Data Airlines » Tech

Razor 1911 – Votedisk

Data Airlines — Wed, 27 Apr 2011 09:14:08 +0000

The almost 20 year old tradition of a big German demoparty during the Easter-weekend continues, after Mekka Symposium and Breakpoint it is Revisions turn to gather almost 1000 alcoholized nerds from all over Europe to perform strange ceremonies. As usual, Razor 1911 was present and also competed in the 64kb intro category with an intro called “We accidently borrowed your votedisk” that coded by Rez with music by Dubmood. This time made by an old softsynth for 64kintros created by german demogroup farbrausch. Pretty impressing if you consider that it is all stuffed into 64kb we must say! Check it out on pouet.net here.

LittleFM on GBC

Nitro2k01 — Fri, 12 Mar 2010 04:49:05 +0000

I finally felt motivated to work a little on LittleFM, and the next feature in the pipeline was (the comparitively small) feature of “real” GBC support, ie support for double speed and colour palettes in LSDj which LittleFM has been lacking so far. (Instead it used the oldschool compatibility mode which didn’t allow LSDj to take advantage of the higher CPU speed found in the GBC)

It works great and flashing takes about half the time when done in double speed mode, however I forgot to clear the secondary GBC bakground map when going from LSDj back into LFM, using the classic sel-start-B-A combo. What this means is that the colour pattern from LSDj will not be erased but remain on the screen. This gave this nice visual bug seen below. As you can see, the pattern resembles LSDj’s screen layout.

I’m going to finish one more feature before I release LittleFM 0.4, loading and saving of individual LSDj files, so LFM can truly replace the builtin file manager that comes with LSDj. I have an almost working version of this feature, but it has wrinkles which I want to iron out before releasing it.

The last picture is shitwave which actually looks marvellous with the backgrounds residue. It gives the vibrations more life and you can see what’s actually happenening rather than just vaguely vibrating lines. It may not be apparent on the still image, but it looks nice live.

Sorry for the long wait, but have patience!

Shitwave synced to LSDj

Nitro2k01 — Thu, 25 Feb 2010 04:59:15 +0000

Another Gameboy genius, NeX is at it again. What he has done is to connect the clock output from LSDj to 74161 and 4024 counters then that is sent through (what I assume is) a slewrate limiter kind of thing to control attack and decay. Then that signal iscontrolling the frequency of a LTC1799 variable oscillator which is contralling the clock frequency of the DMG running Shitwave. (Don’t forget that Shitwave sucks though!)

Notice how there’s an interference pattern with the screen update frequency and the left boy. And that this pattern oscillates at different frequencies as the clock speed is being modulated.

Plastik – Reaktor FM synth

Nitro2k01 — Sat, 23 Jan 2010 03:41:20 +0000

Plastik is an FM synth (or more accurately phase modulation synth) inspired by the Yamaha OPL chips found in Ad Lib and Sound Blaster soundcards in the 80′s and 90′s, renowned for its plastic sound. It should be noted, however, that even though Plastik was made to produce the same overall qualities as the OPL chips, and even has some of its unique features (the waveforms, the fixed vibrato and tremolo frequencies) it makes no claim whatsoever to be a complete or accurate OPL emulator.

Plastik is still work in progress, so if you find something that’s wrong with it, or you have a feature request, feel free to contact me. (Leave a comment or fetch my e-mail address from the bottom of the page.)

Download

(Not yet) frequently asked questions

Q: .ism?
A: .ism is the file extension for Reaktor instruments. You need Native Instruments Reaktor in order to try Plastik.

Q: How does the signal routing work?
A: There are four FM operators connected in cascade. Operator 1 can modulate operator 2 can modulate operator 3 can modulate operator 4. This is controlled by the PhM->x switch. Apart from that, each operator can also be broken out to the summing bus.

Q: Why doesn’t it sound like an OPL chip?
A: Because it isn’t an OPL chip. (And doesn’t aim to sound exactly like one. It’s an OPL inspired synth, not an OPL emulator)

Q: Dude, where are the filters??
A: There are no filters, use FM to shape the sound. (Or add a filter of your choice, this is Reaktor after all.)

Q: Why is it so ugly?
A: I will add a fancy schmancy skin for 1.1.

Q: Why an instrument (.ism) instead of ensemble? (.ens)
A: If everything needed to run the synth is already in the instrument why distribute an ensemble which is basically just another container in that case…?

