Background technology
In the prior art, the main composition of digital oscilloscope as shown in Figure 1, it comprises: controlled processing unit, external analog signal input block (AFE (analog front end)), LCD display unit, keyboard input block and power supply, and wherein: controlled processing unit is made up of CPU, storer, logical circuit; AFE (analog front end) is made up of probe 102, VGA amplifier 101 and analog to digital converter (A/D).
Digital oscilloscope of the prior art generally comes display waveform with the traditional display modes of single forms, that is to say that signals such as channel C H1, CH2, CH3, CH4, MATH all show in same forms.Because base has only one when oscillographic, just channel C H1, CH2, CH3, CH4 only can trigger the source triggering synchronous with one.Though therefore this display mode can satisfy most of needs of measuring,, when measuring some sophisticated signals, its weakness just obviously embodies.As when surveying an amplitude-modulated signal, because base has only one when oscillographic, when display waveform, just only can observe amplitude-modulated signal or carrier signal like this, can't observe carrier wave and modulating wave simultaneously, make analysis waveform become complicated more.
As shown in Figure 7, in the prior art, when observation signal on the forms of oscillograph display screen, only can observe the profile or the details of waveform, and can't promptly observe the overall profile of waveform simultaneously, observe the waveform details again.And when two passages are observed the signal of different frequency simultaneously, when particularly frequency differs bigger, in the time of one, often can't observe the overall profile of two signals under the base simultaneously.
Summary of the invention
The object of the present invention is to provide a kind of method for displaying waveform and digital oscilloscope of digital oscilloscope, with so that digital oscilloscope can show two forms (Main form and postpone forms) simultaneously, and can make digital storage oscilloscope more directly perceived when showing distinctive signal, convenient with different time basic display waveforms on two forms.
In order to realize above-mentioned goal of the invention, the invention provides: a kind of method for displaying waveform of digital oscilloscope, described method is applicable to digital oscilloscope, it may further comprise the steps: gather external analog signal and be digital signal with the analog signal conversion of gathering; Receive described digital signal and be stored as digital signal data; Receive external echo and generate first forms parameter of first passage and the second forms parameter of second channel, and draw the first forms scaling and the second forms scaling according to the first forms parameter and the second forms parameter; Read the digital signal data of storage, and the digital signal data that reads is carried out the convergent-divergent processing, generate first video data of first passage and second video data of second channel according to the first forms scaling and the second forms scaling; The waveform and/or the data of the pairing first passage of first video data are shown with first o'clock base at described first forms; The waveform and/or the data of the pairing second channel of second video data are shown with second o'clock base at described second forms.
Described first forms are Main form, and described second forms are for postponing forms; Scaling according to Main form carries out the convergent-divergent processing to the digital signal data that reads, and generates main video data; According to the scaling that postpones forms the digital signal data that reads is carried out convergent-divergent and handle, generate the delay video data; Pairing waveform of main video data and/or data are shown at described Main form; To postpone pairing waveform of video data and/or data shows at described delay forms.
In order to realize above-mentioned goal of the invention, the present invention also provides a kind of digital oscilloscope, and this digital oscilloscope comprises: collection of simulant signal device, analog-digital commutator, control and treatment device, memory storage, external echo device and display device; Described collection of simulant signal device is connected with the control and treatment device by analog-digital commutator, and described memory storage, external echo device and display device are connected with the control and treatment device respectively; This digital oscilloscope also comprises: waveform processing device, this waveform processing device are connected with analog-digital commutator with described control and treatment device, memory storage respectively; Wherein: described control and treatment device, the instruction that receives the external echo device generates first forms parameter of first passage and the second forms parameter of second channel, and draws the first forms scaling and the second forms scaling according to the first forms parameter and the second forms parameter; Described waveform processing device further comprises: the digital signal receiving element is used to receive that the collection of simulant signal device is gathered and by the digital signal of analog to digital conversion dress conversion, and deposits the digital signal that receives in described memory storage; The scaling receiving element is used to receive the first forms scaling and the second forms scaling that the control and treatment device transmits; The digital signal unit for scaling, be used for reading the digital signal data of storage from described memory storage, and according to the first forms scaling and the second forms scaling digital signal data that reads is carried out convergent-divergent and handle, generate first video data of first passage and second video data of second channel; First video data that described waveform processing device will generate and second video data send described control and treatment device to, described control and treatment device is controlled described display device the waveform of the pairing first passage of first video data and/or data is shown with first o'clock base at described first forms, and the waveform and/or the data of the pairing second channel of second video data are shown with second o'clock base at described second forms.
