> use a 12C508, it's cheaper than a 555 and all the caps
    > and resisters that go with it.

    Really? I never thought of it like that.

Well, no, not really.  In unit quantitites a 555 is about $0.50, resistors
(2 required) are about $0.02, and caps are maybe $0.10, for a total cost of
less than $1.  While a 12c508 might be less than $1 in quantity, it's more
than that if you only buy one, and you probably should still have at least
a bypass cap.

However, when you start talking about a 555 connected to a divider chip,
and count in circuit complexity and PC board space and such, I think the
12c508 starts to pull ahead pretty quickly.  A lot of the "neat things"
people have done with 12c508s are replacements for 555-like timers - see
microchip's web page...

BillW