S Like Suska

Dubmood — Sat, 16 Jan 2010 05:00:20 +0000

On the internet there is a guy named Wolfgang who got the idea to construct a fully functional Atari STe. What I get from the projects web-site is that his intention is also to comercialise it. So If I have got this right, he is using a FPGA to emulate all chips (yes including the ym2149) like the 68k cpu and the blitter and dma chips on a circuitboard and its running emuTOS. Its all opensource too. So yeah practically an open source atariSTe. At the moment it is not that priceworthy though since it costs about half of what a real STe would have cost back in the days, and about 5 times what it would cost today. But still, look at this cute little version of the motherboard. Suska III-T. It has:

128MB DDR RAM.
32MB Flash PROM.
2 Micro SD-Card plugs
Soundsystem with an audio codec.
RTC.
Radio chip.
Connector for a LCD panel.
Touchpanel ready.
Extension plug for the FPGA board.

We will follow this project with great interest yes sirs.

A brief history of the Atari ST.

Dubmood — Wed, 13 Jan 2010 05:32:13 +0000

A brief history of the ST.

By ChrisTOS – This Article is taken with permission from Low Rez issue #2

The Atari ST was unveiled to the public In January 1985 at the CES in Las Vegas. To see what the ST was though, we need to go one year back, to the ousting of Jack Tramiel from the company he founded, Commodore. We’ll skip the intrigue that surrounds that event and we’ll just say that Jack didn’t go alone, but also brought with him the engineer behind the 64, Shiraj Shivji.

When Jack lost his position at Commodore, he founded a company called Tramiel Technologies and Shiraj Shivji started working on a new 16-bit machine. How far the development had gone is at this moment unknown. What we know for a fact was that, as per the Atari Historical Society’s documents [1] and as dadhacker describes in his blog [2], he bought Atari with the dream to make this new computer that would bring the 16-bit revolution in power but without the price. That computer would eventually become the ST, we all know and love, but since the details are sketchy to say the least, Low Res decided to boldly go to the one person that knows more about Atari than Atari ever knew for itself.

The original 520 ST*

Curt Vendel is the man that created the Atari museum, founded Legacy engineering [3] and got the new Atari reinterested in their legacy with the Flashback 1 and 2 consoles. If there is one person respected and admired by all Atari fans, regardless of their favourite poison that would be him. We are therefore honoured that he agreed to answer a few questions.

Low Res: We’ve read the descriptions of dadhacker, who worked in TOS development but from those we can’t tell if the Tramiels had come to Atari with just an idea of a computer or if its development had already reached a good level. Rumour has it that it was the Amiga deal and Lorraine that actually forced Atari’s hand in both the ST’s design and the rush to the market. Are those two rumours true and if so to which extend?

Curt Vendel: Those rumors are completely false. Tramiel setup shop in May of 1984 in some office space in California where Shiraz went to work on his design for a new low cost computer (Codenamed – “RBP” for Rock Bottom Price). The Tramiels knew nothing about the existing contract between Warner owned Atari Inc and Amiga Corp, this relationship had been on going since late 1983 and Atari and Amiga went into contract in late Feb 1984 and paid Amiga an upfront advance of $500,000 towards the development of the Amiga chipset. Amiga would then receive $3mill from a stock buy by Atari when Amiga delivered the chipset to Atari at the end of June 1984.

Low Res: When was the Atari ST sent to the production lines?

Curt Vendel: “RBP” was in design and development within Atari from July 1984 through its showing at the 1985 Winter CES were it was shown to the public. Through the spring of 1985 the custom chips were being finalized and initial runs of the chips were made in May & June. Atari User Groups and Developers received small quantities of sample units in June 1985. Full production began in July through August 1985 and Retailers began to see shipments in late September 1985.

To speed up time to market, the “TOS” (The Operating System, or Tramiel Operating System) was initially delivered on diskettes as the new OS rom chips were not masked and ready in time for production release.

Low Res: You’ve written in the Atari Age forum that the ST was to be fitted with the AMY chip but instead it got the YM 2149. Were there any other corners cut in a bid to rush to the market? Was the ST supposed to have more such as hardware scrolling, sprites etc?

Curt Vendel: I wouldn’t called them “cutting corners” it was more of a strategic decision. AMY was and even today, still is a very remarkable audio chip design. However it still had bugs in its designs and time was running out to get it ironed out and then integrated into the ST design, so it was moved to be put into an XE series computer – however it would never make it into that computer design either. “SHIFTER” and “GLUE” were pretty much unchanged in their features and designs from what Shiraz envisioned them to what came out, so with that and from engineering notes and internal emails, it doesn’t appear that graphics features were cut back on in the initial design.

Low Res: The ST was marketed as a rival to the Macintosh, and truth be told it was a better machine. The result proved the Tramiels right since only the “business machines” survived, but what was the rationale behind it?

C.V. : Everything became a casualty of the X86 Win/PC machines. Once Windows 3.1 came out, it began to spell the doom for most computer platforms that were not X86/Windows. Even Apple in the 1990’s nearly went under and came close to stepping out of the PC business. The ST’s however had a simple design with intelligent features like a PC compatible disk drive design, color graphics, decent sound and built in ports for all basic needs from a computer user. Its ASCI port was actually SCSI done slightly better as devices self-assigned ID’s to themselves. Overall the ST was a good machine.

