[How do I?] Oscilloscopes & Logic Analyzers

That's some rant you got there, mws.

Being from the same era (trained in radio & TV electronics during the late 1970's), I've seen how "everything" has gone digital without these designers understanding that the real world is analog!

On top of that, like your drone example, everything has become too many layers. The tablet and its OS are supplied by one company, the drone hardware built by another, the software is a modified version of a freeware app written in a language that was developed by a college student last year....

Call me old-school, but I love gear-change lathes and reading the scale next to my hand. I like to feel the cutting action as I turn the wheel. My 2013 daily driver is a stick shift too!

You guys can keep your DRO's and the constant fiddling they need to stay calibrated, zeroed or just plain operational.

I'm happy living in the analog world.
 
This might be a little off topic, but going with what has been said, I miss owning an analog multi-meter and picked up a Simpson 260 the other day for under $40. Back in the day, this was the meter you had to have, but it was always out of my price range. Always had a dinky Radio Shack one to use. Kick myself for giving it to one of my nephews after dad pass away!
 
:grin big: WARNING: Long, tedious reply to follow... LOL :grin big:
On some respects, I agree with you Mark, on others, I don't have the knowledge and/or background to agree or disagree.
I know my cell phone service is worse since they went digital all the time touting how much better it was going be. All the while knowing it wouldn't just made it more profitable being able to route more data and calls through the same infrastructure.
As far as my interest goes, I've been intrigued with open source electronic options like Arduino and Rasberry Pi. They have their limitations (for now), but it does allow a means for backyard inventors/tinkerers to enter the digital age/market on the cheap. I see more and better inovation coming from the small guys and gals out there than most anything coming from Corperate America these days. Once proven, they are more than happy to come steal it with big time lawyers and loopholes, but I can see a day coming where that will end as well.
As a new hobbyist in the metalworking field, I like learning on the manual machines I have, but with the limited time I have to play, having a DRO to help me track position and not lose count of turns is a big plus.
I chose going with Yuriy's Touch DRO simply for cost. I end up with a 3 axis DRO on my mill and a 2 axis on the lathe for less than half the price of a single dedicated 3 axis kit from places like DROPRO's. The smaller scales are much easier to fit and mount as well.
I don't need a wireless display, but don't know enough about them to match a dedicated display. With the wireless connection to my tablet and/or smart phone, I can use either with my mill or lathe. I can update software simply by a touch of a button so to speak. A display is easily replaced as well with a new tablet or phone just by downloading the App. Fuctionality is also being added all the time. When I first ran into it, the Touch DRO was fairly basic. It now has a fully funtional and customizable toolbox for your various tooling that can be updated easily. They've also added a Tach option though it's currently in the infancy stage of developement.
Memory space is only limited by the amount of expansion memory your device can handle. My tablet, for instance, can handle a 32 Gig flash card on top of the 16 Gig internal memory. Something not possible with any of the dedicated DRO system I've seen. Having the mobile display will also allow me to look at saved steps for projects and change/improve them anytime anywhere.
I know it's not the best DRO or scales out there, but with the large following and open source software and hardware, it may well be the best one out there in the future.
The main reason I went with the Arduino vs MSP was simply the fact I've wanted to learn to use it for other projects and ideas I have. Seemed like a sensible thing at the time just didn't know that the new iGaging Absolute scales I bought were not compatible with the system as it currently sits.
The amin issdue, as I see it, is that most of those using it have the older scales and aren't currently interested in making the new Absolute scales compatible. I figured why not get an oscilloscope or logic analyzer to connect to my scales and get the data needed for the changes needed for the hardware and programming. From what I've read, there are plenty of people out there in the Arduino community quite willing to help with this, but seems none are willing to spend the money on the scales to do the hack.
I posed the question here because I know basically nothing about O'scopes or Logic Analyzers, but knew from my time on this forum that there were many such as yourself, who do have the knowledge and are more than willing to share/teach people like me.
In another thread (http://www.hobby-machinist.com/threads/does-it-exists-3-axis-display-4-igaging-dro.37555/page-2), I posted this that I found about the compatibility of the new iGaging Absolute DRO scales:
Is the Android DRO compatible with the serial output of the new igaging "ABSOLUTE" series ? : http://www.igagingstore.com/38-Absolute-Digital-Readout-DRO-Stainless-Steel-S-p/205483.htm
Reply
Replies
Yuriy KrushelnytskiyAugust 3, 2014 at 9:45 PM
I don't know; haven't had a chance to play with the new model.

Nathan WrightNovember 18, 2014 at 10:07 PM
Short answer: no.
At a minimum, the Absolute DRO has a 2KHz clock. But, changing the clock freq isn't enough.
The data line is severely attenuated with a 5.6K PD resistor. The original display unit has a 100K PU resistor, so this will require a schematic change to match.
Have not had a chance to look at the data on the logic analyzer to confirm if it is still 21-bit.
(There also appears to be a pull up on pin 4 of the Mini-USB. Looks to be a basic connection check - the control unit stops sending the clock if that pull up is removed. Looks like this can be ignored.)
Will investigate further and post an update as time permits.

