Monday, September 28, 2009

8085 Trainer Project

I've posted a web page on my 8085 micro trainer that I'm building. I've posted instructions on building the system up just as I'm building it, along with my notes.

To date, I've posted instructions that go through getting the core system running with a memory, adding switch inputs through interrupts, and giving the 8085 an LCD display as an output. I'm presently integrating the LCD driver code with the interrupt code, then I'll add a keyboard to the system.

This system will be a small, hand-held micro trainer. It's intended for easy, anywhere machine language programming of an 8080-compatible system, for those of us who find such activities fun and relaxing.

Check it out >>

Yes, I do machine language programming for relaxation. I also crochet Irish lace and embroider knotwork patterns for relaxation. I like things that are mentally engaging, but that can proceed at a casual pace for unwinding at the end of the day.

In case I'm really fried at the end of the day, I keep databooks stacked on my bedside stand.

Have a look at my electronics web pages.

Wednesday, September 23, 2009

Mystery Computer Identified

The Mystery Computer that I blogged about yesterday has been identified. Thanks to the helpful folks at the Vintage Computer Forums.

The identity is revealed on the Mystery System's Web Page.

Meanwhile, an update to my website is getting closer. I've nearly finished the electronics section with a huge new addition of material, then the rest of the website is getting a once-over to improve appearance, usability, and to automatically whiten the smiles of readers while they peruse the contents.

Mystery Computer

I've got a couple of boards for a Z-80 SBC that I don't recognise. Take a look at the images at and tell me what you think if you recognize them.


Monday, September 21, 2009

8080A CPUs from NTE

I was in Fry's Electronics recently looking for some parts. I didn't find what I was looking for (non-volatile RAMs) but while I was looking I went through the catalog of parts they carry--the NTE semiconductor catalog.

You could have colored me shocked when I saw the 8080A and its support chips in that catalog! I looked around to make sure I hadn't slipped back 30 years to the Fry's grocery store with the "chips" aisle: potato chips on one side, semiconductors on the other.

What surprised me even more was that while the 8080A was there, the 8085 wasn't.

8085 circuit
A Relatively New 8085 IC in a Circuit Built Three Days Ago
8080A prices from NTE are about the same as 1978 or so, about $20US. In other words, they're at about post 6502 prices, but higher than the Jame-pak blowouts of the early 80's (about $2-3.)

Once you add a clock chip and control signal demux chip you're talking real money, especially today when a solid microcontroller comes in at a buck or less.

The real mystery to me is where these chips are being made. Is there some fab out there still cranking out 70's-era NMOS process wafers? On 2 or 3 inch? Or are these old production stockpiles? Or--heavens forbid--did someone bring the 8080A to a new process? Five-metal sub-micron 8080As, still rated for 2MHz, perhaps? I don't think so, but I never expected to walk into a Fry's in 2009 and find 8080As offered for retail sale, either.

I know the 8085 is still very popular in education, is it still in production? If so, I haven't found it. What keeps the 8080A in production? Does NTE have a supplier that keeps 30 year old fab equipment in his basement with a supply of wafers and a packaging setup in the spare bedroom?

Inquiring minds just can't help wondering...

Saturday, September 12, 2009

The Trailing Edge: A New PS2

The Time is Ripe

Last Friday we stopped in at our nearby Blockbuster video to pick up a couple of used movies. While we were there I noticed that it looked like they were blowing out their PS2 games. I didn't get any, as I had no PS2 to play them on. During the drive home my brain coupled this with the announcement of the newer, cheaper, slightly crippled version of the PS3 and it occured to me this might be a good time to pick up an inexpensive PS2, accessories, and game library.

Opportunity Knocks

This week I was in our local thrift store with my daughter on Thursday while she shopped. When we got to the checkout, there was a PS2 in the display case, bundled with a wireless controller, memory card, and cables for $50. I decided to get it even though it hadn't been tested, once I learned they had a guarantee on electronics. I also got a couple of games. Shadow of the Colossus is one of the games that's had me interested in the PS2 for a long time. The visual design, at least, looked like something to make the game an experience. I wanted a second game as well, for a break or in case SotC turned out not so good. Star Trek Encounters was the only other one I could see buying.

It's Alive!

Once the other events of the day allowed, we hooked it up to the big screen. It came up fine, we needed new batteries in the wireless controller but all else worked great as-is. The unit says it's a model 13001.

