On Tue, 16 Nov 2010 00:51:02 -0500, "Michael A. Terrell"
wrote:


John wrote:

You could use a couple of the outputs and run them through a binary to
decimal converter. Two outputs would change to four outputs, four
outputs would control sixteen outputs.


A binary to decimal converter would change 4 ouputs to 10 outputs.

I don't go BCD, but I use this concept on inputs all the time. A
rorary switch with three inputs has eight detents or positions. A
rotary switch with two inputs has four positions. Or four inputs can
have 16 positions. Useful in operator panels for things like speed,
feed, jog increment, mode etc. saves a lot of inputs.

I'm not seeing this concept on outputs. I'm still going to need one
opto device per out to go from 5 volt TTL to real world 110 VAC or 24
VDC. The optos are the limiting thing, there's lots of computer
resource.

Karl