root@sbcs.sunysb.edu (SBCS Systems Staff) (04/21/88)
(repost from comp.lsi.cad - dunno if anyone supports that group)
What PCB layout packages are you using, if any? We've a copy of PCAD 2.X
and generally aren't impressed with the package. The problems with
PCAD are:
o No real support for busses, in the electrical sense.
o Macro support is not really strong at all, eg it is fairly
hard to define a "one mByte memory cell" composed of say
8 1Mx1's and then plunk it down freely. I think we would
like something on the order of SCALD's macro capability.
o Fairly hard to define library parts. For example, the
standard package doesn't give you generic footprints,
and when entering a part, you have to enter the pins/pin nums
twice (once defining the schematic symbol, once defining
the PCB footprint). Entering the 68030 was a real pain :-).
Some third parties supply automatic library generators,
but they are extra bucks.
o Generally, libraries are slow in coming and fairly expensive
when you get them from PCAD. Some elements of library style
are annoying under PCAD, eg an F374 is defined as a single
flop - when you want to use the part in perhaps the most common
way, ie a bytewide register, you gotta stack the 8 flops using
a macro. This is done for gate swapping purposes, but just ends
up a being a stupid waste of time. Word from big system cad
houses is that gate swapping isn't really necessary most of the
time anyways.
o Autorouter is slow and generally doesn't achieve high completion
percentages. An 80386 box helps the "slow" part.
o Software requires use of cumbersome dongles, one for the
autorouter, one for schem capture, pcb layout, etc. With the
large bucks they charge, you would think they would at least
ship a dongle board, or just admit that they will lose a few
copies to pirates. This is just an opinion on a more global
religious war, so pls, no mail/postings on this point.
o Even discounted, we've spent around > ~$5500 to date.
o Until recently, it was fairly tough to build a makefile for
running a design through the various filters. The problem is
that they like to print huge copyright messages everytime any
filter starts up. Also, current command line arguments are weak.
On the plus side, we tolerate PCAD because:
o Deep discounts for Universities - 75% off list price.
o They allow use of discounted software for BOTH research and
education. Some outfits, eg Cadnetix (I think) require that
you use their discount software ONLY for education - research
users get just 20% off list. Imagine having to play advertising
agency and then not getting paid.
o The schematics editor has a fairly nice user interface. Not
great, just nice.
o They are nice folks to deal with in general. Like almost
any other software comany in existence, they want money to
talk to you, but even without a maintenance contract I've
managed to get them to help fix problems.
What I would like to see in a package are:
o Good support for digital/uP design, eg busses, strong macro
support, good bus editing, etc.
o Higher completion autorouter, eg one with rip up, heuristics,
knowledge of busses, memory layout, etc.
o Not a lot of money, must be < $10K since we already spent on
PCAD. No restrictions on usage, eg research/educational.
o Lotsa up to date library parts. I need AS/ALS/F/ECL libraries
and recent uP's (ie keep your 6800 thanks!). Easy library
generation - just type in pins, and package and generator
spits out schematic + footprint. The schematic symbol would
probably require editing, but that is OK.
o Some connection with a foundry. Would like to just send a
diskette to a PCB house and get back a board. Noticed Analogic
has such a service advertised in MicroCornucopia that builds
double sided boards from diskette input for $1/in^2. Of course,
I need at least 4 layer boards, but...
o Would be nice if the package supported EDIF or at the very
least an ASCII custom format. I would like to be able to build
utilities to patch rough areas in the commercial package.
I would really appreciate any ideas that you have on what package to
buy next time 'round.
Thanks for your time!
Rick Spanbauer
SUNY/Stony Brook