I'm closer to the opposite extreme than Bob. It's useful to model the
individual gates so the schematics somewhat reflect the intended design. For
example, each transistor in a dual MOSFET is drawn as a transistor, not
abstract pin numbers in box. I'm often unaware of actual pin numbers and
function even during board layout.
Full agreement here that Eagle's interface is quite different from any other
application. The "alien" nature is very likely due to its origins in East
Germany (I think.)
I also echo Bob's sentiment to learn the library functions quickly. As often
as not, each new board adds a few new chips or packages to the library. PICs
are a special case. It's pretty straightforward to draw the new chip, more
so than stretching an existing one and renumbering pins. I sometimes think I
want to add symbols inside the block to indicate pin function -- e.g.:
comparator or A/D -- but never actually get around to doing so. Even if I
did, the configuration will be different on the next board even if it was
the same chip. (It sure would be nice to modify one of the those graphical
PIC configurator programs to spit out a custom Eagle symbol along with
configuration code. I don't expect I'll ever get around to that either.)
----- Original Message -----
From: "soffee83" <soffee83@...>
To: <Homebrew_PCBs@yahoogroups.com>
Sent: Monday, January 16, 2006 2:07 PM
Subject: [Homebrew_PCBs] Re: Help with a PCB layout
> --- In Homebrew_PCBs@yahoogroups.com, "Bob Hyland, PMP" <BobHyland@A.
> ..> wrote:
>>Does anyone know of a library for Eagle that includes the PIC16F7∗7
>>devices?
>
> Hey Bob,
>
> Lately, I've just gotten in the habit of grabbing the generic DIL
> packages from the "ic-package" library in whatever pin config. that I
> need and making my own connections to that. I'll also use pin headers,
> sockets, or anything else that has the right footprint and pin
> spacing. You can also tie pins to ground planes or supply lines, or
> copy/rename library items and customize them graphically or designate
> the pins. Be warned- The create new item features in Eagle are useful
> and necessary, but extremely WEIRD and maybe not so intuitive (as are
> some of the group and copy functions). It's a wonderful program, but
> it may have been written by aliens (I know the manual was).
>
> I also haven't been using the schematic much lately, but it would be
> useful as a circuit reference for anything complicated. I've been
> adding all my chips in the board app, then connecting all the wires,
> then dragging them all over the blank area around the board and
> rearranging or rotating them until I have the least amount of criss-
> crossed lines. Then I move them into the board area and start trying
> to route. You usually still have to move some after that. You can also
> easily rotate with the right mouse button, while you're using the move
> tool. Unless I'm doing something wrong, moving them after you've got
> route lines happening can get really messy. It will keep the original
> lines and turns, and let them cross over themselves, add segments to
> them,etc. I usually rip up the routes beforehand for anything that
> needs moving.
>
> Good Luck,
> George
>
> PS- There's a user library folder somewhere in the ftp at Cadsoft
> (maybe in user or pub). Could have your PIC, or another one with the
> same pinnings (Microchip usually has a few similar ones).
>
>
>
>
>
>
>
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