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Unread 28-01-2007, 20:08
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Re: Digital to OI Analog

Quote:
Originally Posted by Stuart View Post
no Im talking about my solution(hack) with the pic and a digi pot only(no voltage devider, or fancy things like that)
this is all in the context of the original question of how to split a analog channel in to more than 1 digital channels
Hello Stuart,

What you are doing, and what Mike has done on the Chicklet, are essentially the same except that he's encouraging you to add one resistor (per channel) so that you don't throw away 10% of your pot's resolution. If you make your series resistor a trim pot, or hand select the resistor, you can remove the error introduced due to the absolute value of a given digital pot.


The origional poster, Marcan, was interested in the "how-to" aspect of interfacing to the OI, and I think someone else had brought up multiplexing.

Marcan was also talking about pulling power from the joystick connector, and I'm not sure anyone had addressed how to calculate the error that will result from doing so... so I elected to explore that topic in a way that hopefully would provide some insight as to how to make a personal decision on how much is too much, and what the tradeoff's are.

From my own exploration of this interface, I found some things that disagree with what IFI has documented, and those were included in my posting, and have also been brought to the attention of IFI in case they want to correct, or clarify, those portions of their user manual.

Thanks,
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--Dave