Cheap Logic Analyzer (Home Made)

Hi all,

I have fount that page and want to share with people on the forum.
Since Logic Analyzer look to be a good way to solve problem.

f6fbb.org/LogicAnalyzer/index.html

If someone better than me (easy) can look at the specs and tell if it’s usable
for Us, should be helpfull.

Have a good day.

“If it’s good, i will build one for me. and maybe for others”

It may be able to help with certain things. I for sure would not use it to replace mine by saleae. The DIY version you mention has a max of under 4K of samples and I believe a max of 5mhz. The speed is fast enough for several different things and if you can setup your triggers properly you may be able to capture what you are looking for. But even at it’s lowest speed, I think it can only capture up to maybe a second of data…

I most often use mine in a very lazy way. I simply startup and know that I can capture easily capture 10-15 seconds or more. Example Mine is set for 4mhz and 50M samples. I used that yesterday to find out that my new C library code for HSERVOSTATE was corrupting the servo outputs (Forgot to reset the IO pins associated TimerZ0/Z1 to be controlled by the timer after the cycle of grabbing Analog data…

Awhile ago I wrote a quick data capture program for the BAP that also allowed you to capture data like this, but I never did much of a back end for it.

Kurt

So probably not a so good idea… :unamused:

There is 2 kit on Sparkfun

One OpenSource:
sparkfun.com/products/9857
69,92$ (no casing, no probe… etc)

On All made:
sparkfun.com/products/8938
149,95$ (Look to have all you need)

Or probably the one you have[size=150] ““EDIT”” Yes… that’s the one you have… “”"[/size]. But i was looking for something cheap… LOL
So will probably pass for now.

Yep I have the second one. The first one looks like it might work pretty well. You might look around more for others that use the open source software… One of the comments up on sparkfun mentioned why buy it here when you can get it for $10-$20 cheaper elsewhere…

As to pass on the first one you mentioned. That depends. If you can actually build it for lets say $25 it will beat not having anything! As I mentioned in the first post, you can do a lot with careful use of triggers. Example not sure if some serial is working properly. Simply add something like a high command to some other IO line just before it and use this pin as a trigger… I do this from time to time still. When before all I had was the parallax usb oscilloscope thingy… parallax.com/Store/Education … fault.aspx, it also was very limited on what it could capture and I used that approach often…

Kurt

Quick update on this: I see you can order the same one or similar one as the Sparkfun 1st one you mentioned from Seeedstudio… seeedstudio.com/depot/preord … l?cPath=75
Price: $60, but I believe it would ship direct from China…

Kurt

Tanks a lot…
And Free shipping for order over 50$
They have the probe too for 6$

Ok… i have a iPod… and i have made a quick search… found that…

itunes.apple.com/fr/app/oscilloscope/id388636804?mt=8
oscilloscopeapp.com/

It use the audio jack … is it workable for PPM like signal ?

I have no idea. Can’t read the specs, it is in some foreign language :laughing:

But you can also probably hack together some code for one of your controllers to do a poor version. For example the Society of Robots (SOR) site with the Axon2 (ATMEGA 640), he has sample code that you can download and one is a scope program… Would probably not be hard to modify for other Atmega 640/1280 type controllers…

Kurt

Got specs from a probe supplier:
hmb-tec.de/HMB-TEC/Scope_Cable.html

Features und Technical Data:

1.Option for iPhone, iPad or ipod touch
2. Connection to headphone jack 4-pin connector
3.special protective circuit to protect the highly sensitive input
4.compatible with many Audio-/Scope-Anwendungen from AppStore
5.quality oscilloscope Modulartastkopf for iPhone / iPod oscilloscope applications
6.4-pin plug fits iPhone and iPod Touch, iPad
7.Cable length 1.2 m
8.Compatible with iPod Touch, iPhone and iPad (IOS 3.x and 4.x iOS)
9.compatible with all Audio-scope applications that are used for iPod touch (2G) and iPhone (from 3G) available in AppStore (oscilloscope, Oscilloscope, Spectrum, SignalScope …)
10.Input voltage up to 50Volt (Vpp)
11.Switching 1:1 and 1:10

good music…

Sorry to post a lot of different things… but i want to share what i found…!

cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=120692375760&fromMakeTrack=true&ssPageName=VIP:watchlink:top:en

@ Kurte:
What do you think of that… ?
robotshop.com/ca/content/PDF/datasheet-tol131b2p.pdf

Ok… I do put a lot of thing and link here…
Sorry again.

I will try the ipod…
Just ordered 2 things (will have tomorrow:

robotshop.com/ca/seeedstudio-trs-to-bnc-probe-adaptor.html
robotshop.com/ca/seeedstudio-dual-probe-for-dso-nano.html

and i already have a scope probe to test.

Also… I have found an app for ipod witch generate PPM signal for use in RC.
I have hook it to my JR transmitter (Trainer port) and it does work… !

itunes.apple.com/us/app/flypad-fly-your-rc-plane-your/id375967752?mt=8

At least i have a PPM sample… witch is on the same device i try to use to look at that sample… Damn…
Oh… my wife have another ipod… LOL…

So generate from an ipod… to another ipod… interesting…

I have made a little test with FlyPad and a oscilloscope.

I am not realy good at trigering my signal… :frowning:

I have also made a test from iPod to iPod oscilloscope. Sending a waveform to another ipod.
Look like it work, even try FlyPad to a iPod and it does work… trigering problem again… lol

No video since using the 2 ipod left me no camera… LOL

Ok… after all that… just ordered a LogicAnalyzer…

I have ordered that one:
cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=290541562610&ssPageName=STRK:MEWNX:IT

Hope it will work ok

Also look a that
Hack
iteadstudio.com/copied/hack-a-saleae-logic-analyzer/

I will keep people informed if it work good… since it’s so cheap

Hope it works out for you.

Personally it does give me indigestion as it is a counterfeit and it uses software from another company (Saleae.com) that they have spent lots of time and energy to create…

Kurt

Don’t know if it use that software.

You make me shy of my descision now :frowning:

Ok…

I have already ordered from eBay…
Can i use that board for something else… !

I will buy the saleae logic analyzer…

You guys have made me very shy… :blush:

Ok… did i say that the Saleae was expensive…!
usbee.com/

Look like a bargain when compared to this one…!

Save by eBay:

Since the eBay listing was removed my ebay… i ain’t hear about the seller since today…

And yes Kurte… it’s a “Logic” clone… :frowning:
He sent me a download link to a “Logic” software.

Sorry…