LR:The ST case design is.. interesting. Somebody thought to put the joystick ports underneath the keyboard. What were they thinking?

C.V.: I was never a fan of the Gray cased ST/XE look. It was so foreign to what Atari products looked like and should look like. Cost wise- doing an all in one case may be good, but visually I found it ugly. These are my own personal opinions of course. Yes the positioning of the joystick/mouse ports was a poor/clumsy choice, but given that most space around the sides was already occupied, there wasn’t much choice. I gained a lot more respect for the ST’s when the Mega ST line of “pizza box” styled systems and hard drives. It was an attractive look. Most importantly – a detachable keyboard that everyone wanted and expected in a computer by that time. Of course then the design went back to the 1040ST styled case again. The Mega Ste and TT030 were unusual looking systems, they had a unique look to them. I did like the fact that the TT030 came in an off-white appearance, it was much more pleasant looking then the dull gray color.

LR: Any other interesting insight we forgot to ask?

C.V: I think you asked some good questions.

TOS, The Operating System or Tramiel Operating System as it has been nicknamed was developed in a very short time on an Apple Lisa and in the offices of Digital Research. Anyone with any OS experience from Atari was sent there, they were given the x86 source code and the giant hack that is TOS became a reality. The descriptions of working there are an interesting read. Go to dadhacker’s blog and read them.

Atari actively marketed the Atari ST as a Mac beater and an IBM undertaker but unfortunately that didn’t really take off. The war would be with the Amiga. Atari had the fame of a home computer maker, at least in the United States and so had Commodore.

Ads like this:

would do little to change the climate and the first battle with the Amiga would be on the TV set of a show called computer chronicles[5]. The war that included various schoolyard battles, angry magazine writing campaigns and other favourite childhood memories was started then and ended… well it pretty much goes oon various internet forums where grown men (and women) can be kids again and behave like such .

Links

1. Atari Museum
2. Dad hacker blog
3. Legacy engineering
4. Atari ST vs Amiga*ST image compliments of the Atari museum.

Mr Roboto’s Arcade

MMN-O — Wed, 06 Jan 2010 22:13:58 +0000

It’s late Friday night and your mind is mush. You’re afraid that playing
your old NES would finally break it beyond the point where it can be fixed
by blowing into the cartridge. You find a dark brown, wooden chest stowed
away against the wall, with a spherical panda on top of it. You displace the
panda and open the chest.

Inside is, constructed using a trashed laptop mounted into the classical
chest, an arcade machine which resembles none other. Booting this laptop
will bring up a welcoming screen and game field for Mr Roboto’s Arcade…
And hey – there’s an enticing big, red panic button too!

Yes, the logo has alpha transparency and more than 16 simultaneous colours.
But it looks cool!

Located next to a sliced and diced, ancient Swedish military DL40 phone
switch in a livingroom up in Umeå, Sweden you can find this great
construction which will sooth your retro gaming needs. It grants a warm,
fuzzy feeling in the otherwise dark winter where the climate offers a harsh
environment, often far, far below freezing.

Of course you should own a copy of the game before playing. Ahem.

The laptop (hidden behind its own monitor) runs Ubuntu Linux modified
to boot up into a self-hacked menu system (using PyGame) where you play
a character from the Bubble Bobble game.

To launch a specific gaming console emulator, use your character to jump
and shoot small purple balls on it. You are then presented with a long list
of games available which are scrolled through and played with any
USB-connected controller. A little notice in the upper right corner shows
you the current console.

Game console menu and the big, red panic button.

Whenever you feel like it, you can throw yourself over the big, red panic
button. It’s hooked up to the USB controller of an old, long gone,
IBM keyboard and has been mapped to the Esc-key. Hitting it with great
force will immediately, at any time, return you to the main console menu.
This comes in handy whenever frustration reaches a certain level,
or playing against opponents who simply brag too much…

To turn off the arcade machine, your menu character has to jump around
and find hidden steps to stand on. One of those are for example on
Mr Roboto’s camera. A mysterious blob located off-screen in the
upper-right playing field has to be shot twice in order to end this joyous
experience.

2 player mode is supported. Pandas are bad winners, mind you.

Next up in the project is probably hooking up the arcade machine to a
projector instead of the original laptop monitor. Anything to boost
pixel size. Adding further console emulators to the list is also a given,
of course.

Then who made it? Ludvig Widman, homebrew hacker and electronics
hobbyist. He’s got more specs on his own site.

Written for Data Airlines by Mikael “MMN-o” Nordfeldth.

