Designing Custom Shield for MEGA2560

[iwoloschin]

I'm trying to design a custom shield for a MEGA2560.  Without going into details, I'm trying to make a number of power measurements and log everything to either a computer via serial or a locally mounted SD Card.  I'm trying to find a good schematic/layout of a basic MEGA shield, essentially the board dimensions and headers.  Unfortunately this is not a "Non-Profit" project, so I don't think I can use Eagle, instead I'm trying to use ExpressPCB at the moment.  Has anyone released a basic MEGA shield for ExpressPCB?  If not, what would be the best way to create my own?  I'm guessing I'd need to install Eagle and copy down all of the measurements myself and design my own template in ExpressPCB?  Alternatively, is there a better program to be using?  I'm not willing to pay for anything just yet, but something that allows for some sort of trial period would be acceptable.

Thanks!

[mmcp42]

EAGLE is free up to a certain board size 3" by 4" if I remember correctly
certainly big enough for a shield (unless it "hangs over the edges" a lot!)

ah just saw your not "not for profit" - oops

[iwoloschin]

EAGLE is free up to a certain board size 3" by 4" if I remember correctly
certainly big enough for a shield (unless it "hangs over the edges" a lot!)

ah just saw your not "not for profit" - oops

That's the kicker.  I did find that I can use Eagle for "evaluation" and while this project isn't going to directly make any money, I am using it as part of an internal R&D effort, which means it's probably easier to just avoid Eagle if I can.

I did see some mention of KiCAD and that look nice, but I'm not sure if that's something I should continue looking at.  Does anyone here use anything other than Eagle? :p

[CrossRoads]

"Does anyone here use anything other than Eagle?"
Oh, that's opening a big can of worms!!

A while ago (in the old forum I think), someone posted an expressPCB layout for shields. I have it at home and can post a link in a few hours.
Might be worthwhile paying for a minimal eagle license ($250?) and then be able to use all the surface  mount footprints that are available.

[Senso]

The cheapest eagle fee is 50$ to use it in commercial projects, so that might be the sale of half a dozen of shields or even less..

[CrossRoads]

Here's the expresspcb files

http://www.crossroadsfencing.com/arduino_shield.sch
http://www.crossroadsfencing.com/arduino_shield.pcb

[iwoloschin]

The cheapest eagle fee is 50$ to use it in commercial projects, so that might be the sale of half a dozen of shields or even less..

Yes, but I'm not planning on selling anything directly.  My company has no interest in that business, this is for an "Internal R&D" project.  I may give Eagle a shot, it's just easier if I don't have to write up an expense report.

CrossRoads,

Thanks, I'll take a look at those in a little bit.

[bubulindo]

Doesn't internal R&D qualify Eagle to be used? You're not making money out of it and if eventually goes into production, you can always buy the Eagle license.

[liudr]

That is what I have. Is there any reason you have to cover the MEGA with a large shield? If you design one that is smaller and also fits uno then you can use uno also. Kind of flexible that way unless you need more pins.

The cheapest eagle fee is 50$ to use it in commercial projects, so that might be the sale of half a dozen of shields or even less..

[iwoloschin]

At the moment I believe I need to use more than 6 analog inputs, unless I multiplex them myself, and I'd really rather not have to add that complexity into my design.  Additionally, I'd rather the more powerful Arduino for any future projects that pop up.  Also, this is simply a "quick" proof of concept, it's not a production design, so I can afford to be overkill, and then pair down if I need to bring this to a production design.

[Jeff K]

Have you looked into the Freemium version of Eagle?  I believe it gives you a 60 day trial commercial license.  Usually when you install Eagle (the newer versions) it will allow you to submit your email for the Freemium license key.  If you already have it installed as a freeware version, I think you can get the Freemium license from one of the "About" or "Help" menu options.

[TonyD]

Doesn't internal R&D qualify Eagle to be used? You're not making money out of it and if eventually goes into production, you can always buy the Eagle license.

I don't think so. Doing internal R&D in a business is still a commercial activity even if you're not making any profit from it, so its not keeping with the spirit of the free license.

Try DesignSpark PCB or KiCAD If you want a free PCB package.

[Graynomad]

Does anyone here use anything other than Eagle?

Yep, all those with a low pain threshold

______
Rob

[skyjumper]

This is a very powerful and completely free package:

http://www.gpleda.org/index.html