View Full Version : Looking for a dump/source of MicroWorld BASIC Interpreter for the 2650

March 18th, 2014, 07:57 AM
Hi guys,

as the title says : "Looking for a dump/source of MicroWorld BASIC Interpreter for the 2650".

Long time ago I made this system, I think I talked about it somewhere else can't find the reference :

Picture of the semi-finished board. (http://www.gilesgoat.com/Yak/SigneticsBoard.jpg)

It contains a "bootloader" that allows to peek/poke/dump memory, a 6850 UART, 32K ram and an IDE interface I yet have to test.

It also has an XMODEM loader that allows you to load in some SW and run it.

I've seen the manual of this MicroWorld BASIC and seems quite cool but that's all about it, can't find a rom/dump/etc. anywhere.

I also happens I tried to make a certain dump of a certain FORTH I found can't remember where "almost working" but it had some strange problems, was crashing when trying to use stuff like : ..

Any pointers in any direction appreciated, would be nice to have that basic running again.

When I finished to write it, if anyone is interested, I can put a PDF here describing the board.

March 18th, 2014, 05:44 PM
Very interesting project. I'd be very interested to learn more about it.


March 19th, 2014, 02:53 AM
Probably no connection at all, but a long time ago (late 70s early 80s) an australian company called Applied Technology released their own version of a BASIC interpreter called MicroWorld BASIC. I still have the manual for it. This was for their Z80 S-100 bus machine (which I built at the time) however the company had earlier released a 2650 CPU S-100 board. I have an unpopulated PCB for this, fished from a scrap bin because a lot of the traces weren't etched properly. I wonder if they'd done a 2650 BASIC for that board?

Update: Apparently they did have a 2650 BASIC, found some more info here: http://www.microbee-mspp.org.au/forum/viewtopic.php?f=31&t=317


March 19th, 2014, 04:21 AM
When I finished to write it, if anyone is interested, I can put a PDF here describing the board.

I'd certainly be interested. I've a pair of 2650 CPUs that I'd like to use for something :)

March 19th, 2014, 06:44 AM
Did you try this site: http://www.tubedata.info/phunsy/index.html

The interpreter is not posted, but maybe he has it.


March 19th, 2014, 08:18 AM
Ok I got in fact something, someone gave me a dump of that BASIC he made and maybe I should be able to make it work :)

Ok also "as soon as I'll be able to sort out the docs" ( and check it's all correct ) I will post a link/upload here a PDF ( made using the glorious LaTEX ) which describes in full the system "enough one should get inspiration and/or make a copy of it".

It's nothing "mega/special" but fundamentally is CPU + RAM + ROM + CPLD for logic + UART + a modified version of Phil's P.R.I.D.E interface.

Now little problem I can think of, I did use an XC9536 CPLD ( 5V ) I don't think they exists around any more, you could replace it with an XL9536/72 I think but you'd have to add a 3v3 volt regulator somewhere ( they still are TTL tollerant ).

One thing I could NOT work out was "if the 6850 ( UART ) needs CONSTANTLY the presence of E1 clock to work " ( I suppose so otherwise how could it serialize/deserialize stuff ? ) so with " a lucky trick " I managed to have it synchronized with the CPU clock, alas the 6850 goes 1 Mhz only when the CPU could go 1.25 Mhz but in this way they all go 1 Mhz.

It fits all in a standard 160x100 eurocard 3U.

Give me just a bit of time to sort out things and I'll post all here.

March 22nd, 2014, 07:35 AM
Ok just to let you know "the PDF is done" but I wish one person first to have a look at and give me an opinion before I post the link here :)

I hope it will be inspirational for other people here having that CPU and maybe willing to build something simple around it.

With that PDF and a bit of work and time you should be able to replicate ( modify, improve ) my small SBC and have fun with it :)