10 Nov
1998
10 Nov
'98
8:56 a.m.
At 00:46 10/11/98 -0500, Ethan Dicks <erd(a)infinet.com> wrote:
Yes, it is. After pulling a part number out of my... after misremembering
the number aove, I checked the schematics. It is the 74922.
> > The problem with replicating the
SuperElf is the keyboard. I have no
> > idea where to get that chip from (74941?), nor an inexpensive source
> > for that many pushbuttons (including some latching ones).
As far as the keyboard encoder chip goes, you wouldn't be thinking of the
74922 would you? It's a 16 key keyboard encoder chip designed, as I
remember, to encode a 4 x 4 key matrix... Anyway, according to the Australian edition of the
Farnell catalogue, both
these chips are still available...
I was surprised to find the number of articles on the web that advocated the
74922 with a Basic Stamp or PIC. My tentative research turned up a price of
$10 or less in the States.
...PCB mount NO push buttons (I think they're
called D6 type)
I would need to see a footprint to know if they fit the existing layout.
Depending on the price, I'd probably be interested
in one of these little
machines too.
I'll put you down, too.
-ethan