17 channel logic analyser

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Dippy

Moderator
Do you want someone to comment on the claimed performance or actual performance?
If actual performance then - don't know.

I feel it's a little ambiguous calling it an "oscilloscope" as it isn't in the tradtional sense of the word. I realise the author has qualified it with "digital", but that could still confuse the Newbie. It's a logic analyser with a graphical display.

Having said all that and if it works as claimed then I'm sure it would be very useful.


I see many SPI / Serial / I2C projects on this Forum that get bogged down because people can't measure what is actually going on.
I've just been working with troublesome SPI , I think it could have helped.


As it's free what's the debate about?
Have a go. Let us know if it's any good then I'll get a copy too.
 
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MartinM57

Moderator
A quick read seems to indicate that it diddles with some low level stuff on the PC, so I'd be a bit wary of installing it on my prime machine/one that I would find it awkward to rebuild.

I might try it in a brand new VirtualBox first just to make sure there's no nasties - but I'm not sure how many PCs that can run VirtualBox would have a parallel port anyway.

I also note its at V1.0 - who buys (even if it's free) V1.0 of a software poduct?
 
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Dippy

Moderator
"who buys (even if it's free) V1.0 of a software poduct?"
- someone else :)

Note to Self:-
Must remember to release new software as Version 2.1 or greater, so that Martin buys it.
 
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papaof2

Senior Member
MartinM57 said:
I also note its at V1.0 - who buys (even if it's free) V1.0 of a software poduct?
Click to expand...
I try to avoid any version X.0 software, even from big companies.

Same with the first couple of years of a new vehicle design - it often takes longer to shake out (sometimes literally) mechnical and electro-mechanical problems than software problems. Ford had an electrical design problem with a cruise control that caused vehicles to spontaneously combust with the engine off and cold. That problem took some time to find, but there was no question of driver error (think Toyota) when parked vehicles erupted in flames in the middle of the night.

Buying the last model year of a vehicle design is usually a good choice; the problems in the original design have usually been found and fixed. My wife still has her 1995 Camry (design changed in 1996) and doesn't want to replace it. I replaced my 1989 Nissan pickup (design changed in 1990) a couple of years ago as a concession to arthritis, gettng a truck with power steering and an automatic transmission.

John
 
hippy

hippy

Ex-Staff (retired)
MartinM57 said:
I also note its at V1.0 - who buys (even if it's free) V1.0 of a software poduct?
Click to expand...
It's often said but I don't know how many really make a judgement on that and it's something of a fallacy that a 1.0 version will be bug-infested or shaky.

It's the nature of software and its complexity that there will be bugs and therefore bug fixes and incrementing versions, but it doesn't mean they were major bugs - if a perfect product were launched it would be 1.0 and stay forever at 1.0, presumably never ever selling !

Perhaps the moral is, include bugs in a product, or start numbering at 1.1 :)
 
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Marcwolf

Senior Member
Certainly is a most interesting idea and I can definately see the usefulness if one if working with projects that can have a lot of signals or intergrate a lot of different process modules.

Re the software version issue.
1. Is it mission critial or if it goes down will it seriously affect ones business if a bug is found
2. Does the user/owner use the software themselves or are they just looking for a niche market

With the first - I would wait for the first version to settle down (Op systems, process controllers etc)

With the second - I have more confidence re software that is used by the author and not just sold for a buck..

An personal example came to mind. Confronted with either paying $500 for Adobe Distiller, or writing a DLL front end for Ghostscript I went the Ghostscript way. I ended up with a COM interface that simulated the Adobe Distiller in 95% of the functionality. The lacking functionality was for functions that were very rarely used.
Several companies I dealt with had products that required the Adobe Distiller, so I offered my software to them. Event though I labeled it version 1 it was internally version 16.

Result - very happy customers and never an update needed. So it is still version 1 out there.

Take Care
Dave
 
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Marcwolf

Senior Member
Hi Folks

Just an update on this.. I downloaded the application, sacrificed an old printer cable and hooked this up onto my 20x2 running a very simple "Hello" program

Results are impressive. This app DOES work and works very well for a hobbiest.

My Program was this

Code: 
start:


sertxd("hello",10,13)
goto start
and I hooked Data0 and Data4 to the same output, ran the capture for 5 seconds, and then the analyser with ASYNC,9600,n,1

It can take some time to process very large rungs so be patient

the output is saved in the My Documents\ElmuSoft-LogicAnalyser directory although IE will pop up automatically

Here is a picture of an example

Take Care

Dave
 

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MartinM57

Moderator
Well done for getting it working. I'm trying not to be dim, but how do I see "Hello<CR><LF>" in the trace output?
 
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Marcwolf

Senior Member
Hi Martin

Ok - It was an example that one CAN monitor digital lines and see pulse chains. When working on issues re timing it can be very difficult to detect if pulse A is coming before pulse B.

For example.. We have an interrupt line and a serial line. The interrupt line must go high 10ms before the serial line so that the recieving PicAXE can jump to the interrupt routine to recieve the data.

However for some reason it is not happening. And your code looks fine.

So.. plug in this logic analyser onto the two lines and capture the information. When you examine it you find that the interrupt signal is not getting to the recieving Picaxe.. Upon checking you find a dry joint on the board..

Problem solved. Now without being able to see a representation of the pulses (and if you do not have a Oscilloscape) the chances of finding this is much more difficult. You may spend hours checking code, running test eamples, and even suspecting the recieving Picaxe (of sending one)

This is a simple but realistic example.

Dave
 
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MartinM57

Moderator
Ah - I thought you were trying to show that "Hello<CR><LF>" was actually coming out at whatever baud you thought it was and that the display somehow shows the hex equivalents of the decoded RS232 signals.

As a demonstrator that it can read logic 1's and 0's it goes some way I suppose - I'd like to see some high 0/pause 10/high 1 type code and the corresponding two channel display that shows how long the pause 10 actually took...
 
D

Dippy

Moderator
Dave: Absolutely. Just like I said in post#2.


I also assumed it would be displaying "Hello",cr,lf in hex.
So, if not, what exactly is it displaying?

If it is simply just to show logic levels then that's fine, but leave out the text and let the human interpret.
After all, if you display results then they should be correct results. Otherwise confusion prevails.

Are there any settings that need tweaking?

It certainly looks useful and very nearly very useful. Anyway, it's free and still handy as a simple display.
Do we know how accurate it is for timing?

Martin, can your Big Boy Tek do a similar thing? (but, obv, do it correctly).
 
D

Dippy

Moderator
Ah, Alec, it's amazing what parting with a few grand can do :)

Might be a good PIC/dsPIC project with GLCD.
 
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Marcwolf

Senior Member
I'll try and get back to doing some more testing today.. After Werewolf leg stilts, sterioscopic HUD test, Vrbot programming and testing...

Yep - its a busy weekend but I will get to it.

There are some 'tweeks' that I can do and I will try them

Take Care
Dave

p.s. My examples were on a 20x2 and it is the first time I have played with that chip
 
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Dippy

Moderator
That looks really nice, I'm tempted. IT would go nicely on a NEtbook.

Do any of the Big Boys do an equiv at similar price - it's nice to know that warranty and support will be available in 11 months time.
 
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graynomad

Senior Member
I've been using the "Logic" (as it's called) from Saleae for about six months now and I have to say it's fantastic. It's no HP, but for the sort of projects most of us get up to it does a very nice job, expecially for serial/SPI etc debugging. And it's only about $170.

It did have a bug in the software but downloading the latest version fixed that.
 
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