I have searched alot about industrial servo motors and their application but the problem is about the pulse command used in position control mode, can I use a 555 timer for the generation of such pulses? Secondly what are the variables affected by the pulse width? Lastly what is the relation between number of pulses and the step angles of the servo motor shaft? I'm using the ASDA-A2 servo drive with 20-bit encoder resolution. http://www.delta.com.tw/product/em/download/download_main.asp?act=3&pid=2&cid=1&tpid=1 for manual
1) You can, since the 555 has an open-collector output.
2) As long as the pulse width is wide enough (~5 usec for single-ended inputs driven by open-collector NPN) pulse width is completely irrelevant.
3) One step will produce a 1-bit change in the encoder output. Since you're using a 20-bit encoder, one step will produce an angle change of 360 / (2 ^ 20), or about .00034 degrees.