Input from a computer

Christopher Agocs

I am trying to drive two motors using the SX controller, and a computer will be sending simple commands (move forward, turn left, stop). The best way to do this of which I can think is to have the computer set and clear two pins on the SX. Eventually I'd like continuous control for both motors, but I could probably hack that together on the computer side if needed.

How have people done this in the past? I'm trying to think of ways using the phone jack (EDIT: Or the computer's sound card) and similar on the professional development board.

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Christopher Agocs
Georgia Institute of Technology

Post Edited (Christopher Agocs) : 7/1/2008 8:56:48 PM GMT

Velocit

You could use a MAX232 line driver on the SX side of things and take serial inputs from your computer. This method would only require one I/O pin. Since you only need to control a few commands, you would only need to send one byte per command: i.e. $00 = forward, $01 = reverse, etc.. The computer interface could be as something as simple as HyperTerminal or something as complicated as a custom VB program.

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-Paul

Zoot

You can also construct a simple level shifter with parts you may have on hand. See attached. Also see better shchematic and some sample code in Nuts/Volts 143: www.parallax.com/Portals/0/Downloads/docs/cols/nv/vol8/col/nv143.pdf

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When the going gets weird, the weird turn pro. -- HST

1uffakind.com/robots/povBitMapBuilder.php
1uffakind.com/robots/resistorLadder.php

Christopher Agocs

I suppose I was just being lazy by refusing to consider RS-232. Thank you for the .pdf, Zoot.

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Christopher Agocs
Georgia Institute of Technology