In June of 1981 Texas Instruments released the TI99/4A model. The "A" comes from the new, improved
Video Display Processor, the TMS9918A. This model also had a much improved keyboard. The release price for
this model was $525, without a monitor. The modulator finally passed FTC requirements, and you could now hook the computer
to the family TV.
As I mentioned above one of the improvements the TI-99/4A had over the TI-99/4 was a greatly improved keyboard. Along
with the improved video chip the TI-99/4A now had upper and lower case characters which the TI-99/4 did not. The new
keyboard also "felt" much more like a "real" computer keyboard.
In January of 1982 TI introduces the Peripheral Expansion Box (known to users as the PEB) which allowed the ability
to easily expand the 99 series. The PEB sold for $250.00 and different cards, RS232, 32K memory etc. could be purchased
in the $200.00 to $300.00 range. Many 3rd party companies later produced their own expansion cards. These varied from
32K cards, to RAMdisks, floppy and hard-drive controllers and the very useful gram cards.
To view some of the expansion cards available for the PEB go
Pictured above is a TI-99/4A, a TI PEB, a TI 10" monitor, and the "way ahead of it's time" Speech Synthesizer.
Pictured above is the "standard" motherboard used in the TI-99/4A series. The heart of this system was the 16-bit
TMS9900 series microprocessor. Also onboard was 16K of RAM.
For more information on the chips on this board go here.
For a larger view of the motherboard and power supply go here.
Click here to see fullsize ad.