Nicolas Welte's Hardware Projects
Welcome to my hardware projects page. I hope you will find something
useful here, I'm sure you will like the stuff if you're into Commodore
computers.
Looking for recent updates? Then have a look at the history and news page!
Projects
Universal 6502 RAM and ROM expansion
Upgrades/replaces RAM and ROM with a
32kB SRAM and 128kB FlashROM chip. By the use of a personality chip the
same hardware can work in a lot of different 6502 based computers and
peripherals. So far I made personality chips for the Commodore CBM and
PET computers, the Commodore VIC-20 computer, and the Commodore
1541/1571 disk drives and compatibles.
main page:
general information, parts list, downloads
construction page:
instructions for assembling the device.
configuration
guide: all DIP switch settings are explained here
disk drive flash
software: driver software for the 6502 expansion when used in
Commodore disk drives.
1541-II notes:
in this drive there isn't enough space for the standard board. Look
here how you can make it fit.
prototype
pictures page: shows early versions and applications examples.
Universal Flash/EPROM adaptor
A small adaptor board that allows you
to use large Flash-ROMs or EPROMs (2764 up to 29C010) in the ROM
sockets
(2364, 23128, 23256) of Commodore computers. Depending on the size of
the original ROM and the Flash or EPROM that is used to replace it, up
to 16 ROM sets can be selected with an optional switch.
main page:
general information and configuration overview
PET2001 RAM/ROM adaptors
Very small adaptors to replace the
custom 6540 and 6550 display RAM/ROM chips in the original PET with
easily available replacement chips. Great as an addition to the RAM/ROM
expansion, but they also work without it.
main page:
contains all information about the project
PET/CBM Video Adaptor
A convenient way to connect an
external monitor to Commodore's first professional series of computers.
I mostly use it during repairs so I can put the internal monitor out of
the way.
main page:
contains all information about the project
A570 2MB RAM expansion
The Commodore A570 is a CD-ROM drive
that plugs into the A500 and A500+ to make it compatible with the
Commodore CDTV. The 2MB expansion plugs into the internal memory slot
and adds 2MB autoconfigure fast RAM.
main page:
currently only a short description and a prototype picture is available
Contact
If you have questions about this website, my projects or my products,
please mail me: please visit my contact
page.