JPS61156923A - Pcm dynamic simulator - Google Patents

Abstract

PURPOSE:To obtain a PCM dynamic simulator having a function possible for dynamic change by decoding a synchronizing signal and using the result as a reference to change a bit pattern of a prescribed word into a desired pattern in a real time. CONSTITUTION:A synchronizing signal detecting circuit 31 detects synchronizing signals S1, S2... of PCM serial data 21a and gives a trigger signal 31a to a counter circuit 32. The counter circuit 32 uses the said trigger signal as a start control signal and when the count of a word clock 32a is coincident with a set bit pattern, a switch control signal 32b is outputted to a switch circuit 34 and a bit pattern setting circuit 33. The bit pattern setting circuit 33 outputs a new bit pattern 33a to the switch circuit 34, which outputs switchingly the inputted PCM serial data 21a and the said new bit pattern 33a based on the switch control signal 32b. Thus, the data is changed dynamically to a desired bit pattern in a desired timing without giving any effect on the output device.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a PCM dynamic controller used for dynamic testing of, for example, digital circuits and digital signal processing systems.

[Technical background of the invention]

Conventionally, PCM simulators have been used as test signal generators to test the dynamic functions and performance of digital signal processing systems including digital circuits or software.

FIG. 4 is a dynamic test system diagram of a conventional digital signal processing system, and is similar to IJIfiPCM in the figure.

The PCM serial data l1m of the PCM stain simulator 11 is the PCM serial data l1m in the digital signal processing system lo.
The signal is decoded by a decoder 12, processed by a digital signal processing device 3 such as a computer, and subjected to a dynamic functional test.

There are some PCM stain simulators that output only a simple fixed i4 turn depending on the lid usage, and others that are complex and can change the output pattern, such as simulating a satellite telemetry signal.

[Problems with background technology]

However, among these PCM simulators that can change the output and turns, there are some in which the output is interrupted during the change of 74 turns (change of data format, pit amount turn, etc.) #-i. This poses a problem when performing a dynamic functional test on the digital signal processing system 1o, for example. This is because the interruption of the input causes the PCM decoder 12 of the digital signal processing system 10 to lock off.

On the other hand, a PCM simulator that generates only a simple fixed pattern is useful when testing static characteristics, but cannot be used when changes over time are required.

Furthermore, there is no device that can be used to dynamically change not only the output of a test signal generator such as a PCM simulator, but also a part of general PCM serial data.

[Purpose of the invention]

This invention was made in order to eliminate the above-mentioned conventional drawbacks, and it is possible to use the output of a PCM simulator or
An object of the present invention is to provide a PCM dynamic controller having a function of dynamically (in real time) changing part of M serial data.

[Summary of the invention]

The PCM dynamic simulator of the present invention is a PCM dynamic simulator in which a synchronization signal is added between data of every known word at a constant period.
In the PCM dynamic simulator, this synchronization signal is decoded from the serial data, and using it as a reference, the 1,000-bit turn of a predetermined word is changed to the desired 1,000-turn in real time.

[Embodiments of the invention]

Embodiments of the PCM dynamic simulator of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of one embodiment.
21 in the figure is a PCM code generator such as #iPCM Simiereme.

PCM serial data 21h is transferred from the PCM code generator 2 to the PCM dynamic simulator 22. This PCM series full f-tater 21
As is clear from the data format shown in FIG. 2, synchronization signals Sl, S2 . . . are added to the words Wl, W2, .

The PCM dynamic controller 22 decodes this synchronization signal, uses it as a reference, changes the setting of the pit nozzle turn of a predetermined word to a desired pattern, and transfers it to the digital signal processing system 23. .

FIG. 3 is a block diagram showing the internal structure of the PCM dynamic controller 22, in which the PCM serial data 21h is input to the synchronization signal detection circuit 31 and the switching circuit 34.

The synchronizing signal detection circuit 3 detects the synchronizing signal and outputs a trigger signal 31m to the counter circuit 32.

This counter circuit 32 is configured to receive a word clock, 32 &. The counter circuit 32 uses the trigger signal 31a as a start control signal to perform word clock,
2& and outputs the count result to the switching circuit 34 and the bit turn setting circuit 33.

Bit pattern setting circuit 33 and switching circuit 34 are configured to receive bit black and red signals 35 as input. The bit pattern setting circuit 33 inputs a bit pattern 35 based on the output of the counter circuit 32, sets a new bit pattern 33h, and sends this new bit pattern 33h to the switching circuit 34.

The switching circuit 34 uses the output of the counter circuit 32 as the switching control signal 32b to generate new bit patterns 33& and PCM7.
The real data 21a is switched and output based on the bit clock 35.

Next, the operation of the PCM dynamic controller of the present invention constructed as described above will be explained. The PCM serial data 21h as shown in FIG.
The signal is input to a synchronizing signal detection circuit 31 and a switching circuit 34 in the combinator 22.

The synchronization signal detection circuit 31 detects the synchronization signal SL+S! of the PCM serial data 21 &. +... is detected, trigger signal 31
m is sent to the counter circuit 32.

Accordingly, the counter circuit 32 uses this trigger signal as a start control signal to count word clocks 32m. When the count value of the word clock 32m matches the word to be changed to the set bit pattern, the switching control signal 32b is output to the switching circuit 34 and the bit pattern setting circuit 33 during the word transmission period.

In the data 7ohm, g24 of FIG. 2, the word W
An example of changing the bit pattern 25 of n is shown below, where the bit pattern is changed to the second and mth bits)2. It shows that m has been changed, and bit pattern 26 shows an example after the change.

The bit pattern setting circuit 33 allows an operator to set a desired bit pattern from a panel or the like (not shown) together with a word shop, and during a control period by the switching control signal 32b (
A new bit pattern 33 & is output to the switching circuit 34 during the on state).

The switching circuit 34 receives input PCM serial data 21.
h and this new bit pattern 33& are switched and output based on the switching control signal 32b.

In addition, in Figure 3, word clock, ri32IL1bi, tokuro, and ri35 are written as being given from the outside,
This is because common PCM simulators supply them as output signals. However, if these signals are not given, the PCM serial data 21a
It is necessary to create a new bit synchronization circuit added from the beginning.

〔Effect of the invention〕

As described above, according to the PCM dynamometer and combinator of the present invention, the PCM serial data in which a synchronization signal is added between word data at regular intervals is detected by the PCM dynamometer and combinator, and the synchronization signal is detected. Since the bit/arm turn of a predetermined word is changed to the desired bit pattern in real time based on the synchronization signal, the PCM serial data, which is fixed in time, has no effect on its output device. Data can be dynamically changed to a desired bit/4 turn at a desired timing without any trouble.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of an embodiment of the PCM dynamic simulator of the present invention, Fig. 2 is a diagram showing the data format of PCM serial data applied to the above PCM dynamic simulator, and Fig. 3 is an internal diagram of the above PCM dynamic simulator. A system diagram of one embodiment of the configuration, FIG. 4 shows the dynamics of a conventional digital signal processing system,
FIG. 2: PCM code generator, 22: PCM dynamic generator, 23: digital signal processing system.

Claims (1)

[Claims] P with a synchronization signal added at regular intervals between word data
A PCM dynamic simulator that detects a synchronization signal from CM serial data and changes the bit pattern of a predetermined word to a desired pattern in real time based on the detected synchronization signal.