PCW wrote: Also you might try a longer step length (parallel port step lengths are often a few usec longer than programmed due to access time issues)
A parallel port step will either be one whole base thread cycle (if reset is not used), typically 20uS or the length of time that the base thread takes to execute (variable) if reset is used. Or pretty-much as-programmed if reset is used and the step length is set longer than the base thread execution time.
But, the point is, parallel port step time can only really be measured with a 'scope (and not Halscope) but will only be
at least as long as programmed.
