title: Millisecond precise python timer
body: <p>I work on a python script designed to control multiple actuator at the same time. To simplify, let's say I need to control 2 electric motors.</p>
  
  <p>With the multiprocessing module I create a process for each motors, and a process to save the data on a sheet.</p>
  
  <p>This part of the script works fine, however I need to command my motors at precise times, every milliseconds, and the time.time() or the time.clock() functions seems to be unreliable (triggs between 0.05 and 30 millisecond!)</p>
  
  <p>Is it "normal" for these functions to be so erratic, or is this caused by another part of my script?</p>
  
  <p>EDIT: I used the datetime function (see below) to improve the precision, but I still have several discrete level of error. For example, if I want 1ms, I get also 1.25, 0.75,1.5...
  So IMO this is due to computer hardware(as Serge Ballesta said).</p>