Re: about clock gating
hey
Clock gating is one way of providing control signal in a sequential system.
For example, if we want a flip flop to work only at certain timing instant then clock going through it can be and gated with a control signal which will go high only in that timing interval.
having said that, clock gating is a bad idea to use (for several reasons like delay introduced by and gate which lead to synchronization problems).There are more elegant ways to provide control signals.For example, in a D-flop and the input signal(the D signal) with the control signal and let clock come to it ungated.
Hope I'm making myself clear.Please Refer to a text on Digital Design for more details.
Regards
tronix