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by joakleaf 3433 days ago
The demo was credited as 2017, so I don't think you can really use the bouncing ball or Wolf3D as reasons.

You could actually buy a speech synthesizer for the TI.

Yes, the demo is impressive compared to what else was available on the machine, but it actually had a (underutilized) 3 Mhz CPU and pretty advanced graphics system.

The TIs biggest problem was that it came with very little RAM, so you generally had to store application data in video memory or expansion cards, which made the machine incredibly slow.

More info about the demo here: http://hackaday.com/2017/01/30/dont-mess-with-texas-the-ti-9...

1 comments

OK for the 2017 demo, but the TMS9900 was slower than the Z80/6502 of the same time, because it was a 16-bit microprocessor with a 8-bit bus, and registers were mapped to the RAM. This demo required power, and is very far from all other TI99/4A games, and most of them were written in assembly (the basic was too slow). So I still think it's a fake, or it is running on a deeply modified emulator, or with hardware extensions listed in the wikipedia page * ) but it's not a "vanilla" TI/994A.

* https://en.wikipedia.org/wiki/Texas_Instruments_TI-99/4A

I don't have any problem believing this can run on real hardware. One of the programmers, Tursi, has done some amazing things that do indeed run on the real thing.

I'm not sure what you're counting as "vanilla", but a TI with the Speech Synthesizer and the 32K RAM expansion is vanilla to me. Those are utterly ubiquitous and period-correct OEM upgrades.

If it required the F18A, which is an FPGA implementation of the TMS9918 graphics chip with some significant new features on it, I'd agree that wouldn't count. That chip makes it a totally different graphics machine.

> TI with the Speech Synthesizer and the 32K RAM expansion is vanilla to me

Agree

> graphics chip with some significant new features on it, I'd agree that wouldn't count.

Agree too. If the graphics chip was so powerful, it's hard to understand why it was so underused, and not integrated in other microcomputers of this time. The video memory of the TI was 16KB, I had several computers with this size, and you couldn't render with this quality, even statically because at 256*192 it's less than 2,6 bits per pixel. And the number of sprites is more than impressive.

Actually the TMS9918 is used in a lot of places - in addition to the MSX (which I see you noted below) it was also used in the Colecovision game console and Sega's SG-1000 among others.

The sprite support was great, especially for the late 1970s. Though, I continue to be impressed with what an unencumbered architectire like the Apple II can do with sprites purely in software.

Sega actually kept going with the architecture - the Sega Master System used an upgraded 9918 based chip, and the Genesis/Mega Drive built further on top of that.

From Wikipedia: --- • Multicolor mode: 64×48 pixels (each pixel may be any color, all 32 sprites are available)

• Bitmap mode: 256×192 pixels (no more than two colors in an eight pixel row, full 15 color palette + transparent, all 32 sprites available)

• Graphics mode: 32×24 characters (256 8×8 user-definable characters, full 15 color palette + transparent and 32 sprites. ---

The last was the mode accessible from Basic and Extended Basic. I remember longing for the bitmap and multicolor mode.

For the 256x182 mode, the pixel bitmap is 5824 bytes bitmap, plus 1 byte for color info of each 8-pixel (4-bit foreground/4-bit background) which is also 5824 bytes. Total 11648 bytes. Just 2 bits per pixel BTW.

The TI994a had 32 sprites (all single colored 8x8 pixels). You could also magnify them.

Also from Wikipedia: --- The TMS9918 was the basis for the VDP chips in the Sega Master System, Game Gear and Mega Drive. They used additional display modes and registers, and added hardware scrolling capabilities and other advanced features. (Note that the Mega Drive VDP cannot access any of the TMS9918 display modes discussed below.) ---

Apparently the TMS9918 powered the MSX too, I will watch some demoes.
Download it and see for yourself.

http://www.pouet.net/prod.php?which=68783

That's an interesting proposition. I've installed MAME but I need to hunt for the BIOS.
I hear you regarding the speed... I had a TI and I learned to program on it, so I know how amazingly slow it was!

They do mention that they used extra RAM from the floppy drive controller which would help!

I don't see anything that makes me think it is completely impossible. Lots of the more complicated full screen effects could probably be made by altering character bitmaps (which was pretty fast). Parsec managed smooth horizontal scrolling back in the day, but I must admit some of the scrolling stuff definitely looked challenging to do on that machine. I still think, you can get far by manipulating character bitmaps, and clever use of sprites.

I still think calling it "fake" may be a bit harsh on the coders if it isn't.

Anyone tried it on one of the emulators?

A mistake on that article... the 32K RAM expansion is a separate card, not part of the floppy controller. They were almost always sold together, however.
Well, Parsec is very far from this demo, if the window is small it's for speed. The demo is full screen, which is impressive. And Parsec is coherent with what the hardware had to offer for the 3D those years, like Elite.
Parsec was 2D horizontal smooth scrolling. It wasn't full screen, but the scrolling screens in this demo generally contains repetitive graphics, which would allow them to use a number of possible tricks.

I actually downloaded and tried the demo on the Classic99 emulator, and it works exactly as advertised.

Would love to see actual hardware demo though.

check out another demo here by one of the coders of the megademo https://www.youtube.com/watch?v=Guv_Jp3m-vw this is video from my 99/4a screen real hw.. my boot menu is a gram device so it's a little different..
Same here, it works even with the F18A option disabled. So I apologize to these talented developers!
No problem ;)
I have the real hardware ready to go, but I don't currently have an easy option for getting software from the internet onto it. I see they made a ROM cartridge version of it; if they ever make a run of those for sale I'll definitely grab one.
you are in luck they are available soon as I get the labels in also many other new TI-99/4a games, expansions etc including 32k if you don't already have it
FYI, a kind member of the atariage forums will be burning carts for cheap. if anyone is interested just stop by the forums there.