How are *official* schematics presented?

[Robert Latest]

Just tried a simple A-size...

PDF = 42KB

PNG = 102KB

For the _same_resolution_

The size of a PDF (as pure vector graphics without embedded pixmaps) doesn't
depend on resolution. Or, expressed differently, resoultion of the output
device is an alien concept to vector graphics.

robert

 

[Robert Latest]

Methinks it could be the PDF conversion in OpenOffice that bloats it.

As long as we're talking about Eagle; no, it's the crappy PS export that
does it. I've looked into the generated postscript: Each and every line in
your schematics (and that includes all those little bits of the vector
fonts) is not only drawn as a line, but also as a box around that line.

Interestingly the CAM processor does a somewhat better job (on schematics as
well).

Someone also wrote a eagle2ps ULP script avaliable from CadSoft's download
section.

Thought it might be due to the schematic being mostly analog parts. But
so are yours I guess so I'll have to look into the file size thing some
more.

Be aware of the fundamental difference between vector graphics (PS,
PDF), raster graphics (TIFF, GIF, PNG) and lossily compressed raster
graphics (JPEG) as well as the fact that both PS and PDF can contain
embedded raster graphics (like when trying to make a PDF from a TIFF). On
top of that, TIFF is only a container format that can embedded data
compressed in one of several ways, including no compression at all.

Schematics are, by their very nature, vector graphics (including fonts,
which are also vector graphics), so a good postscript exporter (which Eagle
doesn't have) would make an excellent job of them. On the other hand,
schematics are also 99.9% empty white space, which is why they compress
excellently when treated as raster graphics.

robert

 

[Robert Latest]

Aha! I guess OpenOffice needs to fix its OpenOrifice ;-)

No, the problem was the PS from which the PDF was created. Unless you made
the PDF from a raster image, which is always inferior.

robert

 

[Robert Latest]

sometimes wishes are declined, such as mine for hierarchical sheet
structures. A rather serious shortcoming IMHO but they are of different
opinion.

Oh, they actually have a different opinion? That's be interesting to hear.
What I don't like is how they handle nets that go across several sheets --
just with labels things can go horribly wrong. We'd need those tags that
really stay attached to their nets, with the text actually being the name of
the net to which they're attached.

Also, this SW is quite open. There is fully documented user language
programming and scripting. So if you need something unorthodox to happen
you can write a kolstad.ulp routine and it'll do that.

Yes, just yesterday I noticed that on a four-page schematic I was working
on I had somehow managed to get completely unrelated nets connected
together. A script hacked up in 10 minutes that listed all nets that had
several disjoint and unlabeled sections took care of that.

robert

 

[joseph2k]

I do all my reports and design reviews using Adobe v4. Later versions
of Adobe are bloatware... so much so that they put M$oft to shame ;-)

MicroSim Schematics prints beautifully using (Adobe) PDFWriter,
slightly smaller files than the freebies. You can also insert
"pictures" into MicroSim Schematics.

Word also can use PDFWriter to make compact PDF's.

With Adobe v4 you can merge many different pages into a single
document, and "Save As" compacts.

/begin personal opinion/
OrCAD Capture is the biggest piece-a-crap on the face of the earth.
/end personal opinion/

...Jim Thompson

Mere user unfriendly, minimally useful, unreliable, and popular does not
quite get there.
For truly evil software you have to be required for the task, truly obtuse
to understand, never save any of ten or more separate required data entries
per run, and then when the user makes an error fails destructively to data
to previous successful executions. This class is called user vicious.

 

[Ian]

Yeah, it's probably not the best PDF converter and when zooming in things
like inductors begin to look fuzzy at the edges. Where did that good old
HPGL standard go? None of the new SW seems to understand that anymore.

MS Word will import them if you get the right filter, and change .hpgl
suffix to .hgl

Regards
Ian

 

[Joerg]

Joerg wrote:




As long as we're talking about Eagle; no, it's the crappy PS export that
does it. I've looked into the generated postscript: Each and every line in
your schematics (and that includes all those little bits of the vector
fonts) is not only drawn as a line, but also as a box around that line.