Described display device is a display screen.
Described display device also can be made up of two display screens, and pairing waveform of main video data and/or data are shown on a display screen; To postpone pairing waveform of video data and/or data shows on another display screen.
Described external echo device comprises keyboard, mouse, touch-screen, communication interface.
Beneficial effect of the present invention is, by method for displaying waveform and the digital oscilloscope that a kind of digital oscilloscope is provided, realizes the careful observation to sophisticated signal, can observe the profile clearly of amplitude-modulated signal and carrier signal simultaneously.
When two passages are observed the signal of different frequency simultaneously, when frequency differs bigger when special, can show 1 channel signal at Main form, delay aperture shows 2 channel datas, so just can guarantee two channel datas of observing of clear, while.
Embodiment
Below in conjunction with description of drawings the specific embodiment of the present invention.
Embodiment 1
As shown in Figure 3, the present invention is a kind of method for displaying waveform of digital oscilloscope, and this method is gathered external analog signal by the AFE (analog front end) of digital oscilloscope, and this AFE (analog front end) is made up of passage 1 front end (CH1), passage 2 front ends (CH2) and other front ends.It is digital signal with the analog signal conversion of gathering that AFE (analog front end) sends the simulating signal of gathering to analog to digital converter (ADC).With the storage depth of described digital signal sequential storage to digital oscilloscope.Generate Main form (first forms) parameter and postpone forms (second forms) parameter behind the configuration-direct of control and treatment device reception external echo device then, and according to the Main form parameter, postpone the forms parameter and generate the Main form scaling and postpone the forms scaling, and with the Main form scaling that generates with postpone the forms scaling and send the waveform processing device to timely base, sampling rate.The waveform processing device is carrying out carrying out following convergent-divergent treatment step (as shown in Figure 5) when convergent-divergent is handled: if the Main form scaling more than or equal to 1, then dwindles processing to the data that read from memory storage; If the Main form scaling less than 1, then carries out processing and amplifying to the data that read from memory storage.If postpone the forms scaling more than or equal to 1, then the data that read are dwindled processing from memory storage; If postpone the forms scaling less than 1, then the data that read are carried out processing and amplifying from memory storage.To cross convergent-divergent handles the back main video data of generation and postpones video data.
Main video data and delay video data after the waveform processing device is handled convergent-divergent send the control and treatment device to.The control and treatment device is controlled described display device pairing waveform of main video data and/or data is shown at described Main form, to postpone pairing waveform of video data and/or data and show that at described delay forms two forms all show on same display screen.
Realization can be observed the profile clearly of amplitude-modulated signal and carrier signal during to the careful observation of sophisticated signal simultaneously.When two passages are observed the signal of different frequency simultaneously, when frequency differs bigger when special, can show 1 channel signal at Main form, delay aperture shows 2 channel datas, so just can guarantee two channel datas of observing of clear, while.
Embodiment 2
Be illustrated in figure 2 as the digital oscilloscope of realizing the inventive method, this digital oscilloscope comprises: collection of simulant signal device, analog-digital commutator, the CPU as the control and treatment device, storer, as the keyboard (also can adopt touch-screen, mouse, current interface etc.) of external echo device, as the LCD of display device; Described collection of simulant signal device is connected with CPU by analog-digital commutator, and LCD is connected with CPU; This digital oscilloscope also comprises: the waveform processing device, this waveform processing device is connected with described CPU, storer and analog-digital commutator respectively.
The instruction that CPU receives keyboard generates the first forms parameter and the second forms parameter, and draws the first forms scaling and the second forms scaling according to the first forms parameter and the second forms parameter.
As shown in Figure 4, described waveform processing device further comprises: the digital signal receiving element is used to receive that the collection of simulant signal device is gathered and by the digital signal of analog to digital conversion dress conversion, and deposits the digital signal that receives in described memory storage; The scaling receiving element is used to receive the first forms scaling and the second forms scaling that CPU transmits; The digital signal unit for scaling, be used for reading the digital signal data of storage from described memory storage, and according to the first forms scaling and the second forms scaling digital signal data that reads is carried out convergent-divergent and handle, generate first video data and second video data; First video data and second video data that described waveform processing device will generate send CPU to, CPU controls described display device pairing waveform of first video data and/or data is shown at described first forms, and pairing waveform of second video data and/or data are shown at described second forms.Two forms all show on same LCD display.
