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Just finished an "old school" computer kit.

O

Oldbitcollector

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Jun 7, 2012
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While this isn't vintage, it was designed to have the vintage feel of the Commodore and Atari systems of the 80's. I just completed this "old school" computer/electronics kit. (Designed the board, and configured the BASIC to emulate some of the functions of graphics and audio chips of the old 80's machines).

It's designed off a Parallax Propeller Microcontroller with 32K, so after you load the BASIC interpreter you have around 4k of tokenized BASIC left. The BASIC is relatively full featured, and the project itself can load other programs.

Thought you guys might find it interesting.

Here's the Instructable:

http://www.instructables.com/id/Build-your-own-pocket-mini-computer/

OBC
 
If 80's machines are your pleasure, you might want to look into the PIC32 MCUs. MIPS R4000 architecture, running at 80MHz with 32-bit words. Even available in 28 pin DIP for the through-hole clan.
 
Just thought I'd poke in an update on this project tonight..

Toward the end of July, we ran into supply/demand issues with our supplier and moved the entire project to it's own website/forum/and formed a company to fill orders (along with other related projects).

I just released version 2.2k (Now the 11th firmware revision since we went live with the project) adding features to expand capabilities and fix bugs.

It also has it's own website (propellerpowered.com) and most importantly it's own support forums at:
http://propellerpowered.com/forum/index.php?board=5.0

Outside of running BASIC, it has several other interesting binaries including few decent games, a port of the Zmachine emulator, and a very "Commodorish" looking SIDplayer.

I figure there's about thirty to fifty of these out in the wild now, so it's starting to become interesting.

If are you looking for a fun DIY computer project to play with that isn't overwhelming I invite you to give it a look.
While there is a KIT, all of the schematics and code are open licensed and we welcome everyone to join in.

Edit: Forgot to add the new Wiki site that has details about the project:
http://propellerpowered.wikispaces.com/

Jeff
 
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From website:
I wanted to create a product which would give those in the younger generation a chance to see what computing was like in the early days before the PC.
Click to expand...
Back then, it actually was all about the creaking, clanks, and four-letter words.

Chuck(G) said
PIC32 MCU
Click to expand...
I keep waiting for someone to use these, or a competing RISC-core uC, to put 16~32 on a board, as a workstation, reconfiguring each uC's role on the fly, dropping them into standby based on demand, etc. Instead, we're still all wedded to Intel's "one big chip" philosophy.
patscc
 
patscc said:
I keep waiting for someone to use these, or a competing RISC-core uC, to put 16~32 on a board, as a workstation, reconfiguring each uC's role on the fly, dropping them into standby based on demand, etc. Instead, we're still all wedded to Intel's "one big chip" philosophy.
Click to expand...

There are certainly multicore ARMs. Putting several of them on a single board isn't that hard.
 
Actually, being a "Propellerhead", there's a pretty easy way to expand this project into two Propellers CPUs (one exclusively handling video, audio, kinda like a SID/VIC chip), but it would raise the cost of the project sharply, so it's not in the immediate plan.

Besides, there is a still a lot of ground that I haven't managed to cover with this project. (and a lot of letters left in the alphabet for revisions :) )

Jeff
 
Since the Propeller is based on the CDC 6000-series model (PPUs in a barrel and the CPU as the hub), what I found disappointing was the rather weak "hub". The Propeller 2 looks to be more on track, but I take it that it doesn't exist yet.

Some of the Freescale Coldfire MCUs have dedicated peripheral processors in something of the same model.
 
patscc said:
Speaking of, and this is slightly off topic, but how the heck did they rebrand as freescale, anyway ?
patscc
Click to expand...

Oh, it;s a sordid tale. Back in 2003, Motorola figured that the IC business (and particularly the MCU business) should be spun off, so there was an IPO and things look good. Enter the Blackstone Group, the Carlyle Group and others who orchestrated an LBO of Freescale that left it with over $6 Billion in debt. That debt still hangs around the neck of Freescale, hobbling it severely. Had the corporate raiders not gotten to it, it would be a far different company today.

Modern American Capitalism at its finest. :rolleyes:
 
I've built this, although via a slightly different route.. Jeff's PMC kit consists of a Propeller Quickstart board plus a second board which provides audio, VGA, PS/2 kbd, and microSD sockets and optional extra memory. And more I/O, I forgot some of it I'm sure. That board kit is called VGAplus and can be ordered separately, which is what I did because I have a couple of Quickstart boards already. I added that extra memory but left out the microSD for now.

Interacting with the PMC does resemble the computing of old, just with a VGA display. What's nice is that this is a pretty generic system, both software- and hardwarewise. I plan to try to run Forth on it, for example. And the two boards pop easily off each other (that's how I store them actually) you can use just the QS board with a laptop computer, or something (I just found that my Asus android tablet seems to recognize its FTDI chip when I connect it through USB so I may research that route one day. And other people are already using a Raspberry PI instead of a PC). And program its 8 LEDs or 8 touchpads. When I go on vacation in a while I'll bring the PMC and a very short USB cable - the two boards are area-wise smaller than credit cards and fits in a tiny box.

I run a Z80 emulation plus CP/M on another small Propeller board and I would be surprised if it wouldn't be possible to fiddle with that to get it running on this PMC too. Or at least with the 8080 emulation which is smaller.

All in all versatile and low cost fun.

-Tor
 
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@Tor

I just started fiddling with ZiCog (CP/M) emulation, is there enough resources here to get it to run on this configuration?
I'd love to see more than just BASIC work with this.


Jeff
 
@Jeff,

So far it's only been a thought, but I intend to explore it. Without looking closely I would guess the main issue is how RAM can be handled, and if we've got enough of it (but CP/M can still work with less RAM). ZiCog needs only a single cog of course so that won't be a problem. What I don't know (and where you're in a much better position) is if it's possible to use the SRAM on the VGAPlus board as extended RAM the way it's done in e.g. the RamBlade or DracBlade, where it's 'paged' in somehow at need (I've never looked deeply into that). (And for amount of RAM there's that new 128KB chip you're testing..)
But I would be very surprised if it's not possible at all.

Unfortunately I've just started a period at work with double assignments, so all my spare time is gone for a while. I'll bring my VGAPlus and a QS with me on a two-week vacation in a couple of months and start playing :)

-Tor
 
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