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From: sbailey@sensemedia.net
Subject: Re: PC to control servos
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Len wrote:

>how much current does the control input on a typical servo draw?  Is it >a straight TTL type input?

I haven't measured the current draw on the control line but it is 
probably equal to one TTL load or less.  Remember RC stuff is all battery 
driven and unnecessary logic current load has likely been reduced to a 
minimum to conserve battery life.  Clearly a single line on the parallel 
port can drive it and twenty others like it with no difficulty.

If you are worried about blowing up the parallel port consider isolating 
it with an opto-isolator, but I wouldn't worry too much.

Stew Bailey (sbailey@sensemedia.net) or (sbailey@novell.com)