Interestingly the CAM processor does a somewhat better job (on schematics as
well).

Someone also wrote a eagle2ps ULP script avaliable from CadSoft's download
section.

Thanks. That is a good hint. Got to try that.

Be aware of the fundamental difference between vector graphics (PS,
PDF), raster graphics (TIFF, GIF, PNG) and lossily compressed raster
graphics (JPEG) as well as the fact that both PS and PDF can contain
embedded raster graphics (like when trying to make a PDF from a TIFF). On
top of that, TIFF is only a container format that can embedded data
compressed in one of several ways, including no compression at all.

Schematics are, by their very nature, vector graphics (including fonts,
which are also vector graphics), so a good postscript exporter (which Eagle
doesn't have) would make an excellent job of them. On the other hand,
schematics are also 99.9% empty white space, which is why they compress
excellently when treated as raster graphics.

In some formats (PNG and TIFF) Eagle does produce really small files
that are excellent for a client who wants to create a large printout for
lab bench work.

 

[Joel Kolstad]

This is one of the reasons I switched to Cadsoft. They run several
newsgroups (real ones, accessible via this here newsreader...). Employees of
that company actually come online for help, take suggestions and they even
run separate suggestion NGs in at least two languages. And they do listen.
Best of all, after we all sent in our electronic "Dear Santa" letters quite
a few of the suggestions have either already made it into new releases or
are now on the roadmap for the next release.

That is impressive. I use Pulsonix when I can and ORCAD/PADS when I have t;
I don't bother trying to get Cadence or Mentor to fix anything in their
software anymore -- it just isn't worth the effort. Pulsonix is pretty good
about fixing bugs and adding features... I was reading through the release
notes for their latest version (4.5) last night when I realized, "Hey...
there's actually a *lot* here that I had specifically asked for!" And while
I'm sure I often wasn't the only person asking for various features, their
response is still impressive.

Probably just to tick me off they also went and killed pretty much all the
bugs I had found and posted to the Yahoo! support group. They did add a few
new ones in the process, but overall it's becoming a really nice package
they've already fixed a couple of the new ones. They don't seem quite as
"communicative" as you suggest Cadsoft is -- only on infrequent occasion will
they post to the Yahoo! group, and almost always under an anonymous "Pulsonix
Support" alias, but it appears they read pretty much everything that goes on
there.

The only "big" feature I think they're missing relative to Eagle is a
scripting language. Many people, including Pulsonix's biggest cheerleader,
Leon Heller, have asked for it, so I imagine will show up someday. Pulsonix
is a heavy user of the Microsoft .Net "technologies," so unfortunately I doubt
it'll ever show up in Macs or Linux as Eagle does.

I'd probably have taken a serious look at Eagle when I found Pulsonix if it
hadn't been that I wanted a SPICE package as well: Pulsonix bundles SI-Metrix
as their SPICE engine, which I had been favorably impressed with back in grad
school.

---Joel

 

[Joerg]

Joerg wrote:




Oh, they actually have a different opinion? That's be interesting to hear.
What I don't like is how they handle nets that go across several sheets --
just with labels things can go horribly wrong. We'd need those tags that
really stay attached to their nets, with the text actually being the name of
the net to which they're attached.




Yes, just yesterday I noticed that on a four-page schematic I was working
on I had somehow managed to get completely unrelated nets connected
together. A script hacked up in 10 minutes that listed all nets that had
several disjoint and unlabeled sections took care of that.

Other times Eagle is overly "complainatory". On the design I finished on
Tuesday it flagged errors because I had connected VCC, VDD and V+. Had
to, because of various inherent power pin names in the chips I used.
When disconnecting, of course, it flagged missing connections. AFAIK the
only way to cure that at present is to "invoke", making power pins
visible, and then conecting them with a minimum piece of wire. Doesn't
look good on a busy schematic.

Oh well, since I don't do layouts and they are done on another system
anyhow I have the luxury of being able to ignore error messages

 

[Joerg]

That is impressive. I use Pulsonix when I can and ORCAD/PADS when I have t;
I don't bother trying to get Cadence or Mentor to fix anything in their
software anymore -- it just isn't worth the effort. Pulsonix is pretty good
about fixing bugs and adding features... I was reading through the release
notes for their latest version (4.5) last night when I realized, "Hey...
there's actually a *lot* here that I had specifically asked for!" And while
I'm sure I often wasn't the only person asking for various features, their
response is still impressive.

