Re: [CAD_CAM_EDM_DRO] Re: A Z80 guy needs help!

mariss92705 wrote:

>
> What I wrote about rounding errors had an error itself.
>
> > Vx = (D + delta) * sin(theta) - D * sin(theta)
> > Vy = (D + delta) * cos(theta) - D * cos(theta)
> >
> > Again, replace D with D + delta for the next time increment.
>
> That is wrong. It should have been:
>
> Vx = (D + delta D) * sin (theta) - X position
> Vy = (D + delta D) * cos (theta) - Y position

For binary maths and trig, you might want to look up
the 'cordic' method.

The best place to ask is either comp.arch.embedded,
comp.arch.dsp, or a rabbit forum.

> Replace X with X + Vx; (this is now the new X position)
> Replace Y with Y + Vy; (this is now the new Y position)
> Replace D with D + delta D; (this is now the new vector lenght)
>
> "Delta D" is the distance moved along the vector in 1/1,024 sec.
> "Delta D" varies with acceleration.
> "theta" is the angle of the vector, and stays constant.