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Neet Studio

Thu Jun 07 2012, 03:35PM

Registered Member #4037 Joined: Fri Jul 29 2011, 03:13PM
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Posts: 86

I have actually used Mentor a long time ago so I am probably out of date. It wasn't that bad. The gesture shortcuts are handy to use. Also it is nice being able to do sequencing for massive naming/renaming selected bus rips/connector pins etc. on the schematic. I also like the way you can specify a bus routing rule by a tree notation. It beats the way we have to kludge the min max routing rules in Cadence.

Pretty much all the companies that I have worked for have a person/group that is in charge of the component library. Over the years, unfortunately part of (or all of) that task get pushed towards the engineers and the layout persons. The more difficult part is the process flow of forward/backward annotation/pushing to layout/routing rules etc.

I have used 4 or 5 packages for work, but only 2 packages for myself at home: old DOS EasyTrax and EagleCAD. At the pricing of commercial PCB packages and converting/migrating old designs etc, it is not something I would change as often as a lady changes her hair style/colour.

HV Enthusiast

Thu Jun 07 2012, 05:44PM

Registered Member #15 Joined: Thu Feb 02 2006, 01:11PM
Location:
Posts: 3068

Funny about the component librarian.

When i was at Lockheed, we had two librarians and unfortunately they were union.

Because everytime you submitted a part request to have a symbol / geometry made for say a 1/4W resistor, instead of making generic resistor part of that family, they would make individual symbols / geometries for whatever values you had.

So i had a schematic with 100 different valued resistors - all the identical family, they would literally spend two weeks making 100 individual parts. This happened for decades i hear until management forced them to cut costs and eventually laid them off and let the designers to library tasks.

Steve -

I presently have a couple seats of Eagle 5.1. Do you think its worth upgrading to Version 6 from your experience?

Thanks
Dan

rp181

Thu Jun 07 2012, 06:08PM

Registered Member #1062 Joined: Tue Oct 16 2007, 02:01AM
Location:
Posts: 1529

Basic day to day things that are not in EagleCAD GUI:
measurement tool for distances between objects (or vertexes) - pretty useful for checking high voltage safety. etc
measurement for track lengths - pretty useful if you have to figure the delay skews.

Layout:
import gerber files into a layout. Let's say an easy example: a PCB antenna reference design in gerber that the vendor provided for an RF ID tag. You can either import that into the layout program or hand draw it in EagleCAD layout. :P

High end stuff: (stuff that even the big guys don't always get it right)
hierarchical design - let say you are building a PCB for a big robot, you want to define the stepper motor driver circuit as a high level "component" once with its own symbol and "pinouts". You can then use that symbol as if it were a component elsewhere in the same design.

Eagle 6.2 allows for measurements between objects, as well as trace length matching, meanders, and differential routing. The new eagle also allows you to import other designs. In your example, you would save the stepper controller and associated layout as a separate design, and "paste from" into the the main schematic as many times as you need it. The schematic and board layout are brought in. This implementation is actually very similar to building assemblies in CAD software, so I like it. Your right about the importing Gerber files though, that would be useful (though I can understand why it was left out, as gerber files don't specify components).

I have had no issues with stability in 6.2, and it really is useful when doing parallel designs and differential signaling. The dimension feature is useful too, no more manually typing all of that in.

Nicko

Thu Jun 07 2012, 08:32PM

Registered Member #1334 Joined: Tue Feb 19 2008, 04:37PM
Location: Nr. London, UK
Posts: 615

rp181 wrote ...
The dimension feature is useful too, no more manually typing all of that in.

I'm sure there always used to be a dimensioning ULP - even back in the 4.x days

Neet Studio

Thu Jun 07 2012, 09:18PM

Registered Member #4037 Joined: Fri Jul 29 2011, 03:13PM
Location:
Posts: 86

>In your example, you would save the stepper controller and associated layout as a separate design, and "paste from" into the the main schematic as many times as you need it.

