PS:

>I wonder, how does the original digital odometer cope with the noise? True
>I could lower the pull up resistance and probably solve the problem this w=
ay
>(as long as current draw doesn't become excessive, but as it is normally
>open, and the pulse is short, it's unlikely to be a problem) but it puzzle=
s
>me that measuring the original digital odometer current I get such a low
>value. Is it really that low, or may I suspect something clever is in plac=
e?
>(e.g. it does draw larger currents but only for a very short time?).

I measured the thing.. 400 uA peak, BUT much less (~9 uA) sustained, looks
like I was right in my assumption, i.e. it provides a "high" current but th=
en
the current lowers.

A resistor + capacitor in place?

Moreover, I thought I should also use a lower value cap FIRST in parallel t=
o
filter the high frequency noise coming from the environment. I will try wit=
h
10 nF first, and then change value until (with the wheel not running) I get
no noise anymore. Then I will go back to the "source current" issue, althou=
gh
400 uA could be sourced continuously IMHO, as the reed is normally open.

I'd still like to hear about Your comments though!

Cheers,
Mario

--=20
http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist
.