Speedometer not working

Today i was driving and my speedometer was working fine , then i looked down and all of a sudden it droped to zero. All the other gauges and lights in the cluster are working fine. Any ideas on what the problem could be? Thanks for the help

Is the odometer working?

Im not sure, I wasn't paying much attention to that I think the cable popped out of the tranny im gonna check it tomarrow when i can see.