22 Feb
2000
22 Feb
'00
7:46 a.m.
Tell the group what you're trying to do, based on
your
requirements there are several alternatives!
What type of application is this for?
This is totally off topic, by the way. Sorry...
I have an embedded computer which has four user
readable DIP switches on it. Board is running
at 3.3 volts. I want to be able to distinguish
between 7 possible SPST switches being closed
(one at a time) or all being open. I thought
"OK. I'll just convert the single switch event
to a binary number by hooking it to the appropriate
pins on the DIP switch. Then I'll prevent the
multi-bit numbers from cross feeding the single
bit events by putting diodes in." But, the diodes
have too much resistance for the board to see the
switch as closed. The single-bit switches, 1, 2
and 4, read just fine.
Bill