Probably just to tick me off they also went and killed pretty much all the
bugs I had found and posted to the Yahoo! support group. They did add a few
new ones in the process, but overall it's becoming a really nice package
they've already fixed a couple of the new ones. They don't seem quite as
"communicative" as you suggest Cadsoft is -- only on infrequent occasion will
they post to the Yahoo! group, and almost always under an anonymous "Pulsonix
Support" alias, but it appears they read pretty much everything that goes on
there.

The only "big" feature I think they're missing relative to Eagle is a
scripting language. Many people, including Pulsonix's biggest cheerleader,
Leon Heller, have asked for it, so I imagine will show up someday. Pulsonix
is a heavy user of the Microsoft .Net "technologies," so unfortunately I doubt
it'll ever show up in Macs or Linux as Eagle does.

I'd probably have taken a serious look at Eagle when I found Pulsonix if it
hadn't been that I wanted a SPICE package as well: Pulsonix bundles SI-Metrix
as their SPICE engine, which I had been favorably impressed with back in grad
school.

No direct SPICE link. OTOH I didn't have that with OrCAD (DOS) either.
My work is mostly analog and there, quite frankly, SPICE often doesn't
cut it. Correctly modeling a non-ideal RF transformer, noise in a laser
module, ultrasound transducer behavior and stuff like that would take
much longer to do than rigging it all up in the lab and having a look.
That's what we are going to do again on Monday ;-)

 

[Joerg]

MS Word will import them if you get the right filter, and change .hpgl
suffix to .hgl

That's how I did that in the early 90's. OrCad SDT and Word for DOS. But
now? Eagle doesn't even have a native HPGL output format :-(

Maybe it's not needed much anymore. One of the main reasons were early
laser printers. My first one could not take more than 1MB in additional
memory and even that cost a bundle. Barely enough for a dense schematic.
But since it was an HP it understood HPGL perfectly well and printed
marvelous schematics from that. The newest printer here in the office
has oodles of memory. It can store a big fat stack of pages and print it
all out later.

 

[Joerg]

Joerg wrote:




That is just a quirk of the Eagle export module.




Of course. It's been standard for some 15 years now and has pretty much
replaced GIF.

Perfect! Then that's really all I need for sending an extra copy of the
schematic. I've seen one that I had sent a long time ago when visiting a
client. They had printed it out for the lab, the size of wallpaper.
Crisp sharp lines, no fuzzy edges anywhere.

 

[Joel Kolstad]

No direct SPICE link. OTOH I didn't have that with OrCAD (DOS) either. My
work is mostly analog and there, quite frankly, SPICE often doesn't cut it.

I'm sure you might feel differently if you could build an LM324 out of
discrete transistors for less than the cost of buying one pre-packaged.

And I suspect you might have tried, at some point.



In general there's a balance to how much SPICEing vs. bench testing one would
do to maximize productivity, I think. I wouldn't want to try to build noise
models for lasers either! ...yet clearly it wouldn't make sense for Jim to go
and build his amplifiers out of discrete parts anymore.

---Joel

 

[Joerg]

I'm sure you might feel differently if you could build an LM324 out of
discrete transistors for less than the cost of buying one pre-packaged.

And I suspect you might have tried, at some point.

Oh yeah! But mostly that was when I needed less than what an opamp
contains or when I couldn't make good use of the remaining three
sections, in which case even a LM324 does get expensive. The single and
dual packs aren't always that economical. Sometimes a lone transistor
can do the job.

In general there's a balance to how much SPICEing vs. bench testing one would
do to maximize productivity, I think. I wouldn't want to try to build noise
models for lasers either! ...yet clearly it wouldn't make sense for Jim to go
and build his amplifiers out of discrete parts anymore.

True. For chip designs we have used SPICE and other sims to the point
where once a Pentium (the first version) blew out. We smoked it.

