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Thanks for the kind words all! This was a long time in coming but we are SUPER happy with how it came out. Working on this machine was certainly a challenge but our coders can tell you more about that. The fantastic reception we got when it was presented at the party made it all worthwhile.



Yeah we couldn't get a video capture device to sync to the TI properly and ran out of time. The MAME emulation is "perfect" so the current one is a good reference video, but a hardware cap would be awesome.

@ti99uc: Nice! I think that's the third or fourth cartridge in existence. :D

Thought I'd write a little bit up on the genesis of this prod in case you guys are interested. We believe this is the first true demo/megademo on the TI99/4A, ever. Of course you have to be a little strict with the definition of a 'demo' to get that, but hey, it works for us. ;)

In 2014 I was visiting a foreign (to me) city, and found a dusty boxed TI99 in a pawn shop, buried under some hi-fi gear. I didn't buy it at the time, but I looked up if there had ever been a demoscene *anything* on it, and back then found nothing. That got me thinking. About six months later I moved to the same city, visited the same pawn shop, and haggled my way into very cheap TI ownership. At that point I asked Orbitaldecay if he was interested in something on it, and he absolutely was.

The original plan was a musicdisk (naturally my idea) or a simple scroller+effect+tune intro. The soundchip turned out to have a rather steep learning curve for me, and Orby & I were busy with some other prods. But the idea didn't go away. Sometime before @Party 2016, Orby got the ball rolling by getting RamonB5 interested and it was game on.

In the meantime 99tro by Frog got released, as well as some scene-ish but not quite "in the scene" stuff like Happy New Year 2015 by Asmusr (^^ see credits) so it was clear a simple intro would no longer cut it.

Fortunately, Orby and Ramon managed to recruit some of the best active devs on this platform, and once everyone was on board, after almost a year of hard work, here we are. Hopefully the results paid off. I personally am unbelievably proud of this thing, sure it's got a couple rough edges but for a platform first I think we set the bar at a pretty good height. Now the question is, who's gonna be the next challenger? :D

Some fun facts about the platform & this prod:
- We have the same sound & gfx chip as the MSX to work with, and a 16-bit CPU. That's awesome right? Well, the CPU is slow (3MHz) and *majorly* gimped by its 8-bit bus. It was never intended to go in this machine and it shows.
- An unexpanded TI has 256 bytes of general purpose "fast" RAM on that 8-bit bus. It also has 16k of video RAM but you can't use that for storing miscellaneous code or data. The usual add-on floppy controller gives you another 32k of *horrendously slow* RAM, and we ended up having to require that. It's there, it helps, but we still tried to avoid it as much as possible.
- The TI's built-in BASIC is slow and useless, and there's *no* ability to run inline assembly or compiled programs from disk. The assembler is supplied on a cartridge and requires the 32k RAM expansion. You can also get extended BASIC on a cartridge that is much better.
- You can run our demo direct from its own cartridge, or from disk using the "editor/assembler" cart, *or* from disk using an extended BASIC cart. That required three different loaders, but the choice is yours.
- Of the three main emulators that are around for this thing, two of them - Classic99 and JS99er - were made by members of the demo dev team, Tursi and Asmusr respectively. They have both since been updated to run all the scanline effects & general hackery that we needed to make this thing work, so go ahead and emulate. B)

Just to clarify things, we picked the theme *long* before the rise of the current macho political regime, and it has nothing to do with that. This is not a political demo at all. I *hate* having to even write this disclaimer, but what can you do.

("Don't mess with Texas" is a long-running anti-littering campaign that became a catchphrase. :)

Indeed, the whole Texas relates to Texas Instruments then anything else, no political reference at all.

A little info about the hardware specs to those who are wondering: as jmph mentioned, the sound chip and the VDP are the same as those which are present in the MSX. But rather than the 8 bit 3.58 Mhz Z80 we are spoiled with in the MSX, we have a 16 bit 3.0 Mhz TMS9900. 16 bit, that should be great, right?

Wrong. Each instruction on the TMS9900 takes on average around 15 - 30 clock cycles (!!) to execute plus the wait states for memory access and the 8 bit data bus and you have a painfully slow machine.

http://drolez.com/retro/ estimates it at about 0.1 - 0.2 MIPS. Compare that to about 0.43 MIPS for a 6502 running at 1 Mhz and about 0.58 MIPS for a Z80 @ 4 Mhz and you start to get the idea of how seriously under powered this machine really was (if you've ever coded for the MSX and are familiar with overrunning the VDP with the Z80, something to point out here is that the TMS9900 is too slow to overrun VDP!).

So naturally, we decided to write a demo about it :)

The only gotcha to the MIPs comparison is that the 9900 can do a lot more in one instruction than the 6502, thanks to a memory-to-memory architecture. You don't have to use registers at all for many instructions, and if you do, you get 16 general purpose registers at a time anywhere in RAM you want. But yeah, the machine isn't quick enough to overrun the VDP except in a couple of very contrived cases - mostly because of the 8-bit to 16-bit multiplexer which eats 4 cycles for every memory access. ;)

Exciting news! Should you happen to have a dusty TI sitting around and you wanna run this beast on your own hardware, you can conveniently order carts from Arcadeshopper.com! Well, they're backordered now, but you'll be able to soon. ;)

(Greg is a good guy, I've bought from him before. Note that this is being sold ~at cost with our permission.)

Hi all - I've uploaded my tune "Diagonals" from this demo to soundcloud. I've also included links to the source file and VGM file. Enjoy!
https://soundcloud.com/diagamblic/dya-diagonals-desire-dont-mess-with-texas-demo-ti99-4a

^^ You need the 32k expansion for the TI or it won't run. If you want to build your own cart you can order either the 512k (red) PCB or UberGROM board (blue) from arcadeshopper.com & use your 512k EPROM - or you can just buy a premade cart from there too. :)