Another IIci ROM hack

[trag]

Regarding the price calculations at seed studio, I think you overlooked the surcharge for going with thinner circuit board. Or am I misremembering that?

[dougg3]

The page says:

(The costs of 0.8mm, 1.0mm, 1.2mm, and 1.6mm are same)

Another awesome thing about that place

[Trash80toHP_Mini]

Are you talking like axial electrolytic capacitors, or something else? What kind of capacitor could I use? Either way, I like it! I didn't even consider just skipping surface mount capacitors. With the through hole sockets, it may be easier just to use through hole capacitors as well. Pretty cool I think this may work out OK actually.

Yup, axial caps. Check out the multiple contact shielded ribbon cables jumpes on the left!

If you need some for 2-sided proto-board for the project . . .
. . . I think I've got a box of 1,000!

edit: it's an almost entirely full 250 quantity box of AMP part # 88315-1

I got them for doing Mechanical Switch KBD PCBs, which are basically one sided boards with some patch wire "trace jumpers."

[dougg3]

Ah, thanks! I think if i can use through hole caps, I'll be in good shape. I don't think I'm in need of any proto board but thanks!

Well, I'm almost done routing the through hole PLCC socket SIMM. It's a bit taller now (about 1.5 inches). Any clearance problems in the SE/30 for instance?

Also there isn't a lot of room for much ground fill type stuff, especially near the sockets because I have so many traces going through them. Will that pose any problems?

[tt]

There is not too much clearance inside the SE/30 since the motherboard sits in the basement of the case, so there is a chassis directly above where the ROM and RAM stand. I am guessing by eye the clearance is about 0.25" when looking at the gap between the stock SIMM and the chassis.

Your surface mount board looks great. Is it the completed design? Looks like moving the caps to the back opened up the design a little bit. As far as assembling I would try a paste stencil and a hot air gun or hot air solder rework station.

[dougg3]

Do you know by any chance how tall the original SIMM is? Also, are there any clearance issues as far as how far things stick out from the SIMM? If we put through hole caps on it, that also becomes an issue.

Thanks! I think it is the completed design until I start making it USB programmable. Yeah, it definitely opened up space by putting the caps on the back. I'm designing a through hole version now. I'm thinking I might just order some surface mount boards now and then finish the through hole version after that. It's a learning experience for me! I like the solder paste/hot air idea too. I think I saw a YouTube video where someone put together a board with that combination and it looked really easy!

[tt]

The IIsi ROM measures 1.100" with my digital calipers.

[dougg3]

Excellent! That's the same height that my example SIMM is, and it's also the height of my surface mount PCB layout. I'm still messing around with the through hole one, but I'm not sure if I will be able to get it down to 1.1 inches. So we'll probably have to do the surface mount one for the SE/30.

[Trash80toHP_Mini]

Piccies?

[dougg3]

I don't have anything interesting to show pics of yet. The example SIMM I had was from a LaserWriter. I can take pics if I want, but it's probably not that helpful since it's the wrong pinout.

I have actually sent off my first batch of surface mount boards to Seeed Studio for manufacturing. I will put a design that olePigeon comes up with on the next round of boards. I figure that I'll find some major goofup with the first one anyway, so I didn't want to order a bunch of them yet. I'll keep everyone posted on the status of the order! Unfortunately I had to pick Registered Air Parcel so it'll probably take forever to get here...oh well.

We'll see how it goes, and I'll continue playing around with through hole mounting! I could post some pics of what I have so far for the through hole mounting, but it's not quite done yet.

[bigmessowires]

It was 17 calendar days from order to delivery, last time I got PCBs from Seeed. That was with the cheapest shipping option. I wrote a mini-review of their boards here: http://www.bigmessowires.com/2011/06/24 ... pu-boards/

[dougg3]

Oh nice! That's not bad at all, hopefully I'll see similar results. Thanks for linking to your review...interesting stuff!

[olePigeon]

Any suggestions for a logo before sending out board designs? Something piratey?

[Trash80toHP_Mini]

Keira Knightley?

[olePigeon]

Does the ROM SIMM draw power? Enough to light up 2 tiny LEDs? I could make the classic skull & crossbones, screened over two tiny red LEDs for the eyes.

[dougg3]

Hahaha, that would be awesome. I don't know how much current the SIMM socket can supply (a hardware guy can answer that) but it would definitely feasible to add from a layout standpoint. I think we'd need resistors in series with them to limit current, right? I'm too lazy to look at parts and do calculations on necessary resistance and current draw right now

That skull and crossbones sounds like a cool idea!

Or you could do a zombie Keira Knightley with red LED eyes! LOL, just kidding.

Order update: the PCBs I ordered are now "In Production" and I got an email saying if they meet requirements they will be shipped in 4-6 working days.

[trag]

Keira Knightley?

Preferably in that little top she wore to the nightclub in "Bend it Like Beckham"

It won't be very piratey. But rowrrrrr.

[Trash80toHP_Mini]

Maybe mix leather bra and war paint from KING ARTHUR with some Flintlock reloads (single shot "speedloaders") crossed pistols and some piratey short breeches!

[olePigeon]

So it's not Keira Knightley, but here's a modified Jolly Roger [EPS download here]:

[dougg3]

Niiiice! Now I just have to figure out how to add it to the PCB. Unfortunately it looks like FreePCB doesn't allow me to import graphics to put on the silkscreen, but there are tools out there that will "simulate" it with a bunch of tiny text areas. Hopefully it turns out OK!

[olePigeon]

You can do basic lines and shapes, right? Like putting boxes around certain areas, labeling them, etc.?

So here's a "trace" version of the Jolly Roger. [EPS version here.] I kinda like it better because it's very 80s retro.

[bigmessowires]

That's awesome!! I love the via in the skull!

[dougg3]

I agree, that's really freaking cool! I think your "trace" design will be a lot easier for me to replicate. I know that better PCB design software can probably just import the EPS directly. I'll try to trace it as well as I can with the line segment stuff.

The footprint editor will let me make stuff like that with lines and curves, so I'll see what I can do.

BTW, here's my latest find, from a seller on Amazon when I got lucky and found it for like $20:

It was originally a library book at USF (South Florida or San Francisco, I guess!) until last year. Not in the greatest condition but considering how hard it is to find the book, I'll gladly take it!

[olePigeon]

Can your program import EPS any other vector data?

[dougg3]

Unfortunately, it can't. That's what I get for using this stuff. I can draw my own footprints inside the app, though. I know that sounds ridiculous, but it's true. No import function for it