Low Rez #2

Dubmood — Fri, 01 Jan 2010 15:32:03 +0000

There is this new diskmag/blog/ezine about various retrocomputing subjects on the internet called Low Rez. There is alot of Atari ST related articles in it including interviews with important ppl throughout Atari STs 25 year long history. Who designed thoose tilted Function buttons? How did the ST vs Amiga war start? What went down at Altpart09? Read all about it, oh and try to look beyond the cover-art… or just simply dont judge low rez #2 by its cover.

Green Gameboy backlight

Nitro2k01 — Sun, 06 Dec 2009 14:51:12 +0000

(Most photos have Flickr notes. If you click on any of the pictures, you’ll go to that photo’s Flickr page where you can watch notes for the photos that have them.)
I’ve playing around a lot with DMG backlight lately. After I tried out the inversion hack on my guinea pig boy, I installed the hack on my regular one as well, but without a switch, and flipped the polarization layer of course. (The whole point of the hack is to uninvert the screen after flipping the polarization layer) This gave it more contrast, but then Bibin gave me a tip that so called “kelly green” coloured LEDs would work perfectly for a DMG backlight when using the inverse polarization layout, since the dark areas would completely block that green wavelength, whereas a large portion of white light will pass through even the dark areas. I believe that “kelly green” is the same LED type as “true green”. The LEDs in this eBay auction are suitable for the job, if you want to build your own backlight using this method.

Compare the images below:

The left picture is a Nonfinite backlight with an inverted polarizer. (And of course a 74hc04 screen inverter to uninvert the image) It has white LEDs which is atcually a bad idea for use with a monochrome LCD. Light pixels will conduct all wavelengths of light pretty evenly. Dark pixels on the other hand block green light but will still pass through a considerable amount of blue light. Add to that the white LEDs commonly used are actually blue LEDs with phosphor to produce other wavelengths. Read about it on Wikipedia. Because of this, white LEDs will have a much higher concentration of blue light compared to other wavelengths, which doesn’t exactly help getting contrast and gives the dark areas this purple colour. When using the green LED on the other hand, you only get one wavelength of light, which is almost perfectly blocked by dark pixels, giving you great contrast.

LED circuit board

For this chapter of my epic eternal backlight saga I used three LEDs from a batch I recently acquired, combined with layers from a backlight taken from a broken laptop screen. The LEDs are surface mount 45° wide angle

I needed a circuit board to keep the LEDs in place. It seemed like a waste to make a printed board a one-off piece of such a simple board, so I simply cut the needed traces and soldered components onto a copper laminate. I connected it to the screen daughterboard with a relatively thick single strand wire which also keeps the board in position.

The layers

And so a word about the layers used behind the screen… Lightboy made a thread on 8bc describing his backlight method. When seeing his desciption of the layers I was unsure what the layers were, but now that I have a complete backlight unit from a computer screen I have investigated the layers, so here’s an explanation of what the different layers are.

The bottom layer, not pictured, is the reflection layer. In this screen it was blank white plastic, as opposed to a silver colored mirror. The next layer, as pictured above, is the diffusion layer. Its job is to lead the light from the light source at the side and distribute it evenly upwards. It does so by small bumps in the bottom of the layer. The world has seen better Dremel jobs, but I suppose it works. This layer is also a couple millimeters thick, which created problems, see the bottom of the post.

The top picture may look like something straight out of The Twilight Zone, but it’s in fact my favorite layer of the five, the growth foil. What it does, as far as I can tell, is to collect light from two directions and send it up. There are two versions of this layer stacked, one that collects light vertically and one thta collects light horizontally. The top picture is me holding one hand in front of a lamp, which the layer duplicates because it collects light from two directions. I ought to cut of pieces of those layers and make trippy sunglasses out of them. :D

The blur foil is simply a foil of “brushed” plastic to even out the light distribution.

The topmost layer is the polarizing layer. To understand what this layer does you need to understand what polarization is and how it works. Read about it on nobelprize.org.

The final result

I’m not really satisfied with the outcome. This backlight has a flaw… The diffusion layer is too thick, which creates pressure on the LCD and creates differences in contrast in the areas that are under stress. And the layers are unaligned, creating a dark gap in the top of the screen. I can fix all those things however, and when that’s done I think this is the backlight design I’ll finally stick with.
I will also try to see if I can replace the white LEDs in my Nonfinite backlight panel, to use the green ones I have now.

Artfolder: MUSIK AUS DER BATTERIE

Erik — Sat, 05 Dec 2009 22:01:53 +0000

The first impulse for this project was certain dynamics, which occurred through intentionally causing defects in electronic toy pianos. It was the discovery of unexplored resources in small, cheap sound chips. Unfortunately, over time the dynamics got stronger and the possibilities of manipulation and modulation smaller, until finally the chips were completely destroyed. The low voltage method allows easier access to those resources without causing any damages to the equipment. These chips are able to make musical decisions and compositions. They just need to be stimulated to get it.

Visit Musik aus der Batterie on myspace.com. and Project Website