Re: TI-H: Add LEDs to your link cable!
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Re: TI-H: Add LEDs to your link cable!
>> > Actually, I believe an LED uses too much current or doesn't switch quickly
>> > enough, for when I tried that the link simply failed to function. (Unless
>> > I really did something strange... :) )
>
>I don't know what you could have done, unless you connected the LEDs
>wrong, meaning in series, or you used a resistor with too low of a
>resistance.
The linkport can only give out maximum ~0.3 milliamps before it will
be pulled to ground and produce an error condition. Even the
lowest-power LEDs I've seen require 0.8 milliamps. What's happening
is that your parallel port is trying to source all the current, and if
it can't it will end up biasing the wires so that it won't work
anymore.
And it definitely won't work with just the TI-TI cable, no way, not
unless you add an external power source for the LED.
-Mel
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-The TI-Memory Expansion Homepage
-http://www.egr.msu.edu/~tsaimelv/expander.htm
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