Building an Evolvable Motherboard PCB from foil pattern.

[diracshore]

Hi all,

I am trying to recreate a PCB from the paper below. I have attached images from the paper.

The foil pattern is described....

'Printed circuit board foil patterns are shown here for the 48x48 evolvable motherboard used
throughout this thesis. The printed circuit board is double sided, through-plated. If through-
plating facilities are unavailable pins can be soldered through to join the two sides. Note that these
patterns are not to scale.'

How best to go about producing this PCB ? Most of the firms I have contacted want gerber files, but this is all I have.

http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.109.5894

[IanB]

You will have to adjust them to the correct scale and print them out as an etch resist mask for making your own board. This is a standard procedure where you print the circuit out onto transparent or translucent film or paper and expose the pattern on a UV sensitized copper clad board ready for etching. If you are not familiar Mike has a good summary here:

http://www.electricstuff.co.uk/pcbs.html

Also the patterns you showed look like they have been through a fax machine. You should try to obtain much higher quality artwork if you can before creating an etch resist mask from it.

[IanJ]

Hi,

A few years ago I used to use a company called ZOT Engineering in the UK to make our companies PCBs. We did on occasion send them very old printed artwork which they were able to use.

You'll have to do a bit of repair work on some of those traces though.

Ian.

[diracshore]

The scale for the image has not been stated. I think if I know the measurement between the pins on the IC sockets I can extrapolate the correct scale.
Here is a datasheet on the IC,  Harris CD22M3494SQ

http://www.sussex.ac.uk/Users/adrianth/lazwebpag/web/DataSheets/FN2793.pdf

So what type of socket is that ?

As far as the artwork, is there an program to fatten and clean the traces or must I do that by hand ? Can it be done in photoshop / the gimp ?

Schematics for the board here for those that are interested,

http://www.sussex.ac.uk/Users/adrianth/lazwebpag/web/Motherboard/Schematics/Schematics.htm

[Alex]

Interesting concept. For the other curious here, this motherboard is a large analogue switch matrix for the development of analogue circuits. Kind of like an analogue FPGA. I would like to know what the research objective is if you are doing research on/using this array.

The older members here will have experience with copying artwork straight off magazine pages and making PCBs, maybe correcting a few traces with a marker. The younger ones are used to zip downloads of pdf files and the more adventurous to high quality magazine artwork and scanners. I dont think there is much overlap there, so a photoshop-type expert would be my bet.

Anyway, that is a standard PLCC44 socket.

[alm]

Another way would be to make sure the scale is correct and then trace the image in a PCB design package. Probably a fair amount of work, but it does give you proper gerber files that you can send to any PCB manufacturer.

[andersendr]

Eagle can import bmp images into any layer you want.  import-bmp.ulp Read up on that then you could just import them into the top and bottom layer of copper.

[hacklordsniper]

Eagle can import bmp images into any layer you want.  import-bmp.ulp Read up on that then you could just import them into the top and bottom layer of copper.

I tried that more than one time but it never worked as it should

[diracshore]

Eagle can import bmp images into any layer you want.  import-bmp.ulp Read up on that then you could just import them into the top and bottom layer of copper.

I will look in to that, Thanks. Is it possible I could import the schematic to eagle ? They are in postscript.

http://www.sussex.ac.uk/Users/adrianth/lazwebpag/web/Motherboard/Schematics/EMB1.ps
http://www.sussex.ac.uk/Users/adrianth/lazwebpag/web/Motherboard/Schematics/EMB2.ps

[diracshore]

So my plans for this project are to recreate the PCB from the schematic, replacing the ISA interface module with a USB connection. I may need some help. I will either use Orcad or Altium. I am going to release the gerber files when I am done as open hardware. Then after I understand the system better I will revise and update the board with faster and larger switches and rewrite the software with a GUI. This is one of the most innovative projects I have seen. It has been in the back of my mind for several years. I am curious to see where it leads.

How best to go about replacing the ISA interface module ? The schematic for that is on page 66 here

http://www.informatics.sussex.ac.uk/users/adrianth/lazwebpag/web/Publications/THESIS/ssxdphil.pdf

I was able to get a number of tutorial videos for Altium Designer. I have used CADs before. Still I am not sure where to begin. For the laying out of the bus lines what topics should I study ?

[free_electron]

Simple crosspoint switch but.... Long obsolete...

[diracshore]

What do you suggest as an update to the crosspoint switch ? What is the common standard and what is state of the art today ?

Speed is far more important than size in this application.

[Psi]

You might get a better image if you stick what you have through vector magic.

You can specify the number of colors and play around with the detail level until you get a good highres vector image which you can turn back to bmp/jpg.

[diracshore]

Thanks for the suggestion Psi. The vector magic site was too basic, results were useless, either shorts or just a mess. However I used an application, Inkscape, that cleaned the traces nicely. Took an afternoon of work but the results are amazing. I took the bitmap and converted it into a vector image, then back to a bitmap. Lots of trial and error in the settings but eventually I found the optimum.

The steps in Inkscape were,

1. import the image
2. path -> trace bitmap
3. Mode : Multiple scans (colors) / scans 50 / smooth enabled / stack scans enabled. Options : suppress speckles size (1) / smooth corners threshold (0.50) / optimize paths tolerance (0.10)
4. edit -> make a bitmap copy
5. edit -> copy
6. from another image editing program edit -> paste as new. I used the gimp.

The revised images are available here, too big to attach.

http://depositfiles.com/files/izzkclymg

[Psi]

yeah, i think the website only lets you play with the free version.

[diracshore]

The Evolved Radio and its Implications for Modelling the Evolution of Novel Sensors

http://www.duke.edu/web/isis/gessler/topics/evolved-radio.pdf

This board can do some bizarre things.

[Thor-Arne]

The revised images are available here, too big to attach.

http://depositfiles.com/files/izzkclymg

"This file does not exist, the access to the following file is limited or it has been removed due to infringement of copyright."

Anyway, I think retrace the board in a PCB design package would be the best idea if you need several boards. This will allow you to do some design rule checking also.

[poptones]

It appears to just be a big crosspoint switch. For your iinerest in this sort of thing You might be better served by checking out the psoc line, maybe getting an evkit. It has an 8051 or arm micro, programmable hardware, and configurable analog cells you can program like gate arrays.



Just found it: appears a psoc5 kit can be had for a hundred bucks. Yowza. http://www.cypress.com/?id=2218

[polysome]

The evolvable motherboard will soon be available in Gerber format under a open hardware license.

https://github.com/polysome/evolvable_motherboard

[scientist]

Eagle can import bmp images into any layer you want.  import-bmp.ulp Read up on that then you could just import them into the top and bottom layer of copper.

KiCAD can do the exact same thing, and the quality (resolution, dot size) is adjustable to your heart's content.