Re: 5-phase steppers

[Jon Elson <elson-at-pico-systems.com>]

Paul wrote:

>Hi Peter
>
>EMC has several stepping modes - Step/Dir, Quadrature, and Four Phase. It 
>wouldn't be too difficult to modify the last type to generate the five phase 
>sequence. Then all you'd need would be the switching stages.
>  
>
The problem with this is it would take more than 2 bits/axis, so a single
parallel port would only be good for 2 axes (unless you use a control bit,
too, for the 3rd axis).  That might not be so bad, of course.  But, you 
could
also build a very simple bidirectional counter to generate the 5 phases, and
feed this with the usual step/dir signals.  This would also make bench
testing a lot simpler.
I don't actually know what the drive sequence for the 5-phase steppers is,
they generally connect the windings up to make a pentagonal ring, with
5 wires coming out of the motor.

Jon