Grossel , no i didn't measured stepmotor terminals by a scope bcoz i dont have a scope. and yes i am trying to say the same thing that "there is something wrong with my OSCillator ( pin 16 on L297), but i dont know which resistor and capacitor to use in osc to get more speed. And what EXACTLY happens is = when i run the motor at 150 rpm( 150rpm *200 stes rev. / 60 seconds = 500 Hz) the motor runes very well (with good torque), But when i try to run the motor at more then 160 rpm (from any computer software emc2, mach3, kcam) it just stats vibrating ( the driver is giving power to the motor but the motor is not able to run that much fast, so it is just vibrating ).
Shortbus, i am using a computer's parallel port for l297's pin 18, and yes my motor is 200 step/revolution.
so, guyz if you know that hoy to change the OSC pins Hz then plz let me know about it, And is that true that with more Hz the motor will run fast?
AND yes yes, i just forgot to tell you that = the motor is runing at 150 rpm in both half and full step mode. if i try to go at 160-1000 rpm in both modes then i face the same problem . so i thing that there is surely some problem with the OSC on L297.