JP2606475B2 - Waveform storage device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a waveform storage device,
In particular, the present invention relates to a waveform storage device effective for use in a digital oscilloscope, a waveform analysis device, and the like.

[0002]

2. Description of the Related Art FIG. 3 shows a conventional waveform storage device of this type. This device is an attenuator 5
1, a preamplifier 52, an A / D converter 53, a data storage memory 54, a waveform display unit 55, a trigger circuit 56, and a controller 57. An analog signal is input to the attenuator 51, and the waveform of the analog signal is stored in the data storage memory 54 as digital data. That is, after the analog signal is input to the attenuator 51, the signal is amplified by the preamplifier 52 and is then amplified by the A / D converter 5.
In step 3, the data is converted into digital data. At this time, when a trigger pattern is set in the trigger circuit 56 by a command from the controller 57, the trigger point of the analog signal is detected by the trigger circuit 56, and the digital data to be stored according to the detection trigger is designated in the data storage memory 54. Stored in the area. When displaying the digital data stored in the data storage memory 54, the digital data to be displayed is searched by software, and the contents of the searched data are displayed on the waveform display unit 55. Thus, in the conventional waveform device, if the controller 57 searches the storage area of the data storage memory 54 by software, the data to be displayed can be searched.

[0003]

However, in the above-described conventional waveform storage device, since the search for the data to be displayed by the controller 57 depends on software, the data search cannot be performed at a high speed. There was a point.

An object of the present invention is to solve such a conventional problem and to provide a waveform storage device capable of retrieving digital data stored in storage means at a high speed. is there.

[0005]

According to the present invention, there is provided an analog / digital conversion means for converting an analog input signal into digital data, and a first trigger detection means for detecting a trigger of the analog input signal. Storage means for storing digital data obtained by the analog / digital conversion means in a designated area in accordance with a detection trigger of the first trigger detection means, and digital / analog conversion for converting the digital data stored in the storage means into an analog signal Means, second trigger detection means for detecting a trigger of an analog signal obtained by the digital / analog conversion means, and data extraction means for extracting designated digital data from the storage means in accordance with the detection trigger of the second trigger detection means. Having a waveform storage device.

[0006]

Therefore, according to the present invention, when an analog signal is stored as digital data, the analog signal is stored in a designated area in accordance with the detection trigger of the first trigger detection means, and when the stored digital data is extracted, the second trigger is used. Since the designated digital data is extracted from the storage means in accordance with the detection trigger of the detection means, the data can be searched at a higher speed than when searching for the data by software.

[0007]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a configuration diagram showing one embodiment of a waveform storage device according to the present invention, and FIG. 2 is a waveform diagram of an analog input signal. 1, the waveform storage device includes an attenuator 1, a preamplifier 2, an A / D converter 3, a data storage memory 4, a waveform display unit 5, a D / A converter 6, a switch 7, a trigger circuit 8, and a controller 9. An analog signal is input to the input terminal 10 of the attenuator 1. The analog signal is converted into a signal of an appropriate size in the attenuator 1,
The converted analog signal is A / D
The signal is amplified within the dynamic range of the converter 3.
Then, the amplified analog signal is converted into digital data by the A / D converter 3. This digital data is stored in a designated area of the data storage memory 4 in accordance with a command from the controller 9. Then, when the analog signal is amplified by the preamplifier 2, as shown in FIG.
An analog signal is input to the trigger circuit 8 via the switch 7, and the glitches 21 and 22 are used as trigger points for the analog signal.
2, and 23 are sequentially detected, and each detection trigger is transferred to the controller 9. The controller 9 stores digital data in a designated area in accordance with the detection trigger. The digital data stored in the data storage memory 4 is displayed as a waveform on the waveform display unit 5 in accordance with a command from the controller 9, and is converted into an analog signal in the D / A converter 6 in accordance with a command from the controller 9. ing. At this time, when the switch 7 is switched to the D / A converter 6 in accordance with a command from the controller 9, the glitches 21, 22, and 22 of the analog signal obtained by the D / A converter 6 are obtained.
23 are respectively detected by the detection circuit 8. Then, a search for extracting specified data from the data stored in the data storage memory 4 is performed under a trigger condition according to the data of each glitch.

In the above configuration, when the switch 7 is switched to the preamplifier 2 in response to a command from the controller 9, the glitches 21, 22, and 23 of the analog signals are detected by the trigger circuit 8, and the analog signals are sequentially converted into digital data. Is done. Each digital data is sequentially stored in a designated area of the data storage memory 4 according to the detection trigger. Next, when displaying the digital data stored under the trigger condition, the controller 9
When the switch 7 is switched to the D / A converter 6 by a command from the D / A converter 6, the digital data stored in the data storage memory 4 is sequentially converted into an analog signal by the D / A converter 6. The glitches 21 and 22 of this analog signal
2 and 23 are detected by the trigger circuit 8, respectively.
When the detection trigger is transferred to the controller 9, the controller 9 generates an address according to the detection trigger, and extracts specified digital data from the data storage memory 4 according to the address. Then, the waveform of the digital data extracted from the data storage memory 4 is displayed on the waveform display unit 5.

As described above, according to this embodiment, the digital data stored in the data storage memory 4 is converted into an analog signal by the D / A converter 6, a glitch of the analog signal is detected, and the detected glitch is detected. , An address related to the designated digital data is generated, and the data is searched according to the address. Therefore, the digital data can be searched at high speed without providing new dedicated hardware. In the above embodiment, the trigger circuit 8 is used as the first trigger detecting means and the second trigger detecting means.
Can be omitted.

In the above embodiment, the memory length is 1M.
In the case of searching for a glitch signal in a word, if it is performed by software as in the prior art, it takes more than 10 seconds to search even if a 16-bit CPU is used. Performs a data search within one second. That is, the data search can be performed at least 10 times faster than when searching by software.

[0011]

As apparent from the above embodiment, the present invention detects a trigger of an analog signal, stores digital data in a designated area in accordance with the detection trigger, and converts the stored digital data into an analog signal. Since the trigger of the analog signal is detected and the designated digital data is extracted from the storage means in accordance with the detection trigger, the data can be searched at a higher speed than when the data is searched by software.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a waveform storage device according to an embodiment of the present invention.

FIG. 2 is a waveform diagram of an analog input signal according to the embodiment.

FIG. 3 is a block diagram showing a conventional waveform storage device.

[Explanation of symbols]

 Reference Signs List 1 attenuator 2 preamplifier 3 A / D converter 4 data storage memory 5 display unit 6 D / A converter 7 switch 8 trigger circuit 9 controller

Claims (1)

(57) [Claims] An analog / digital conversion means for converting an analog input signal into digital data, a first trigger detection means for detecting a trigger of the analog input signal, and a digital data obtained by the analog / digital conversion means, Storage means for storing in a designated area in accordance with a detection trigger of the trigger detection means, digital / analog conversion means for converting digital data stored in the storage means into an analog signal, and conversion of an analog signal obtained by the digital / analog conversion means A waveform storage device comprising: second trigger detection means for detecting a trigger; and data extraction means for extracting specified digital data from the storage means in accordance with a detection trigger of the second trigger detection means.