Wednesday, April 20, 2005

Space Raider - update

Last night I got a bit further. I fixed up the cocktail mode, and decoded all the dip switches except one. I also found and decoded the bits which control the scroll speed and direction of the starfield. Finally, I found a "hidden" test mode while disassembling some of the code. (Hold down the fire button while resetting the game.) The todo list is getting shorter...!

Sunday, April 17, 2005

Space Raider graphics fixes

I got my JAMMA cabinet running again, built the Space Raider-to-JAMMA adapter, and got the board up and running over the weekend. This allowed me to fix most of the graphics problems with the driver! (Most notably, the grid is animating properly now, and it's the right color.)

The only thing that's noticable now is the lack of a background starfield. Without schematics, this will probably take a long time to get right.

Sunday, April 10, 2005

Atom syndication and blogger formatting

I'm not sure why my paragraph breaks are only showing up "sometimes" in the atom syndication of this blog. If someone has a clue, I'd love to hear it. I think it might have to do with whether I'm editing in HTML mode or not. Oh well, what do I expect for free... :)

The Car of the Future

This weekend, I had the pleasure of test-driving a 2005 Toyota Prius.

For those who don't know, this is a hybrid vehicle built from the ground up by Toyota. The engineering that has gone into this car is amazing. It has an internal combustion engine, and 2 electric motor/generators. They are connected to the wheels by an innovative planetary gear arrangement, which is basically simpler than an automatic transmission, yet has all the benefits of a continuously-variable transmission. There are other hybrid vehicles available, but as far as I know this system is the only one that's not really an "electrically-augmented internal combustion vehicle", with the exception of the Honda Insight which is a 2-seater. Toyota will be putting it into their Highlander SUV this summer.

For many more details and pictures, I recommend the web site of a Prius owner.

The strangest thing about this car is getting going. Insert your key fob into a slot on the dash, hold down the brake, and push the power button on the dash. The shift-by-wire control is built into the dash as well, so you simply temporarily move the knob to D for drive, and away you go. After that, everything is surprisingly normal - except it's almost silent until the engine turns on. The gasoline engine turns on and off as engine load or electrical loads demand. The window sticker says 60mpg city and 51mpg highway, and even though you'll probably never see those numbers in real life - I think you'll get 40-50 mpg in city driving no matter what. Oh yes, and emissions are reduced by 90% over a conventional vehicle.

It seems to have plenty of power. Although it's not meant as a performance vehicle, you have no trouble whatsoever merging into freeway traffic, for example. It's also got plenty of room - bigger than a compact car.

Right now as they ramp up production - they can't make enough of these cars. I just happened to get to my dealer when one showed up, and there were people in line behind me to buy it. Even at sticker price from $22K to $26.6K, these are very reasonable cars and look pretty distinctive as well.

I ended up buying a Corolla instead, but not because of any shortcomings of the Prius. It was a choice between the high-end Prius which had a bunch of gadgets I don't need, and a $17K car which would do exactly what I needed. Still, I can't help but believe that my next car will be a hybrid.

Thursday, April 07, 2005

Space Raider

I first worked on this driver last year, after Pierpaolo started it. (It's currently playable, but there are plenty of graphics glitches.) Unfortunately, I was unable to make any further progress without access to the physical hardware.

So, now I have the Space Raider board on my workbench, and I'm slowly making progress. It's amazing what one person can do with a multimeter, some databooks, and time. :)

Right now I'm concentrating on the I/O section for the sound cpu. In case anyone's interested, this is how I'm proceeding. First, I found the 5 sound chips and backtraced them to the address decoder for all the IO ports. Now I'm going through ports 0x28-0x2f, 0x30, and 0x38 and figuring out which bits are being used and for what purpose. Ports 0x30 and 0x38 go to a bank of 8 4051 analog mux IC's. They each have graduated resistor ladders connected to them. Maybe they are a fancy volume control or an analog filter. I should be able to get that figured out soon.

Additionally, I'm making up a harness to use to power up the board. I discovered, and they had everything I needed for <$15. I'm hopeful that I can get a lot more information by actually playing the game! :) It will be very nice to get the grid behavior correct.

Wednesday, April 06, 2005


I've had some strange thoughts lately about pirates. It came to a head while watching the "Pirate Party" on board the Disney cruise line.

First of all, I am a fan of Neal Stephenson and am currently reading "Quicksilver". Among many other things, there are pirates in there, as it takes place during the late 17th and early 18th centuries.

These were really bad guys. They were sort of like terrorists are today. It took the resources of whole countries to finally get rid of them.

Strangely, children dress up as pirates today. On the cruise, there was a pirate party with pirate costumes and dancing. And this was right in Blackbeard's old neighborhood, as I understand it.

I can't imagine my great-grandchildren dressing up as terrorists for Halloween. It would be nice to think that the problem will be so obsolete by then that it could be possible.

Ok, that's wierd you say. But it doesn't end there.

The Pirate party is clearly inspired by the "Pirates of the Caribbean" movie and ride, an important part of Disney's intellectual property.

But wait - the term piracy now refers to people who steal intellectual property! This is actually something companies like Disney are deathly afraid of today.

So, let me get this straight - the original pirates who murdered, raped, etc. are trivialized/stylized by children and everyone else. Meanwhile, the word pirate refers to people who copy DVD's, and now it's their turn to be stopped by governments and multinational corporations.

So maybe I've got it wrong. Maybe my great grand-kids will dress up as I.P. pirates. That would be much cooler than terrorists. :)

Cruise Review

Well, I went on the Disney Cruise over this past weekend - so I thought I'd post a short review.

First of all, I want to say that I'm not a big fan of the Disney corporation. I abslolutely hate what they've done to U.S. copyright law. Still, this was probably my only chance to go on a cruise with my family, so I have to deal with the guilt now. Maybe a big fat donation to the EFF will make me feel better.

I gotta say, Disney knows how to put on a cruise. They had everything an adult would want, but also everything kids like. For example, they've got adults-only bars, an adults-only pool, and gourmet food - along with tons of kids activities, foods, pools, etc.

The staff members must be trained to try to help when they hear a kid crying. They were very attentive and entertaining.

The shows were more oriented towards kids, so I didn't get a lot out of them. I believe I described one of them as a "nice review of the intellectual property portfolio" and got a funny look from my wife.

There were stops in Nassua in the Bahamas and Disney's private island "Castaway Cay". They were both nice and much warmer than Michigan :)

The only drawback I ran into was that my son is a little young (3) to enjoy everything they have. For example, they have a play/activities area which you can leave your child in, and they will page you when he/she wants to leave. My son was a bit too shy to be comfortable there without me - but my 7 year old niece never wanted to leave. When my son turns 5 or so, it would be perfect trip.

Fun with FPGAs - recreating the Atari TIA, Part 1

I have been playing with recreating the Atari TIA chip as used in the original 2600 in an FPGA.  I know this has been done a few times alrea...