There is an important phenomenon which anyone dealing with CNC machines and numerical control should be knowing and that is the method by which the numerical codes such as the G-code and M-code works in actual practise. This is important because the knowledge of the underlying process would help a person to appreciate the importance of the same and to handle any discrepancies that might arise during the manufacture process using numerical control on CNC machines. This is important because inappropriate or inefficient use of M-code can lead to deterioration of the execution time of a program.
To take a simple example let us support that the code M03 is executed on a CNC machine. This particular code turns the spindle on in a forward direction. Hence a signal is given to the spindle motor in order to execute the command. But what do you think happens after that?
Well it might be anybody's guess you might say and the next step or code would be executed but you are wrong here if you think that way. The controller waits to see whether the spindle actually reaches the speed at which it is meant to operate before actually going on towards the next step.
This is obviously important since any lapse in such a feedback could ruin the manufacturing process.