All this may mean something to you, but to me it just says the scales I bought and installed won't work for the DRO I hoped to have and the Arduino PLC's and various electronic components I bought will sit on the shelf until someone does figure it out.
WHEW !!!
 
I think you guys are missing the point about the wireless display. It is not about the wireless but about the display.

Sure Yuri could have opted to design his own electronics to interface to the scales and provide a display, but then you need to build a way more complicated electronic design and an enclosure for it all. Then the software project becomes much bigger, support for your interface (buttons) need to be done and a software layer for the user interface (either seven segment led or full graphic screen).

Instead of doing all that I am sure Yuri considered that there are many andriod devices out there that are sitting around unused after being replaced by current generation ones. These devices have the CPU capability to perform a DRO fronted very nicely. They all have touch screens so user input is easy to integrate and most importantly they have an excellent graphics stack and operating system to make the software development easier. The only hard part was interfacing an android device to the scales. Here using Bluetooth made sense as this is very simple to integrate since the Bluetooth module just presents itself as a serial port to the android software. The fact that it is wireless is just an added bonus.

Sent from my GT-I9505 using Tapatalk
 
atunguyd said:
I think you guys are missing the point about the wireless display. It is not about the wireless but about the display.
Click to expand...

I agree with most of what you said, but I think you can use the App wirelessly or direct from USB plug which ever you want as far as I know.
I think Yuriy went with the App route simply because it's easier, cheaper, and able to be easily modified and kids today are all in to App's. Not tometion, a whole lot easier to market since it's a free. open source item.
I'm certain he went with Android simply due to the fact that Apple has such a strangle hold on what they allow and unless you use Linux, Apple or Android are about it for formats.

As far as this thread, I was looking to learn something and expand my horizons. I haven't used an O'scope or Logic Anaalyzer and wanted input from those that had.
It would be easier to sit back and wait or someone else to figure out the scale problem, it will eventually happen or change scales to something that will work, but then I have a few hundred dollars of scales to put on the shelf or try and sell. I'm also under the impression that the Absolute scales are a better version of the older ones.
 
I would love to help. I am sure I have the expertise to reverse engineer the new igaging scales. My problem is sourcing one to do this.
I have already rewritten the arduino code to use a RTOS and nested interrupts to support all the other scales.

Sent from my GT-I9505 using Tapatalk
 
At some level, I'd almost prefer either sending you a scale or reimbersing you to save me the time and trouble.
 
Yeah mate the problem is that I am about 10000km from you.

Sent from my GT-I9505 using Tapatalk
 
atunguyd said:
I think you guys are missing the point about the wireless display. It is not about the wireless but about the display.
Click to expand...

I'm not hung up so much on the remote as I am about all the layers involved. Indeed, you're right about Androids being re-purposed lends a lot of power to an application where dedicated DROs are limited. But it sounds like you have more detailed knowledge on the specifics of JPiggs problem.

From what I was able to determine (the sales-pitchy web site was a little thin on technical details for me) I had the impression that these particular iGaging scales had a remote display that lacked any data port (USB or otherwise) making them incompatible with that method of data collection. But from your post, you specifically mention pull down resistors on data lines and word-lengths, inferring it does indeed have a data port.

In reviewing Yuriy's pages, it appears that the data display can be eliminated, leaving you with a quadrature output from a 3.3 volt level scale. This would require data collection using the MSP430 controller.

It's all a little confusing to me and THIS is where I get frustrated with the way folks approach technology today. I'm used to having clear, concisely listed specifications for things. It seems real specs don't mean as much today and made up metrics have become commonly accepted, since they describe functionality which people think they understand. Acronyms make me crazy, like everyone is supposed to know them. Like SCP port, which apparently these iGagaing scales use. I know it's a serial data and control scheme but I'll be damned if I can find any specifications for it.

I suppose that technology is moving faster than I can keep track of, but lately I have seen the wheel being reinvented because just haven't taken the time to research what already was. Now I am ranting.

But to the original question: If your getting into the nitty-gritty of electronic control circuitry buy a decent scope and you'll open new doors. I'm also intrigued by some of the scope interfaces I've seen that use your laptop/Droid/etc for all the display, memory and control functions. The interface is just a digitally controlled analog to digital converter. I mean, as long as we're using our Droids to do stuff... :) But I do like the Rigol stuff I've seen. There's even a hack for one that allows the speed of it's A/D input to be increased to the next higher model.

I'm interested to see what you find out in any event. Keep us posted please.


4GSR: I have dozens of multi-meters, digital and analog, from Cheap chinese no names to high and Flukes and Racal-Dana. The 260 (of which I have a few now) is my first and favorite go-to meter for most everything.
 
Last edited:
You must log in or register to reply here.
Back
Top