SotC spun up fine, and it wasn't long before the kids and I were soaking up the extremely lengthy intro video. After some time and a lot of riffing on the intro, we finally got to play. Having neglected the written directions, it took a while to figure out how to find the first enemy, and to satisfy ourselves that we didn't have a choice of encounters.

Goya's Colossus
You don't get to fight this guy in Shadow of the Colossus for PS2, but he's not far off from the ones you do fight.
Some time later, I and my oldest got frustrated with Shadow of the Colossus. We managed to get onto the first critter's leg, but were constantly stymied no matter what approach we took to get higher. I'd managed to get a bit higher on the leg through an apparent fluke, but neither of us could manage it again. After a bunch of gambits were tried, we got fed up and put in Star Trek.

Space, the Boring Frontier

OK, I'm all for tutorial levels in games, but when a modern game comes in as more patronizing and less interesting than something like Master of the Lamps from the Commodore 64, that's bad. MotL was a good game for its day, a mix of a fly-through-the-rings game and Simon with very nice graphics for the time as well. But today we're in a world where excellent puzzle/platformer games like Spyro the Dragon have raised the bar more than a little.

Encounter may turn out to be a good game, but I may never get past the fly-through-the-rings tutorial to find out. Frankly, I'd rather fire up Spyro on the PS1, which has more interesting ring puzzles and better controls.

Never Count Out the Small Fry

Afterward, we did a little web browsing to see what others recommended as the best games for the PS2. I knew I wanted Katamari Damacy, our browsing added Black (destructable environments was the selling point) and God of War (action, reports of good controls) to our short list of games.

Then my youngest decided to take a crack at Shadow of the Colossus. I'm not sure how, but it turned out she didn't get a chance to try it earlier. I left her with the controller and hit the sack. In the morning, she reported two kills.

The Dumpster Beats Us

Today I returned to Blockbuster. Either they sold out nearly all their PS2 games or, more likely, tossed the unsold stock after Labor Day. It was the same at another Blockbuster. And the bin of clearance games at K-Mart was gone. Best Buy had a selection of new games, but only a couple of pathetic clearance-priced games. I was beginning to wonder if I'd bought the PS2 a week too late.

We finished up some more mundane shopping, took it home, then set out on a longer trip to try Game Stop and Electronics Boutique, both about 50 miles from home.

Game Stop FTW

We hit Game Stop first. We looked at the racks of PS2 titles in the racks in the center of the store and were striking out. A rack of sports games had nothing of interest, either. There were enough titles that we could easily have missed something, so I kept looking while one daughter went to the counter to ask after the games we wanted. That turned out to be the key. There was an entirely different shelf of PS2 games near the counter--those worth owning. I hadn't even looked at it, I'd taken it for a customer holds shelf or something like.

We came away with all three games and a second wireless controller. After a little more shopping at stores nearby without locations nearer home, we headed for home to try out our new games.

Shadow, Second Attempt

First, I decided to take a second stab (so to speak) at Shadow of the Colossus. This time I was more careful of how I used the controls. I think my mistake the first time was trying to "jump" to higher handholds on the critter while pressing the direction control stick. Letting up on the stick while jumping and pressing the "hang on" button had the desired effect. After only two or three tries I managed to do what I'd failed at waay too many times the previous night.

If my kid hadn't managed it I might have given up on the game. I'm ready to take shots at Colossi 2-16 now.

Katamari Killer-App

We then tried out the new games. Black was tough for my oldest on her first go. I took over, and showed her that aiming through a combination of turning and "strafing" movement works best. She had a great time with God of War, however. I'm looking forward to playing it.

Katamari Damacy is amazing. It's silly, offbeat, and incedibly fun. It's got a wierd humor to it along the lines of the Wario games, but a bit more madcap and less body humor. I think they pitched it just right. The game is engaging--challenging while being simple. There are enough interesting side challenges and fun things in the levels to take a seemingly too-simple game and make it into something well worth spending the time to play.

Katamari Damacy is worth the price of the system all by itself.

The two-player game in it makes me glad I got the second controller, too.

I'm looking forward to seeing what else is on the shelf at Game Stop, and getting in to Electronics Boutique, as time goes on. I suspect the other Katamari titles and God of War II will be on my list.