Which PLC?
Some examples from Omron [CJ1M, CP1H and CP1L] and from Idec [ MicroSmart] Series.
These have high speed pulse outputs that are capable of generating relatively simple motion profiles suitable for connecting to Stepper or Servo drives that accept [typically] pulse and direction inputs.
Don't expect tremendously sophisticated motion control using these units, however they do offer a low cost option for straightforward applications that do not involve multi-axis coordinated control.