Lisp program for Autocad

Hi,

I need help creating a custom lisp for making segmented lines in Autocad.
Function overview:
Pick two points.
Ask for gap distance.
Ask for desired line segment length.
Calculate and round off number of segments.
Show calculated number of segments, accept or enter new number.
Draw calculated (or chosen) nuber of lines between points, starting and stopping with gap distance and separated with gap distance.