 

[qrk]

Indeed. Tried it with the project I finished yesterday. It's sent to the
client already so too late this time but when I stored it in PNG the
schematic shrank from about 1MB for 84K. Is PNG widespread and commonly
readable? I can read it but that doesn't have to mean anyone can.

WRT the original topic I now must confess that I am beginning to warm up
to the idea of writing 33K2 like many Europeans do instead of 33.2K, or
33R2 instead of just 33.2. When tired at the end of the day it's easy to
overlook one of those decimal points. I gave the schematic one more
thorough visual and thought I'd bunged it with one resistor, until I saw
that little dot and knew it was ok.

PNG is pretty widely accepted. Most modern image viewers handle PNG.
Web browsers handle PNG. Microsoft Word 2000 and OpenOffice handle
PNG.

Joerg, If you want to print your schematics to PDF, get a free PDF
print driver. When printing your schematic, instead of selecting a
printer, select the PDF printer. I use PDFCreator, but there are many
out there that work well since they all use GhostScript. I like
PDFCreator since you can print to many different formats (PDF, PNG,
JPEG, TIFF, ...) and it can queue jobs so a couple different print
jobs can be combined into a single PDF file. It's free and uses
GhostScript.

 

[Joerg]

PNG is pretty widely accepted. Most modern image viewers handle PNG.
Web browsers handle PNG. Microsoft Word 2000 and OpenOffice handle
PNG.

That is great. The PNG files from Eagle look really nice when magnified.

Joerg, If you want to print your schematics to PDF, get a free PDF
print driver. When printing your schematic, instead of selecting a
printer, select the PDF printer. I use PDFCreator, but there are many
out there that work well since they all use GhostScript. I like
PDFCreator since you can print to many different formats (PDF, PNG,
JPEG, TIFF, ...) and it can queue jobs so a couple different print
jobs can be combined into a single PDF file. It's free and uses
GhostScript.

Good idea. Don't know if Eagle will like it though. I have that one bug
in Eagle that is really weird. On the first print attempt of the day
nothing happens. No error messages, nada. Then I have to select another
printer and click back to the one I want and from then on it works.
Every day.

 

[jasen]

Indeed. Tried it with the project I finished yesterday. It's sent to the
client already so too late this time but when I stored it in PNG the
schematic shrank from about 1MB for 84K. Is PNG widespread and commonly
readable? I can read it but that doesn't have to mean anyone can.

Anyone with firefox or internet explorer can...
and there's a bunch of other tools too, but unless done at a really high
resolution what looks good onscreen looks crap on paper, that's why vector
formats (ps,pdf,etc) are often preferred.

Bye.
Jasen

 

[Joerg]

Anyone with firefox or internet explorer can...
and there's a bunch of other tools too, but unless done at a really high
resolution what looks good onscreen looks crap on paper, that's why vector
formats (ps,pdf,etc) are often preferred.

Actually, small PNG of under 100K per schematic page print very nicely
out here. Even when printed in B-size or larger.

 

[joseph2k]

That's how I did that in the early 90's. OrCad SDT and Word for DOS. But
now? Eagle doesn't even have a native HPGL output format :-(

Maybe it's not needed much anymore. One of the main reasons were early
laser printers. My first one could not take more than 1MB in additional
memory and even that cost a bundle. Barely enough for a dense schematic.
But since it was an HP it understood HPGL perfectly well and printed
marvelous schematics from that. The newest printer here in the office
has oodles of memory. It can store a big fat stack of pages and print it
all out later.

Please remember, HPGL was originally about how to talk to pen plotters and
have text fonts, and filled shapes.

 

[joseph2k]

Anyone with firefox or internet explorer can...
and there's a bunch of other tools too, but unless done at a really high
resolution what looks good onscreen looks crap on paper, that's why vector
formats (ps,pdf,etc) are often preferred.

Bye.
Jasen

My memory of the development of postscript is that it is a page
description / layout language oriented around text with some pictures and a
few lines. It was the final pre-press output for the CSULB school
newspapers in the 1980's. PostScript was not created as a vector drawing
language the way i remember it.

Please see: www.adobe.com/products/postscript/pdfs/PLRM.pdf