Embodiment 3
The ultimate principle of digital oscilloscope of the present invention, with reference to figure 6: this digital oscilloscope has mainly comprised AFE (analog front end), analog to digital conversion (ADC) conversion of signals, field programmable gate array (FPGA) cell data is handled, control, the control of digital signal processing (DSP) system, high-speed memory (SRAM), keyboard, LCD.
It is gain, skew, the bandwidth control that realizes signal that AFE (analog front end) mainly acts on, and control signal is from FPGA, and control information transfers to FPGA from DSP.
It is digital signal that the ADC conversion of signals mainly acts on the analog signal conversion that front end is conditioned, and delivers to FPGA for processing.
The instruction of DSP reception external echo device generates the Main form parameter and postpones the forms parameter, and draws the Main form scaling and postpone the forms scaling according to Main form parameter and delay forms parameter.
The major function of FPGA comprise data processing, logic control, triggering, the time base control etc., it is the core of whole digital oscilloscope.Have a waveform processing device among the FPGA, this waveform processing device further comprises: the digital signal receiving element is used to receive the ADC signal and stores the ADC signal data that receives into SRAM; The scaling receiving element is used to receive Main form scaling and the delay forms scaling that DSP transmits; The digital signal unit for scaling is used for reading from SRAM the digital signal data of storage, and with delay forms scaling the digital signal data that reads is carried out convergent-divergent according to the Main form scaling and handle, and generates main video data and postpones video data.Main video data that FPGA will generate and delay video data send DSP to.
The technology of convergent-divergent (Ultrazoom) realizes principle process with reference to the accompanying drawings 5, wherein the waveform processing device is carrying out carrying out following convergent-divergent treatment step when convergent-divergent is handled: if the Main form scaling more than or equal to 1, then dwindles processing to the data that read from memory storage; If the Main form scaling less than 1, then carries out processing and amplifying to the data that read from memory storage.If postpone the forms scaling more than or equal to 1, then the data that read are dwindled processing from memory storage; If postpone the forms scaling less than 1, then the data that read are carried out processing and amplifying from memory storage.To cross convergent-divergent handles the back main video data of generation and postpones video data.
When the ADC acquired signal to FPGA field programmable gate array (Field Programmable GateArray), FPGA itself is the cell array of standard, there is not the general function that IC had, but the user can be according to the needs of oneself, by special placement-and-routing's instrument programmed in its inside, design the special IC of oneself.Because FPGA carries out parallel processing with pure hardware mode, and does not take the resource of CPU, makes system can reach very high performance.
DSP receives main video data and the delay video data that FPGA transmits, and control LCD pairing waveform of main video data and/or data are shown at described Main form, will postpone pairing waveform of video data and/or data and show at described delay forms.Afterwards, DSP reads the total data of high-speed SRAM.
Dsp system has comprised every functions such as data processing, demonstration, interface, Message Processing, and it is powerful, and having wide range of applications is the soul of whole digital oscilloscope.
Fig. 8 is for adopting the synoptic diagram of two forms display waveforms, and the demonstration (as shown in Figure 7) of it and prior art has tangible difference.Adopt above technical scheme can reach following technique effect:
1) realization is to the careful observation of sophisticated signal.Generally speaking, when only at the Main form observation signal, only can observe the profile or the details of waveform, and can't promptly observe the overall profile of waveform simultaneously, observe the waveform details again.As shown in Figure 8: when observing an amplitude-modulated signal, use the Ultrazoom technology, can observe the profile clearly of amplitude-modulated signal and carrier signal simultaneously.
2) when two passages are observed the signal of different frequency simultaneously, when frequency differs bigger when special, the overall profile that in the time of one, often can't observe two signals under the base simultaneously.In this case, use the Ultrazoom technology to show 1 channel signal at Main form, delay aperture shows 2 channel datas, so just can guarantee two channel datas of observing of clear, while.
In embodiment 3, there is a possibility, that is: adopts two LCD display, be connected with DSP respectively, one is used to show Main form and Wave data thereof, another display delay forms and waveform number thereof, two LCD display can wait size, also can different sizes.
Above embodiment only is used to illustrate the present invention, but not is used to limit the present invention.