On Mar 9, 2:47*pm, Tim Wescott wrote:
On 03/09/2011 09:50 AM, Wild_Bill wrote:

Maybe not what the OP is interested in, but here's a program that is
stated to work with (I haven't tried it) old computer parallel printer
ports.. 486 PC 100Mhz.

Quadrature 5V signals from linear or rotary encoders.

http://www.lindsayengraving.com/othe...rests/dro.html

It'll be DOS only, from the description and the look of the screen
shots. *Windows or Linux machines would need a special driver. *And
you'd have issues with making sure that the program looks at the port
often enough -- if it misses a count, then it'll be off until the next
time you home the axis.

Tim Wescott

I've used the parallel port for I/O quite a bit. Windows plays with
the control bits so I ran DOS7 from a Win98 boot floppy. Writes are
timed to about 1uS in hardware regardless of the speed of the
machine.

jsw