TI-95/TI-74
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TI-95/TI-74
Pictures of these calcs are at http://members.aol.com/hpgene/
Program Language: Basic
System: CPU TI 70c46
CPU Speed approx 270 khz (not mhz)
note: this can probably be overclocked to 1Mhz
What is overclocking? Any cpu speed is regulated by a crystal
(an electronic part which is a specially cut quartz crystal
and two wires attached to it) with a certain speed rating.
If you put in a different speed rating crystal, you can speed
up your cpu. It's as simple as that. You can only go so far
however before some parts of the computer fail because they
are not fast enough for this speed, such as the memory or
other devices. Also note that some functions may be affected,
for example the communication routines to the attached printer
will not work anymore since the printer expects signals at a
certain speed. These crystals are the same ones talked about
by CB radio operators, quartz watches, even "power crystals" from
astrology or whatever you call it.
The ti-74/95 may not use crystals,
but a simpler circuit based on a resistor and a capacitor.
This does the same thing but not as precise timing (which
is usually needed for computers because many of the parts
are carefully synchronized together, and because computers
usually have a clock that keeps time, so you need the more
accurate signal). Btw, you can even overclock a PC, usually
by changing some settings inside the case - on the mainboard.
ROM Built in NA/ Removable 8KB, 32KB
RAM User 8KB (approx) Expandable with 8, 32KB modules
Display 30 Character LCD text display.
Even more info on http://home.inforamp.net/~crown/TI/ti.html
Finally you can buy them at
http://www.hightechsolutions.com/ti7495.htm
The ti-74 is 89 USD.
The LCD can be programmed with full graphics if you know how. I was
told it was the same call char command used on the ti-99.
Btw the basic of the calc is almost the same as the basic of the ti-99
home computer, so if you can find a manual on that it would help. The
ti-99/4 and ti-99/4a were models of an early home computer in the 80's.
It has 16k ram, used the tms9600 cpu (which was a very advanced cpu , 16
bits, running at up to 3mhz) and had a very cool assembly language, you
had unlimited registers cause you could do a context switch and a
special 256 byte area of memory because your registers. It also had i/o
memory in the same concept as pentium does. It had bit manipulation,
hardware multiply, real cool stuff.
Anyhow I've also heard it's possible to program this calculator in
assembly as well and it has a very weird assembly language. Someday I
expect this calculator to join the ranks of the ti-92 on the net with an
assembly shell, bit map graphic games, rom dissasembly, and so on.
Interlink cables are also possible. There is a 10 pin port on the back,
of which some pins form a 4 bit parrallel port.