[comp.os.msdos.programmer] delay of partial milisecs

roder@plains.NoDak.edu (Mark Roder) (10/17/90)

	I am trying to use my parallel port to drive a servo for a robotics
project.  The servo has a control line that reads a pulse to find out where
it is supposed to be.  A 1 milisec pulse is the left side, a 1.5 milisec is
the middle,  a 2 milisec is all the way to the right, and any other
value is in between (1.25 milisecs is 1/2 way between left and center).

	I am using TC++ as my programming language.  My original plan was
this: do a outport() to turn the line on.  And then after the required
delay, do a outport() to turn the line off.  The problem is that the delay
provided only does whole milisecs. Is there a way to get to the desired
partial milisecs? 

	Is there a way to increase the interrupts from the clock ticks.
These occur 18.2 times a sec(something like that).  Can these be increased
to be accurate for the control of the servo? 

	Is there a countdown timer that I can use to cause an interrupt
after it counts down from the required time?

	I would appreciate any help.  I need to get this servo to work so
that my project is a project and not a pile o parts.  Info: I am using a 20
mhz 386 sx running dos 4.01.  I need to have at least 20-30 steps in the
servo from all the way left to all the way right.  I would like to keep the
project to as little supporting hardware as possible(i.e. cheap)

Thanks.  Please e-mail me, I don't have the luxury to do my long rn
sessions any more.

Roder.

roder@plains.nodak.edu