TI's folly

[Retrospect]

Anyone notice they used the TI99 instead of TI99/4A?

The TI99 had a more crappy GROM and ROM so the game was much better on the TI99/4A.

I've often wondered about whether there are notable differences in games when played on a 99/4 (1979)

I just thought it was obvious things like lack of bitmap and different standard font. (Although I do know one thing, if you compile any program on the 4a that has a input parser, it will totally screw up when played on a /4)

[digdugnate]

while we're on this line of conversation- it seems like that with the 32k expansion some of the games appear to run smoother (noticeably ones like Slymoids).

 

Is this just in my head? lol

[+save2600]

while we're on this line of conversation- it seems like that with the 32k expansion some of the games appear to run smoother (noticeably ones like Slymoids).

 

Is this just in my head? lol

 

Yes.

[digdugnate]

ha! well, i guess i'll keep living in my fantasy world then.

[PeBo]

Most days I find it reassuring to simply have confirmation that there is SOMETHING in my head!

 

and a head full of fantasy is usually preferable to an overdose of reality.

[PeBo]

This is what they were going to make but for some reason it came out with no infra-red socket for wireless devices (joystick and keyboard were going to be wireless)

 

This is a prototype from 1978.

dim4.png

While missing the infrared of the Dimension 4 protype, the /4 model with the volume control and headphone jack is one of my 2 holy grail items (the other being a fully functional sidecar thermal printer with a few rolls of paper, but I'm pretty confident that I'll eventually find one of those)

 

This model of the /4 has shown up on eBay a couple times....last time at a really reasonable price, but I let both of them pass. One was in really rough shape and neither had a power supply, which of course is not the same as the later /4's or the /4A's power supply, and is itself a really rare commodity.

 

Anyone know what the production #'s (quantities) were on the volume control/headphone jack models??

[+Ksarul]

The ones with the volume controls have an internal speaker under the grille at the back of the cartridge port. There are not a lot of them out there. There is another potential issue: the external power supply has DC outputs--not AC like the rest of the TI family. A regular TI power supply will destroy it. . .

 

These consoles were only sold in Europe, and were all made during a six- to eight-week period at the very end of December 1979 through mid-February 1980, based on the manufacture dates I've seen over the years. It is possible that the period of manufacture was a little longer than that, but probably not too much. Considering that TI was only selling a couple of thousand units each month (worldwide, in all variants) at that time, I doubt that there were ever more than 1,000 of these in existence. The power supplies are a real limiter too, as less than half of the ones I've seen still have an original power supply. . .and even there you have to be really careful, as all of the power supplies are for 220V power--and are in the same large case as the first European AC-output power supplies. Extreme caution is paramount here. . .

[apersson850]

 

Would you please expand on this a little, I'm intrigued.

Well, I've installed 64 K RAM expansion inside the console. All on 16 bit wide bus, the fastest the TMS 9900 can utilize.

Normally, only 32 K RAM is seen by the CPU, but it's possible to enabled the other 32 K RAM too, 8 K at a time, to overlay internal addresses like operating system, DSR space, cartridge port and I/O ports. Enabling all gives a contiguous 64 K RAM, but then you can't access VDP, sound etcetera without disabling RAM covering addresses 8000H-9FFFH while doing so.

It's also possible to disable the 32 K RAM part which acts like the normal memory expansion. When doing that, the normal memory expansion, if present, is instead visible, so it's possible to have two separate 32 K RAM expansions present at the same time, but available for use one at a time.

All this switching between different memory blocks is done with I/O bits (CRU), which means it's all under software control.

[Omega-TI]

Hmm.. interesting. What kind of software have you written for it that takes advantage of it? I'm assuming you don't enable the entire 64K and disable the DSR space as you would never be able to load a pre-existing program.

[PeBo]

Anyone know what the production #'s (quantities) were on the volume control/headphone jack models??

 

The ones with the volume controls have an internal speaker under the grille at the back of the cartridge port. There are not a lot of them out there. There is another potential issue: the external power supply has DC outputs--not AC like the rest of the TI family. A regular TI power supply will destroy it. . .

 

These consoles were only sold in Europe, and were all made during a six- to eight-week period at the very end of December 1979 through mid-February 1980, based on the manufacture dates I've seen over the years. It is possible that the period of manufacture was a little longer than that, but probably not too much. Considering that TI was only selling a couple of thousand units each month (worldwide, in all variants) at that time, I doubt that there were ever more than 1,000 of these in existence. The power supplies are a real limiter too, as less than half of the ones I've seen still have an original power supply. . .and even there you have to be really careful, as all of the power supplies are for 220V power--and are in the same large case as the first European AC-output power supplies. Extreme caution is paramount here. . .

Someone posted the power supply all by itself a couple years ago, and I thought about buying it (just in case), but didn;t. Been kicking myself every time one of those models show up without one.

 

Not too concerned about the 220V DC...spent many years of my youth travelling for work and have quite a few convertors for bringing my equipment there or their's here (but I'd make certain before plugging it in to be sure!!)

[Retrospect]

That magazine advert, the one in 1982 in either computer weekly or C & VG, selling TI99/4 computers for £250 (console no monitor, UK ) ... I bet some of theirs went bang if and when they needed a new supply because they won't have known! ... Also he was selling the darn things without even mentioning the internal differences and no bitmap etc.