Pete C. wrote:

cavelamb himself wrote:

Pete C. wrote:


cavelamb himself wrote:


Don Foreman wrote:



On Tue, 07 Oct 2008 22:32:21 -0500, cavelamb himself
wrote:




What a mixed up strange world.

The local PCB shops won't touch a simple job for less than $2000 NRE +
board costs, but several shops in China can knock out a panel for $99 -
almost flat rate.

But (of course) they need a particular file format - which I don't have.

Not surprising, I guess. The last circuit board I had made was 20+
years ago - done with tape and stickies on film and photo reduced.

I've been all over the net tonight looking for a DFX to Gerber
translator - which are avialable - Free Download!, but cost big bucks
to license. (trial copies work - but leave out some items)

Is there anyone in the house translate a few dxf files to gerber?

Or?
Know of a PCB prototyping house that's affordable and can translate?

A single double-sided board - 5-12" x 6" - with silkscreen - less than
1000 holes.

It's not a commercial product - just something I wanted to play with.


Ping these guys:
http://www.4pcb.com/

Pinged! Or is it Punged?

That's a pretty good offer - about the same as China.
But I'd like to have 4 OZ copper.
Will talk to them tomorrow.

I really like the special student offer!

Free MacDonald's gift card with every order of less than 4 and special
pricing too!

This looks like more complete software than Eagle.
http://www.4pcb.com/index.php?load=content&page_id=46

Anybody want to make odds on whether an autorouter can complete my
little board in the same space?

I'm offering 10:1 against.

--

Richard

(remove the X to email)


Dude, that looks like a really old design, can you even source some of
those parts? I think a redesign with more modern parts would cut the
parts count, board complexity and physical size considerably.

You obviously know your stuff, Pete.

It is indeed an old design.
An 8088 cpu running at either 5 or 8 Mhz.
Basically the central core of a Turbo XT clone.

Yes, all the parts are still available - and cheap!

The only "new" parts on the board are the memory and Max232 level shifter.

(I have an 8256 in my parts box - which would really reduce parts count,
but I'm not convinved that one is still easily available)

The memory parts are 512k x 8 static ram (and EPROM) in 32 pin DIPS
(awesome stuff!)

I have software for Z80 and 8088 BIOS / monitor.
After a lot of head scratching I picked the 8088 over the Z80 because
it's code compatable with my host computer. And I like MASM.

And there is less brain dammage potential sticking to a single assembler.

As for board size and complexity, it's a 512K XT (minus video and
keyboard) with timer, interupt controller, serial port, switch port,
4 blinky LEDs, and a virgin 8255 for user IO.

And a good bit of MSDOS compatable interupt functions.

If you can't blink an LED with all that it's time to take up knitting!

--

Richard

(remove the X to email)


Might want to pickup that copy of Circuit Cellar and review all the PC
type SBCs that are available for a couple hundred dollars complete
before you reinvent the wheel.

I've read Circuit Cellar since it was an article in Byte magazine.
But they have pretty much gone the way of the OPic.

My intent here IS to reinvent the wheel.
Or ACTUALLY, to simplify a wheel.


--

Richard

(remove the X to email)