gEDA-user: furnace controller II: I/O driver

[DJ Delorie <dj@xxxxxxxxxxx>]

I've talked about this before, and this is probably the weirdest part
of the new furnace controller, so I'm open for input.

The furnace controller will have eight of these I/O drivers, two per
zone.  Nominally one for input and one for output, but in my case it's
one for the dallas 1wire interface and one 9600 baud for the LCD
panels.  I'm trying to stay a bit generic to make the board useful for
other applications, or future changes to the thermostats.

The goal is to, essentially, create a high current filtered tri-state
I/O port, using two GPIO pins.  Details on the web page:

http://www.delorie.com/house/furnace/pcb2/io_port.html

If Maxim has a chip for this, let me know ;-)