results is completed, the pulse measuring section 31 increments the count value of the step counter CTME and moves on to the next pulse measurement. That is, in this embodiment, the step counter CTME is counted up from OO to 05. When the count value is from OO to 02, the impulse speed (00) of the dial pulse of 10 pps, the make rate (
01).

and instructs calculation of pause time (02). Count values 03 to 05 are impulse speeds of 20 pps (03),
Instructs calculation of makeup rate (04) and pause time (05).

Next, the operation of the timer circuit 2 will be explained using FIGS. 8 and 9. As mentioned above, the macro command from CPU3 (10th
The timer circuit 2 is started according to the diagram (a). First, the timer control unit TMCNT21 clears its own step counter TMSTC (step 801), and
The parameter TMPAR given by the macro instruction is read (step 802). And this parameter TMPAR
803). In FIGS. 8 and 9, operations are shown only when dial pulse measurement is specified, and other processes will be explained in detail.

The timer control unit 21 has its own step counter TMST.
Each timer operation is controlled according to the value of C, that is, the value 00-06 shown in FIG. 4 (steps 804, 808, 80
9,815). That is, the monitoring timer 23 is started with the counter TMSTC having a value of 00 (step 807).

Next, it is checked whether the pulse signal 1kDLPs has fallen to the O level (810). After detecting the polarity, detect the rise of the first dial pulse (step 81))
. Then, at the falling edge of the dial pulse, timer T1
and Tz (24, 25) (step 81
2-814).

Next, due to the rising edge of the dial pulse, the measurement unit TMIRQ
22 is activated (steps 901, 902). Then, according to the value of the step counter TM-3TC (90
3,904) Each timer T1°Tz is read (
905. ! 306, 909), reading of each of these timers is executed in each subroutine TISTRM and T2STRM, and the timer value is stored in the area corresponding to the address stored in the index register IX12 (917). As described above, each time measurement is performed by the timer circuit 2.

As a result, as shown in FIG. 10 (C1), each time of make, period, and pause is written as a count value of the counter on a predetermined address of the memory and is notified to the CPU 3.The pulse measurement unit 31 of the CPU 3 As described above, each measured value is read out based on the termination information TMEIF from the counter circuit 2.

That is, as shown in FIG.
In accordance with the value of E (steps 701 to 704), the impulse speed (707), make rate (7I4), and pause time (71) are calculated and converted into display data.

[Effects of the Invention] As described above, according to the present invention, the waveform of a pulse signal can be measured more accurately and quickly using a simple counter circuit.

[Brief explanation of drawings]

Fig. 1 is a diagram showing an embodiment of the present invention, Fig. 2 is a diagram showing the main part of the embodiment, Fig. 3 is a diagram showing a general waveform of a dial pulse signal, and Fig. 4 is an operation of this embodiment. FIG. 5 is a functional block diagram, FIGS. 6 to 9 are operation flowcharts, and FIG. 10 1a) to (flt) are data formats in the operation flowcharts.
) The figure does not show an example of a displayed message. 2 is a timer circuit, and 3 is a processor (CPU). 4 is a display, 21 is a timer control section, 22 is a measurement section, 23 to 25 are timers, and 31 is a pulse measurement section.

Claims (2)

[Claims] (1) In a device that measures the waveform of a pulse signal emitted by a signal sending device, there is a monitoring timer that is activated by an instruction to start measurement of the pulse signal and measures a certain period of time, and a monitoring timer that measures the time from the fall to the rise of the pulse signal. Pulse signal measurement characterized by comprising a first timer and a second timer that measures the period of the pulse signal, and measuring the waveform of the pulse signal based on the output values of the first and second timers. Method. (2) The signal sending device generates dial pulses consisting of multiple digits, and the first timer measures the pulse interval in each digit and the minimum pause time between each digit. The pulse signal measuring method according to the range (1) above.