Peter's z80.eu site blog
Search 

Please read ! 
If NO IMAGES will be shown, use www.z80.eu/blog instead of blog.z80.eu

Please note also - THIS BLOG ENDS HERE WITH THE LAST ENTRY FROM NOVEMBER 9th 2021.

I have prepared a new blog with wordpress at https://vintagecomputing.info !!!

Thank you.
Predecessors of 8080 hardware.... almost forgotten - R2E Micral , a Intel 8008 based "PC" 
Thursday, February 19, 2009, 10:00 PM
Posted by Administrator
For many of us, they are not known or at least forgotten.... but 3 years before the Altair 8800, in January 1973, there was already a hardware available for computer enthusiasts:

The R2E Micral was one of the first, may be the first computer which can be called "Microcomputer", because it wasn't a cabinet sized hardware, it was in a similar size like an Altair, or even the first IBM PC.
Although it was based on an Intel 8008 Chip (running at a 500 Khz frequency), it provides additional instructions for interrupt handling and data manipulation. It was created from the "French National Institute for Agronomic Research" (I.N.R.A.) because of the lack of money for PDP-8 hardware.
It has a bus system similar to the S100 bus, called 'Pluribus', several I/O and memory cards were build. At least, 2KByte RAM was the standard design, but 16KByte could be used (14 bit address bus, 8 bit data bus) in total.
One year later a Two-Pass-Assembler was available, and also a high level control language.

For more information, please look at the following URLs:

http://www.old-computers.com/MUSEUM/computer.asp?c=352
http://www.feb-patrimoine.com/projet/micral/micral.htm
http://febcm.club.fr/systemes_ord/Micral_n.htm
http://en.wikipedia.org/wiki/Micral
http://www.nationmaster.com/encyclopedia/Micral
http://www.heise.de/newsticker/Vor-30-J ... dung/33686
http://www.avandor.net/micral.htm

A very interesting interview with the creator of that piece of computer history can be found at Wired.com: http://www.wired.com/science/discoverie ... 97/09/6850

To get an impression how it looked:

Also interesting... some Infos about a self-made (no kit, just plans and pcbs) computer in mid of 1973 - the Mark 8, also based on the 8008:
http://web.archive.org/web/200402160215 ... ark8b.html
http://www.bytecollector.com/mark_8.htm

1 comment ( 274 views )   |  permalink   |  related link   |   ( 3 / 2552 )
Cool ... an Apple II, a SD/MMC card for storage, a Z80 CPU, 80 columns card, all together implemented in an FPGA prototype 
Friday, January 30, 2009, 08:00 PM
Posted by Administrator
Amazing what is possible !
An Apple II and some peripheral stuff, fully equipped, and almost 100% compatible, but not running on old hardware - it can be done with a prototype board (Altera/Terrasic DE1 board).

Alex Freed did that ... his first steps began earlier with his FPGApple, Pseudodisk and other fine ideas, now he began to create an improved version.
See http://mirrow.com/FPGApple/revisited.html for more details.

Wonderful ! If he finishes his implementation of the Z80 part also (to use it with CP/M), for sure I am really interested.

Inspiration comes also from this site:
http://www1.cs.columbia.edu/~sedwards/apple2fpga/ so be curious and take a look also there.

The development board costs about $ 150, this is not too much if all planned functionality can be used.

URL has changed meanwhile, see link at the bottom.
Also, there is another site already offering a full blown Apple IIe in FPGA: http://www.applelogic.org/TheAppleIIE.html
add comment ( 255 views )   |  permalink   |  related link   |   ( 3.1 / 2549 )
I managed it to downgrade a Turbo PASCAL (5.5) Source of a Z80 Assembler to a Turbo PASCAL 3.0 version...  
Saturday, January 24, 2009, 11:00 PM
Posted by Administrator
... and it can be compiled on DOS error free. Now I tried it on CP/M 3.0 and guess what happens ?

It was too big, over 50KB size was too much for the Compiler. So I was reminded on these days and the size limitations suddenly again :-(

I am sure it can be stripped from all comments, and also from unnecessary blanks inside the source file, and then it will work even with CP/M again.

Now somebody can ask for the reason I tried this. There are many Z80 Assembler available, and many are very useful and runs smooth.
But there are no source code version of these Assembler available, and even if so, they are written in assembler also, a few in C. But so far I didn't found any source code for Turbo Pascal 3.0, and so it was very exiting for me to get one.

I will try to publish a ready compiled version as soon as I get time to strip that source code down, under DOS (with TP 3.0) it runs already smooth.

Update: You can download the whole package from http://www.z80.eu/downloads/asmz80.zip

4 comments ( 286 views )   |  permalink   |  related link   |   ( 3 / 2483 )
Another very interesting vintage computer blog ... not very frequently updated, but good entries ! 
Tuesday, November 25, 2008, 11:00 PM
Posted by Administrator
I found surprisingly two other vintage computer blogs,
one from Howard Harte at http://hartetechnologies.com/Happenings/nfblog/
(with less entries for the present but many for 2007),
and a bigger one at http://www.bytecellar.com/,
with a bigger number of Apple II related entries.

Howard Harte describes the root (history) of CP/M and that was really interesting:
http://hartetechnologies.com/Happenings/nfblog/?p=18
You can also found some very interesting software pieces at
http://www.unix4fun.org/z80pack/
just look for "Bootable disk images with older Digital Research CP/M versions"
on that mentioned page from Udo Munk.

add comment ( 229 views )   |  permalink   |  related link   |   ( 3 / 1129 )
Cracking an Osborne 1 into parts - interesting pictures 
Sunday, November 9, 2008, 03:22 PM
Posted by Administrator
Very interesting pictures can be found at TechRepublic - they split an Osborne 1 part by part, hopefully they assembled it back to a working unit...

http://techrepublic.com.com/2346-13636_11-193055.html

As far as I know, that's an older one, not the newer model with less rounded case corners.
The detailed pictures from the Double Density are also amazing, because later computer models didn't need such extra logic due to more intelligent microcontroller like the upd765.

add comment ( 219 views )   |  permalink   |  related link   |   ( 3 / 3041 )

<<First <Back | 32 | 33 | 34 | 35 | 36 | 37 | 38 | 39 | 40 | 41 | Next> Last>>