Personal Computer Museum, Canada's Videogame Museum

Texas Instruments TI 99/4A

Texas Instruments TI 99/4A

Speed3 MHz
Memory16 KB

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Texas Instruments

TI 99

Release Date: 1/1/1979
Manufacturer: Texas Instruments
Original Retail Price:
Adjusted Inflation Price:
This very successful computer produced a large number of cartridge games and even had a large expansion system with a disk controller (very uncommon, but shown here). Launched at $700 US, this computer used a TI TMS 9900 microprocessor (the world's first single-chip 16-bit CPU). Many interesting add-ons such as a speech synthesizer were also available. The TI had other cousin machines but the 99 / 4A was by far the most popular. Near the end of its life it was repackaged in a beige casing. This cost reduced version failed to catch on as more powerful computers came onto the market.


This computer is currently interactive in the Museum.

TI Speech Synthesizer Module

TI Speech Synthesizer Module
Release Date: 1/1/1979
In the early 1980s, TI was known as a pioneer in speech synthesis, and a highly popular plug-in speech synthesizer module was available for the TI-99/4 and 4A. Speech synthesizers were offered free with the purchase of a number of cartridges and were used by many TI-written video games (notable titles offered with speech during this promotion were Alpiner and Parsec). The synthesizer used a variant of linear predictive coding and had a small in-built vocabulary. The original intent was to release small cartridges that plugged directly into the synthesizer unit, which would increase the device's built in vocabulary. However, the success of software text-to-speech in the Terminal Emulator II cartridge cancelled that plan. (Most speech synthesizers were still shipped with the intriguing door that opened on the top, although very few had the connector inside. There are no known speech modules in existence for those few units with the connector.) In many games (mostly those produced by TI), the speech synthesizer had relatively realistic voices. As an example, Alpiner's speech included male and female voices and could be quite sarcastic when the player made a bad move.