Not that I don't want to be able to import design either, but you are still working with a flat design with copying & pasting.

In a heirarchical design, you only need to modify that "component" once as there is only 1 copy and the program would take care of the changes to each of the instances. It is very natural thing to do in a programming language or a HDL. Unfortunately, I have yet to seen an implementation stable/smooth enough for any of the projects to take full advantage of that other than using them as a subblock.

I guess I got to try out 6.2 one of these days.

Steve Conner

Thu Jun 07 2012, 10:17PM

Registered Member #30 Joined: Fri Feb 03 2006, 10:52AM
Location: Glasgow, Scotland
Posts: 6706

Granted, Eagle has no support for concurrent workflow (several people working on the same design at once) or hierarchical schematics. The solution is not to use it on any project so big that you need these features.

We use Subversion for version control, and we also store our Eagle files in there. But concurrent working still isn't possible. The Eagle files are all in a proprietary binary format, so Subversion doesn't know how to merge concurrent changes, and Eagle itself certainly doesn't.

So, in spite of the version control, when you're working on an Eagle design, you have to make sure everyone is done with it and "take ownership".

I haven't tried Eagle 6.x yet.

Nicko

Fri Jun 08 2012, 05:12AM

Registered Member #1334 Joined: Tue Feb 19 2008, 04:37PM
Location: Nr. London, UK
Posts: 615

Steve Conner wrote ...
The Eagle files are all in a proprietary binary format, so Subversion doesn't know how to merge concurrent changes, and Eagle itself certainly doesn't.

Eagle V6 files are all XML.

Neet Studio

Fri Jun 08 2012, 02:15PM

Registered Member #4037 Joined: Fri Jul 29 2011, 03:13PM
Location:
Posts: 86

Until Eagle CAD's new format has became a standard for everyone in the CAD world use that, it is propriety by definition. ;)

XML is just a tagged structured file format written for people that don't know about reading file formats on their own without using some frameworks or libraries. It is not a magical replacement for documentation for the data structure. :P

Some well documented formats such as DXF on the other hand was there well before XML and still works reasonably well across different packages and became De facto standards.

Nicko

Fri Jun 08 2012, 02:51PM

Registered Member #1334 Joined: Tue Feb 19 2008, 04:37PM
Location: Nr. London, UK
Posts: 615

Neet Studio wrote ...
XML is just a tagged structured file format written for people that don't know about reading file formats on their own without using some frameworks or libraries. It is not a magical replacement for documentation for the data structure.

That's just plain rubbish. XML is an extensible validatable markup format, no more than that - nobody pretends otherwise. In Eagle's case, the tags used are documented in the DTD which is part of the V6.x installation - its an "open" format in that they document its structure, the tags used and their meanings - what more do you want?

As the format is documented you can write Eagle files from other applications should you wish and also write import/expert tools to/from other formats.

You mentioned DXF as being a "de facto" standard - maybe amongst those exchanging Autocad documents it is - its a common format, but there a dozens of variants of it, and interoperability is often not as easy as you might expect, especially as the newer functionality that Autocad have introduced in recent years is either not documented or is unsupported in DXF.

Neet Studio

Fri Jun 08 2012, 05:19PM

Registered Member #4037 Joined: Fri Jul 29 2011, 03:13PM
Location:
Posts: 86

It is propriety because it doesn't follow any existing established standards by definition. The CAD world really have no standards as each program does its own thing and may change between revision.

What xkcd thinks of standards :)

Until other CAD programs start allowing import/exporting EagleCAD's format, it is propriety. Even then at best, it is a De facto standard. As you have pointed out, even that is a wash.

>what more do you want?

Just pointing out that XML is not required to have a documented format that others can use. The XML format only makes it easier for others to use pre-written packages/framework/library. Even before XML people knew how to import/export files for documented formats. Binary data is still data. No more no less.

The only new part is they have finally starting to document their format. That should be the emphasis, not because it is XML.

No need to get mad at me for pointing out the obvious.

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