Peter's z80.eu site blog
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, 07:00 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 ( 146 views )   |  permalink   |  related link   |   ( 3.2 / 2001 )
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, 10:00 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 ( 173 views )   |  permalink   |  related link   |   ( 3 / 57 )
Two interesting pages about the Olivetti M20 - one of the few computer which have a Z8000 and can run CP/M-8000 
Monday, December 15, 2008, 10:25 PM
Posted by Administrator
Full with additional links and infos, more than just a vintage computer museum entry:

http://retrocomputing.altervista.org/m20/m20.html
http://www.retrocomputing.serrantoni.co ... tim20.html

To get an impression from what I'm talking - here's an image from an M20 machine,
running CP/M-8000 (click on the picture to zoom):


The machine was selled in 1982 with PCOS (that's an operating system with cryptic commands, even more cryptic than CP/M was)...

There was an additonal 8086 card available to run MS-DOS, but that's another story.
The cpu was - to document it more accurately - a Zilog 8001, the cpu family is named 'Z8000'.

Still one of the most "rich" web pages about the Olivetti M20 can be found at
http://www.z80ne.com/m20/

2 comments ( 170 views )   |  permalink   |  related link   |   ( 3.1 / 5902 )
Another very interesting vintage computer blog ... not very frequently updated, but good entries ! 
Tuesday, November 25, 2008, 10:00 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 ( 135 views )   |  permalink   |  related link   |   ( 3.3 / 258 )
Cracking an Osborne 1 into parts - interesting pictures 
Sunday, November 9, 2008, 02:22 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 ( 130 views )   |  permalink   |  related link   |   ( 3.2 / 3224 )

<<First <Back | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | Next> Last>>