User Comments
Lloyd Lindsay, CPA, CA on Monday, January 04, 2016
I loved my TI 99/4A. It was a great machine, and I belonged to a TI 99/4A club. I bought a desktop TV for my monitor and justified its cost to my wife by telling her that she could watch her TV programs on it as well. The computer was well ahead of its time in many ways. It used 16 colours, not just a single colour on a black or blue screen. I used a US accounting program that was written in "Extended Basic" and I was able to modify it to accept Canadian postal codes. Of course, I could play games on it too, and my wife did not get to use the TV very much. This wonderful device had only one problem. TI required programs to be inside cartridges that were unique to that computer while other computers could run programs recorded on magnetic tape or floppy disks. Because of this, programmers began selling their programs recorded on the more universal media that other computers could run.
Terry Ritchie on Tuesday, March 10, 2015
Back in 1982 when I was clicking away on my TRS-80 Model III a friend of mine received a TI994/A from his dad. Wow, this computer was cool! He had the expansion box, TI monitor and voice synthesizer. It wasn't long until I was spending more time on his computer than mine! I was amazed by the color, true sprite engine built into it, sound and 16bit processor. It didn't take us long to write our first game, a BattleZone clone. I wish I still had the diskette we saved it on.
Kevan on Monday, August 04, 2014
This was the FIRST computer I ever owned, and it's always had a special place in my heart. As a middle aged man, I'm reliving my youth by getting back into the real thing. I found a group of friendly people online waiting to welcome back current and former users. Drop on by and say hello at this url:
Jim Oblak on Thursday, January 24, 2013
I got one of these when they were being cleared out for $50 in the early 1980s. One can find an emulator somewhere on the internets to run this system on Windows. The one thing I remember from this is "Shift-838", which is apparently a similar memory for others, as indicated in a Google search.
C.B. on Saturday, January 07, 2012
I also had a TI 99/4A in the early 80's. Wrote several programs in Basic to understand fuel pricing at retail facilities? Great to play with. Recently purchased two more for accessories and now have a Speech Synthesizer with Parsac and Alpiner Cartridges. Do I need anything else to program my speech into my TI? Thanks in advance. CB
J on Thursday, March 31, 2011
Was given to me in the early '90s. Spent hours and hours making up programs in BASIC and painstakingly saving them to tape. Favorite accessory was the speech synthesizer, but recently connected everything up and ran an old foul mouthed program I had made. Even curse words are pretty hard to understand unless you already know what you typed. The problem with with this system was that it took a ton of accessories to do anything. Just to use the thing as a simple word processor required a word processor cartridge, a high priced floppy drive, tower (called an "expansion unit"), print controller, and printer. Even then, all you get is ASCII on a thermal roll similar to receipt paper, which turns brown in time. Fun for a child, but the Apple IIc was quite a bit easier to use right off the bat.
Mike on Monday, September 13, 2010
This was the first computer I bought. My kids are now grown but remember the games that were with this. I used the cassette tape backup. Every now & then I see one on E-Bay and must stop myself from bidding on it. I didn't pay $700 for it - more like $150 to $199. No monitor.
James Ferfolia on Monday, February 22, 2010
TI99/4a was my first computer. I still have it packed away too. I had to comment after reading that the little door on the speech synthesizer actually had a purpose. I remember making it "talk" and bite stuff, lol... Thankfully I never broke it. I still say "I'll get you Bigfoot" from time to time... Of course no one I know has ever played the game I'm quoting. Entered quite a few Ti-Basic programs on that computer too. Too young to do anything but copy them out of books at the time but still... I think I might still have the cassette deck I used to save them as well. Good times indeed.
Dan Bergey on Wednesday, February 17, 2010
This was my first computer and I remeber saving up for the extended basic cartridge. This allowed you to create sprits (better graphics). I wish now that i had stayed with programing. I have visited the museum and if you are in Southern Ontario it is well worth the visit! So many great memories.
Tim in PA on Wednesday, February 17, 2010
I remember, at the age of 13, saving my money for one year to buy the TI99/4A at KMart, on sale for around $100 - just the console and nothing else. I fondly recall learning BASIC, and then Extended BASIC. One of the coolest things was the ability to program "sprites", which helped me create a few games for my family and friends. The cartridge games were a source of endless fun too: Parsec being one of my favorites. Thanks to such a positive experience with the TI99/4A, over the years I learned other programming languages on various machines and now run my own computer software company.
Matt Wolfgang on Thursday, March 26, 2009
I have several TI-99/4a's in my garage as we speak. I also have the expansion box and TWO floppy drives. I set it up and played Lode Runner on it just a couple of years ago. I'm amazed that the floppy disks still have the data. I have a ton of software, including 100+ cartridges and Microsoft Multiplan. I actually learned Basic, Extended Basic, and TMS9900 assembly on this PC.
loading via tape drive on Monday, November 24, 2008
This was alos my first computer, even before the VIC-20. We actually loaded programs off a tape recorder, not a tape drive. Had to have the volume up for it to load proberly as the signal was ran from one of the audio jacks to the 99-4/a, it would take a while to load and many times would tkae more than one try. gthe sound is hard to describe, but if you ever loaded programs this way, you wouldn't for get it. loved munchman though, especially withthe cheat codes that let you pick any level
Michael Beaudoin, (cyb3r ph4ntom) on Sunday, September 16, 2007
The TI 99/4A was the first computer I owned. My dad refused to have a computer in his home. Later he relaxed a bit and would allow one but he would not buy it. I managed to save enough money, $107.00 after tax, to buy one for myself. I was so excited, I finally had my own computer. Unfortunately I couldn't afford to buy anything to go with it until much later but, it made for many long nights of tinkering with code. It was a great starter computer. Although I was introduced to computers via the TRS-80, (trash 80), the TI 99/4A was a huge improvement and more enjoyable. Oh the days when you had to write your own code. cyb3r ph4ntom
Sean Smith on Thursday, June 14, 2007
I remember the TI99/4A - the first computer I ever used. My father bought it home one day when I was in grade 6 (1980, I think) and promptly set out to write a program to calculate income tax for it, being an accountant. He managed to fill the RAM in doing so. I remember playing Parsec with the speech synthesizer as a kid too.
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* Inflation data courtesy of Values are approximate using our own calculations.