Latest Project News
March 13, 2007 : Yep, its been a while since my last update. I just finished off a major revamping of the website. I'll be cleaning up content over the next few days...
General Update on What's Going On
August 31, 2004 : Busy, busy, busy... Now that the new workshop has been completed, and I have a place to work, lots of things are in progress. Learning how to make Printed Circuit Boards (PCBs) has been high on my list for quite a while. Recently I did produce a very simple board using the photographic method and some planning. Lots of details to understand, but if you climb the hill one step at a time, you will reach the top. I recommend a book titled "Build Your Own Printed Circuit Board" if you have the desire...
Another time consuming activity is my recent post of a bunch of Altera UP2 board projects (see below). Lots of good stuff to look at. In my spare time I have been studying the schematics of the Atari 800 and reading through patents. Speaking as a true geek I can safely say this stuff is cool! Along my journey I will have to confront some analog stuff (curses!), specifically composite video generation. Luckily, lots of good references on the web can be found. I see transistors in my future.
Atari 800 Antic II Under Way
August 21, 2004: I'm am absolutely fascinated with retro computers and games. In many cases they are simple enough for one person to fully understand, yet complex enough to enjoy studying and learning how they really worked. They are usually designed around limited resource constraints that require the hardware engineer to really know their stuff.
Lately, I have been absorbed with how video was done on some of the more interesting machines such as the Vic-20, Atari 400/800 and the Amiga. Those machines, in my opinion, encapsulated some of the breakthrough technology of the times. I would dare to say that the Amiga is really an Atari 800 on steroids!
In the course of my pursuit, I stumbled upon original Atari Technical Documents for several of the main custom chips. They have been posted here for download. Note: They are "big" as they are PDF files loaded with scanned pages.
Altera UP2 Projects Galore
August 31, 2004: I am finishing off teaching a class on programmable logic design and synthesis using a really good book titled "Rapid Prototyping of Digital Systems". The book contains a whole host of computer/cpu oriented projects that were designed in Altera's MAX+PLUS II environment utilizing Altera's UP development board. During this course I moved all the code into newer style Quartus projects and fixed some issues. You can download the entire project archive here.
February 26, 2004 : Wow! Its been a while since I've updated the site, but rest assured lots of stuff has been going on behind the scenes. These months have been spent taking VLSI design classes, designing with wells, poly and metal to build transistors, gates, cells, and finally chips. Wow I'm back to VHDL again, it's nice to be home. If you're into VLSI design, check out the freebie "LASI" and "Electric" software. Really good stuff.
Also in progress is the construction of a professional work area to ease the building of projects (pictures to be posted soon). Thanks for the nice emails concerning the posted projects. I can't always answer specific questions related to them, but it's nice to see them being downloaded and dissected!
A First Look at the Burched B5-X300 FPGA Board
September 4, 2003 : Recently I've had the luxury of trying out the new Burched B5-X300 board equipped with a Xilinx XC2S300E fpga. The board came delivered with full schematics. It's up to the user to configure it! At first the task is a little daunting, but this board appears to worth the effort. It is very configurable. I hope to start posting some design examples using this board soon... stay tuned.
XSOC VGA Controller Fix
June 17, 2003: SDRAM is just plain cool, so much memory, so little space... But if your memory controller isn't all that reliable, well then just give me plain old SRAM! To get to the point, an early version of XESS's SDRAM controller must of had some issues, because an update has been posted at the XESS site. It has solved my main design problem of unreliable startup operation after design download. If you are using the SDRAM controller, make sure to check your version. (The project xsocVGABitmap posted on this site has been updated as a result of discovering this information.)
Two New XSOC VGA Projects
June 7, 2003 : Working examples on how to access SDRAM and a good simple example on how to create a mixed HDL language (Verilog and VHDL) design with the Xilinx tools. See projects page for details.
VGA Video and Micro8 Projects Updated
May 26, 2003 : The Micro8 for the Xess board project has been updated with a newer CPU. John Kent has been hard at work with the Micro8. Just recently he added some video capabilities using some of the video projects found on this site. I hope to have an XESS version of this new project shortly.... Also the VGA character generator project has been updated with files for the Xilinx Core Generator and some documentation on how to use it.
XST-2 XStend V2.0.0 Board Upgrade!
May 20, 2003 : I just extended my XStend board! Using the RLC-1 RS232 to 3-5 Volt Level Converter available from DigitalNemesis I was able to add a second RS232 interface to my setup. Why? Because the XStend board is wired in such a way that makes using both SRAM memory and the RS232 interface at the same time nearly impossible (it would be an act of digital magic!).
The upgrade was easy. Using available power supplied on the XStend board, and input/output pins available on the fpga the interface was soldered into place in about an hour. Testing was done with the rs232 project available on this site. This upgrade allowed me to run the Micro8 design available at John Kent's fpga site (see references and projects for XSA version of his project).
May 13, 2003 : If you should find this site while surfing the web, be sure to drop an email my way. This site is dedicated to publishing interesting FPGA projects and other useful information related to the design of computer hardware. All of the projects posted are written in VHDL and/or Verilog. As of right now, all of the projects are for the Xilinx based XESS XSA-100 board.
Many designs can be "ported" to other boards by simply redefining FPGA I/O pin locations. Some will require more substantial surgery in the form of changing device primitives. I am very much a novice FPGA programmer, I've only been involved with this aspect of designing computer hardware for about a year. This is also my first FPGA development board.
My driving interest in this area is in building a full-up computer system on a single FPGA. Lots of pieces and parts exist on the web, but I have found a lack of "simple" projects for the novice to study and learn from. I hope some of the projects posted on this site help solve that problem. Let me know!