Re: TI-H: Keyboard
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Re: TI-H: Keyboard
I use the PIC microcontrollers from Microchip (http://www.microchip.com/ ), some
people use the AVR line from ATMEL (http://www.atmel.com/ ).
PIC and ATMEL chips can be purchased from http://www.digikey.com/ and other
electronic suppliers. The programmers needed can be built out of spare parts,
or from parts from Radio shack or any other small electronics store, usualy for
less than $10.
The assemblers are free, Microchip has a free IDE for their assembler called
MPLAB, and I believe that Atmel has an equivilant for their chips. You can also
program then in C, there are many C compilers for both chips, most of which have
a demo or free version which only limits code size (I use CC5X, from
http://www.bknd.com/ , the free version compiles all the programs I've needed so
far).
You can get started in PIC uControllers for under $20, including one flash chip
(16f84).
More information and links to PIC resources, including cheap programmers and
sample programs, can be found on my site:
http://www.ubasics.com/adam/pic/
I hope this helps!
-Adam
Owen Anderson wrote:
>
> I would be interested in this product. I'm not in need of advising, except
> in getting my hands on the microcontroller. I believe I can get the rest.
> Would I be charged for asking you how I can get such a microcontroller?
>
> Owen Anderson
> resistor@mac.com
>
> on 8/31/00 12:17 PM, M. Adam Davis at adavis@ubasics.com wrote:
>
> >
> > Well, here's the deal. You have two routes to go:
> >
> > One:
> > The TI-89 and 92 have external control ability, ie, you can send keypresses to
> > the calc, and it will handle them just as if they were typed from the keypad
> > without any programming whatsoever. Spiffy, huh? This requires an external
> > keyboard interface involving a microcontroller.
> >
> > Two:
> > The hardware interface for the graphlink port and the AT type keyboard (ps/2)
> > are similar, both are open collector outputs/inputs. Therefore it is possible
> > to make a cable which hooks the keyboard directly to the graphlink. The issue
> > here is that they do not speak the same protocol, and the keyboard does not
> > spit
> > out ascii characters. You will need to write a program on the calculator
> > which
> > will directly control the pins for the graphlink, accept input, run it through
> > a
> > translation table, and then insert it into the key buffer on calc.
> >
> > I personally would go for the first routine, as I am more comfortable dealing
> > with uControllers than I am with programming the calc. I am certian, however,
> > that an enterprising DOORS developer could go with number two just as easily
> > as
> > I woul go with number one.
> >
> > For information on interfacing to a keyboard (electrical and protocol) see
> > http://www.beyondlogic.org/
> > For information on interfacing and programming the TI calculator, see
> > http://www.ticalc.org/
> >
> > I do a small amount of consulting. If you want me do do the work for you for
> > option one, I would charge $45/hr labor. I have the materials, and would
> > estimate about 5 hours from spec to design to test to completion. This would
> > include one finished product, embedded into a cable.
> >
> > One item worth mentioning: Keyboard manufacturers have never needed to worry
> > about keeping a low power consumption. Some keyboards suck 250mA or more,
> > using
> > a complete set of four AA's in under 6 hours (continuous use). You are
> > advised
> > to explore this and other items before embarking on this project.
> >
> > -Adam
> >
> > Nivek wrote:
> >>
> >> --- Grant Stockly <gussie@stockly.com> wrote:
> >>>
> >>>> hey, what has happend, is this compleat??? can i get one??? where???
> >>>> thanks.
> >>>
> >>> Nothing has happened. No it isn't complete. You can't get one. No
> >>> where.
> >>>
> >>
> >> darn, can anybody give me info on how to write the program and what
> >> kind of converting i would need to do, so that i can do it myself. for
> >> TI-89 if possible.
> >>
> >> =====
> >> Nivek
> >> Nivek_ent@yahoo.com
> >> http://come.to/NivekEnterprises
> >>
> >> __________________________________________________
> >> Do You Yahoo!?
> >> Yahoo! Mail - Free email you can access from anywhere!
> >> http://mail.yahoo.com/
> >
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