TI-99/4A's death in Halt & Catch Fire

[S1500]

So a hamster wheel went off in my head during tonight's episode:

 

1. A "bottleneck" for memory or something - anyone elaborate?

2. The joke of the users saying part of it can be used as a coffee warmer.

 

Then I realized what company the character worked for: Texas Instruments.

 

Then I heard the suggestion from Gordon's wife to kill off the computer.

 

Yes, the demise of our favorite home computer was a segment in a fictional TV show.

 

Wow, right in the feels.

[bennybingo]

Nothing beats a spoiler...

[Willsy]

Yeah I've been meaning to try and download a torrent of that series, as I'll never get to see it in Europe, I'm sure.

[nsxwolf]

So a hamster wheel went off in my head during tonight's episode:

 

1. A "bottleneck" for memory or something - anyone elaborate?

2. The joke of the users saying part of it can be used as a coffee warmer.

 

Then I realized what company the character worked for: Texas Instruments.

 

Then I heard the suggestion from Gordon's wife to kill off the computer.

 

Yes, the demise of our favorite home computer was a segment in a fictional TV show.

 

Wow, right in the feels.

 

It sounded like they were referring to the 256 byte "scratchpad" area, which was the only RAM available on the 16 bit bus. The rest was on the 8 bit bus, which meant the TMS9900 couldn't live up to its potential. Although, it seems like *that* was the bottleneck, not the 256 bytes of fast RAM.

 

Did people really complain that much about the power supply? I know they would get warm, but it didn't seem like a problem that would doom a computer.

 

Definitely not a scene I ever expected to see on television, though. It would have really been something if they'd included a TI-99/8 prototype on the conference table.

[nsxwolf]

So a hamster wheel went off in my head during tonight's episode:

 

1. A "bottleneck" for memory or something - anyone elaborate?

2. The joke of the users saying part of it can be used as a coffee warmer.

 

Then I realized what company the character worked for: Texas Instruments.

 

Then I heard the suggestion from Gordon's wife to kill off the computer.

 

Yes, the demise of our favorite home computer was a segment in a fictional TV show.

 

Wow, right in the feels.

 

It sounded like they were referring to the 256 byte "scratchpad" area, which was the only RAM available on the 16 bit bus. The rest was on the 8 bit bus, which meant the TMS9900 couldn't live up to its potential. Although, it seems like *that* was the bottleneck, not the 256 bytes of fast RAM.

 

Did people really complain that much about the power supply? I know they would get warm, but it didn't seem like a problem that would doom a computer.

 

Definitely not a scene I ever expected to see on television, though. It would have really been something if they'd included a TI-99/8 prototype on the conference table.

[+mizapf]

 

It sounded like they were referring to the 256 byte "scratchpad" area, which was the only RAM available on the 16 bit bus. The rest was on the 8 bit bus, which meant the TMS9900 couldn't live up to its potential. Although, it seems like *that* was the bottleneck, not the 256 bytes of fast RAM.

 

Interestingly, the problem is not the 8-bit bus but the fact that the processor has a 16-bit bus and byte operations. Almost all write operations to memory imply a previous read operation so that the processor can fill in the unchanged byte. Maybe due to simplicity in the microcoding, the word operations also use read-before-write.

 

I did some research for my lectures to find out how they did it on x86. The 8086 also has a 16 bit data bus and word and byte operations, but Intel solved it much better: They added the LSB of the address bus (A0, but called A15 on the TI) and another line called Bus High Enable (BHE). With these two lines you can control what byte in memory shall be changed. The later processors (386 and later) use one control line per 8 bit of the data bus.

 

Also, the 8088 (the actual IBM PC (XT) processor) only uses an 8 bit data bus like the TMS9995 (Geneve, TI-99/8), including byte multiplexing, which is also done on the TI-99/4A main board.

 

So we have to admit that the TMS9900 architecture was a bad design at that point. Others did better.

[Omega-TI]

 

Did people really complain that much about the power supply? I know they would get warm, but it didn't seem like a problem that would doom a computer.

 

 

Back 'in the day' I remember people complaining about them. In fact there were two different types....

 

The FIRST model which gave of more heat...

 

This SECOND model (which was in the QI console) was also for sale at Rip Shock for a time after TI bailed-out.

[Gary from OPA]

the point is the tms9900 was never to be in the ti99/4 or /4a we just ended up getting luckly.

 

the whole system was to be an 8bit databus with 16bit cpu, with the 256byte 'ram' on the cpu die.

 

but the have silicon die issues, i have one of rare cpu's designed to be in original ti99, its similar to 9995, just a bit weaker, and a little unstable but works 90% of the time, not good enough for production.

 

i wonder if any of 8bit motherboards exist still someplace, it would be neat to see one, there was even one with z80 retro-fitted inplace, before the whole pcboard was redesigned with tms9900, that was very last minute.

 

even gpl itself was an 8bit opcode lang.

 

but in long run i think it worked out with us have a tms9900 in system, alot more people decided to hack and mod and play with ti99 because it it, without it there might not even be ti99 fanbase today, they all be throwed into landfill long time ago and forgoted about.

 

anyhow, back on topic any clip of this show we talking about, or where can i find it?

[Omega-TI]

...any clip of this show we talking about, or where can i find it?

 

No kidding! I want to see it too!

[Willsy]

I have the URL of a torrent site that has episodes 1 to 7. I'm downloading them right now. I imagine it's against forum rules to post link of that nature - therefore, if you want the link, please send me a PM with an email address to send the link to.

[Gary from OPA]

I have the URL of a torrent site that has episodes 1 to 7. I'm downloading them right now. I imagine it's against forum rules to post link of that nature - therefore, if you want the link, please send me a PM with an email address to send the link to.

Which episodes is the ti99 one?