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Pc based oscilloscope

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aibelectronics

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pic based oscilloscope

Does anyone have any info on pc based oscilloscope? i found one schematic at electronicsforu, but the code was somewhat too cryptic.
Any info? thanks.:|
 

jonw0224

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pic based pc oscilloscope

There was a forum about this a few months ago:



I also am building a PC based oscilloscope using a PIC microcontroller and a MAXIM ADC. It's kind of a fun toy, but alot of work to design from scratch. I had a working version (200 kHz sample rate), but I took it apart to do improvements (deeper channel memory and 1 MHz sampling rate).

Unless you want to do a lot of code, I recommend you buy or try to build a bitscope.

If anyone is interested in seeing what I've done, I'll post to the web but it may take a week or two.
 

aibelectronics

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pc based oscilloscope schematic

a bitscope? well not reaallly. It seems a more complex bargain than what I have already. :?
 

checkmate

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diy pc based oscilloscope

A 1MHz sampling rate from a pic is amazing!

Anyway, if you are thinking of building one up out of a microcontroller and ADC, what you would have to consider is getting any decent sampling rates.

Drawing a sample from a ADC is going to take a couple of cycles. You have to consider the DAC sampling delay too. After that, you need to store it somewhere. uCs have extremely limited memory, so captured signals are limited in length. To transfer sampled data to external memory, or even to a PC through any interface will be going to take even more processor and communication overheads.

Given the fastest PIC at 10MIPs (Or is it 12MIPs?), you can give an estimate on how many kilosamples to expect.
 

jonw0224

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oscilloscope code

I believe with the help of an external buffer or memory, I can get the sample time down to 5 cycles (using a 20 MHz clock is 1 MHz). I haven't actually built the hardware, but the code works for a 4 MHz clock (hince the 200 kHz sample rate). The sampling loop is expanded using macros (all loop handling is done at compile and not with a counter). I'm using a MAX118 as the ADC. I'm not sure about the timing of the maxim chip at 1 MHz, but the datasheet says it should handle it. I'll post an update when I get it working (when I get my new PIC).

I'm also adding a continuous delay to do repetative waveforms at 1 cycle (2.5 Mhz bandwidth).
 

pat35

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50 khz sound card oscilloscope

Hi I am new to this site. . Right now my 4 channel scope is destroyed. I am looking to build a new one. I really like Colin's project(at the link below) with 4 channel scope but I can't write code. I have not been able to find anyone that can write code. Does anyone know any other scopes that are 4 chanel that I can make? Has anyone made a 4 channel or has completed this scope? h**p://www.mccord.plus.com/FYP/DownLoad/Final_Report.pdf

Any help woud be appreciated.
Thank you!
Pat
 

Jack// ani

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oscilloscope pc soundcard 200khz

I've seen a very simple yet useful oscilloscope based on half flash ADC0820, can't find the link. Search in google...
 

Sceadwian

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computer based oscilloscope circuit

It's not as much fun as building one yourself, but lurk around on e-bay. I picked up an old HP/Agilent 500khz dual trace scope that works fine for 30 bucks. (Your mileage may vary) It's not digital and it's not PC based, but if you 'really' need those features you're gonna end up paying hard cash for it.
 

pat35

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pc oscilloscope schematic

i have 3 portable ones a fluke,2 tektronixs. all are great but need a 4 chanel scope woud like to learn how to make and its challenging to try.I bought 2 books on code but it will be a while before i can even start trying.
Any info would be appreciated!
Pat
 

rangarirai

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sample oscilloscope cod vb

i am actually in the process of designing one and am using a PIC16F872 microcontroller and interfacing through a serial port then for the programming of the user interface i am using VB.NET.There is quite a lot of work to be done in as far as frequency,aliasing and amplitude considerations are concerned .for a general overview of the system design i found the information at **broken link removed** quite helpful.
 

pat35

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oscilloscope diy ad9280

i am interested in what you are making do you think you will have any info or schismatic in the flusher if so how can i get intotuch with you my email ste895#bellsouth.net
pat
 

seadolphine2000

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jonw0224,...

Would you mind posting the schematic for you scope.???

Thanks very much. :)
 

jonw0224

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oscilloscope on my pc

seadolphine2000,

My schedule is pretty constrained the next couple of weeks, so I can't guarrantee a quick response to your request.

Perhaps I can post the schematic, code, and executables (both pic and pc) to my website for the 200 kHz version in the next two weeks. It may not be documented the best. By no means is the code a final version! I'll post here when its uploaded.

My goal is to get the 1 MHz version working, but I don't get alot of time to work on this project (maybe 2 to 4 hours a week - that's how it is when you're young, married, have a full time job, and home to take care of - I'm so blessed - this is a hobby afterall and low on the list of things to do but very enjoyable and sometimes a little frustrating. I digress).

I've got a prototype assembled on my circuit board, but as I test the analog parts of the circuit I am finding room for improvement and am making changes (like input signal protection, preventing clamping, saturation, adding triggering, etc.). The schematic for the 1 MHz version is a moving target right now (but moving slower). I'm almost to the point of rewriting code to reflect all the changes. Hopefully, it will plug into the PC software and work when I get to that point. Then its on to adding features and more modes of operation. I could have bought an oscilloscope by now, but its been fun.
 

artem

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guterman final scope 1.htm
 

seadolphine2000

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sound card oscilloscope increasing frequency

Hi,...
I want to build the scope in the link below but couldn't find this fast ADC0820, so cpuld anyone give me another part that is quite similar to this.???
https://www.geocities.com/lptscope/index.html

Thanks very much for all your help.
 

jonw0224

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pic16f872 oscilloscope

Hi all. I have posted the schematics, etc. for the oscilloscope to my webpage at:

https://jonw0224.tripod.com/ppmscope.html

I am still hard at work on the 1 MHz version. Sorry it took a while for me to get this posted.

Checkmate, I noticed where you were asking about kilosamples. Right now, I am storing values in the pic ram, so expect a couple of hundred samples. I could add a ram chip somehow to expand on this, but for my purposes a couple of hundred was enough.
 

aibelectronics

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pc sound card oscilloscope input protection

1MHz? wow that's pretty high. i'm currently looking at the oscilloscope on this page:**broken link removed** the problem is that the maximum signal frequency it can display is 1khz which compares very poorly with the 1Mhz you're talking about. How do i increase the frequency range to even as low as say 100khz.

some people have told me to use usb port, but i don't want to do that because i've already bought the adc 0804 - it was expensive, and that i should use a faster opamp than the lm 324 and use lower sampling time.

what's your ideas about how to improve this particular one, i don't want to do much drastic changes for i've bought all the major components.

thanks.:|
 

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