View Full Version : Interfacing a Texas Instrument Calculator with the BASIC Stamp

01-16-2007, 08:40 AM
I'd like any help possible in·a project in which a Texas Instrument 83 plus calculator communicates with a BASIC stamp and then that, in turn, operates a plotter.·

Here's why I think it would be useful and interesting:
1.· The plotter is a real-world mechanical·device, and so when you are able to control it with electronics, that has a certain charm.

2.· The calculator has a built in LCD, and so the programmer has a ready made interface.

3.· The calculator is reasonably rugged, and compact.

4.· If I can get the calculator to control on and off ports on the stamp, then any device out there currently controlled by the BASIC stamp could in turn be controlled by the calculator

5.· The calculator has many built in complicated math functions, and so the calculator could drive equipment which requires these functions.

6.· The calculator is reasonably cheap: @ $90 USD.· Staples office store was even giving them away (rebate of course) when you bought 100$ of back-to-school supplies.

7.· With the calculator as the programmer, you would free up the need for a desktop or a laptop once the stamp is programmed.· This would be useful for remote locations or when you just want the portability and cost-effectiveness of the calculator to download data.

So, I'd like to ask the members of the page here, whether you might be able to point me in the right direction, or even (cough, cough) write some code that would work.

A few notes:·
The website ticalc.org has some projects in which a PIC functions as the interface. The actual protocol that TI uses is proprietary, but people have already broken it down· (see website under "TI LINK PORT"· http://www.ticalc.org/hardware/cables/parallel.html Apparently, the protocol used is I2C, which allows many different devices to communicate to one-another over just two wires.

I have made an earnest attempt to implement the LINK PORT protocol using the circuit drawing attached.· I also tried to implement the I2C protocol using BASIC.· The PIC schematic is attached.·

Anyway, I hope someone out there can help.· I'd appreciate any help.