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Interesting. Pretty quirky stuff. Not my cup o' tea.

I'm pretty happy to be moving forward with computing, rather than back. I'm sure that would be a good learning experience though.

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LOL at this part:

I decided to build a homebrew CPU computer of my own. My goals were:

    * Build the CPU from scratch, primarily using basic 7400-series logic. No 6502, Z-80, etc.

    * Keep the hardware complexity to a minimum.


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Interesting to see that he managed to get a MultibusTM wire wrap protocard. They cost a fortune back in the day.

I wired a couple as big as this, one of which was for IRCAM. It was a DEC LSI 11 format card, with some, (at the time) awesome High speed signal processor, including some TRW hardware multiplier chips that cost about as much as a whole, (cheap), PC does now. About as powerful as a DsPIC. I think I got into the same groove my mum does when she does embroidery, (She did City and Guilds needlecraft when she retired from teaching - her embroidery work is seriously good). You just sit there with your wire wrap tool and your netlist and get on with it. I used to do a set number of wire per night, the next night I'd test the previous nights run, by beeping it through with a continuity tester, then do another batch. I only ever had one not run first time, and that was because the designer had done a patch and not told me. If you are methodical, it's not hard, though it's a bit scary the first time you power the thing up....

It's cool to see a board like this now, for me, because it shows one of my favourite digital prototyping tools is not dead yet! I guess the flip side if this approach is making the whole thing on one big chip using FPGA. There are some cool ideas for this type of thing on ZXGate

I've just noticed they've done Jupiter Ace on one chip - I'm up for that, I was going to build a replica anyway, as that was the first processor I ever hitched to a synth, as a test for controlling a synth with an Apple ][ using FORTH. I couldn't keep th Ace and always fancied one. If you want a fast interpreted language, with a small software 'footprint', then forth is an interesting way to go. People like TK can usually do as well with a good macro assembler, but FORTH is quick to prototype in. The AMPLE language that controls the BBC Music 500 was a FORTH derivative. Most Music done in it was a bit cheesy, but a hint of it's power can be heard here: Music 500 Syncron Sound. More details are here: http://www.colinfraser.com/m5000/m5000.htm. The whole site is worth a look - this is the guy who designed P3 and a host of other goodies.

Meandered enough for now. Thanks for posting this link - anyone who builds a FORTH computer get extra points from me!

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ontopic... it's mad how many languages and uses for them are out there, and sometimes seemingly forgotten...

Ontopic.... I once made a list of the ones I'd actually done something useful in. It was scary. More scary was how many I can't even remember any more. I used to write in APL, but now I can't even remember what those funny squiggles mean. Chill anyone? I can still understand the EMS language, and I came to that by accident trying to decode an old performance written in it - it survives as Mouse . The link also throws up some interesting EMS stuff.

Other ones I've used once or twice include Fortran, COMAL, BCPL, FORTH, microProlog, CORAL 66, (OK I amit once - and never again). Still keep meaning to learn LISP.

Have you ever seen that file about shooting yourself in the foot in different programmiing languages?

My favourite was:

IBM 370 JCL: You send your foot down to MIS and include a 400-page document explaining exactly how you want it to be shot. Three years later, your foot comes back deep-fried.

(Warning to most MIDIboxers: this joke may be too old school for anyone other than us ancient geeks)

Next time I'm in the UK I challenge your Mum to a cross-stitch-off! She's goin' DOWN!!

OK, but you better see what you're up against: and this is a bad picture of one of her minor pieces....



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Thanks - you have in fact found a later, better, updated copy, Perhaps it should have an SVN.....

Yes, that's one of mum's hand made originals, Her own design and stitchery. She's basically a textile artist, though at coming up on 80 she's slowing the pace down a bit. She still doesn't wear glasses.

I got her a small kit from Leah Buechley' site, but she hasn't done it yet.


Coming back towards topic a bit,

A thought, you could make the first wearable MIDIbox appliance.

Thnking along random arty lines, I seem to remember that you have done some graffitti artwork, have you do any 'throwies' yet? Leah did a wall mural with conuctive paint and LED's it's  on her Flickr pages here, now a MIDI driven music interactive wall mural - that might look kinda cool.

A made a bunch of Throwies for some friend's kids. I used high intensity LED's, a flasher designed to max out the battery life, and ex hard disc magnets. For months I could see one flashing gamely away from a railway bridge in Machester,

edited for typos

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I've always admired the soldering info on that page ;)

[x] if your solder is not melting, make sure the wattage of your soldering iron is high enough. you'll need a soldering iron that's 30 Watts or greater.

[x] if your soldering iron tip is sticking to the bead, make sure your soldering iron tip is clean. the tip should be brand new. be careful not to get any solder on it - this will cause the tip to stick to the bead. use steel wool and fine grit sand paper to clean your tip.

[x] if your soldering iron tip is sticking in the bead, make sure your soldering iron tip is the right shape. I used a RadioShack brand 30 watt soldering iron with a standard RadioShack tip. nicer irons with delicate tips won't work well. you want a relatively blunt tip that won't get stuck inside your beads.

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Back to topic, a full MB system is maybe not a BMOW but still a Middle Mess of Wires. When everything is connnected, are not there too many entangled ribbon cables ? I would not want to build one set of core and modules with their current layout. Remember, most failures come from bad connectors. Depending on project's case, why not draw all boards with a common power & I/O channels layout, to allow 2D flat chaining, 3D vertical stacking like PC/104 systems, or even keep all the boards panelized in a single large one ? There is fee PCB software that is enough for two-layer boards and without the limitations of Eagle.

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I have been drawing you designs for a 32 pin backplane that uses DIN 41612 connectors, (with any arrangement of pins, because they are all in parallel), to carry power, I2C, CAN, Audio etc for a rackmount verion of a 6 SID MIDIbox, using a eurocard sized perfboard for a core and 2 SIDs. By running the other I/O along the 'plane', I will then be able to plug in CV and filter boards. This will certainly come into the 'messy' area. The advantage of borrowing old style computer and industrial control style here is that I can start with one board and add on. The reason for 6 SID's is that I want to have a remote control  surface using CAN, and that wiill 'eat' the other core, but not have any SID's. Using the proper CAN interface chips at each end of the remote cable should ensure reliability, and I will probably run 24 or 48 volt power to a little switchmode module in the remote to keep the power current in the cable down, as is done with Power Over Ethernet (POE), devices.

Looking at the original BMOW, one thing to remember is that many Supercomputers and 'Big Iron' mainframes used wire-wrap for all their backplane connections and custom boards, and they were very reliable. It was regarded as just as reliable as solder, and in certain cases, more so. People who talk about proper wire-wrap corroding are usually mixing it up with one of the IDC prototyping wire-wrap systems, real wire-wrap connections form small cold welds at each pin corner of the wrap. that's metal to metal, 20 + times.

It does look messy, but it's clean and relatively easy to do. I only wish I could find some of the 'kapton' insulated wire that went with the Cut, Strip and wrap bit I have for my powered wrap gun. I could work much faster that way.

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