i have a disk rotating at variable speed(max rpm 600) . i want to know how much time it takes to rotate by 120 degree in each revolution .i have the following equipment with me .Arduino leonardo, 5 volt proximity sensor.i want arduino to do following task.measure the time for each 120 rotation (in millisecond) and record the measured time for each 120 rotation because this time will be varying as disk rotate at variable speed. pls open attached ppt for more clearificationSee More

i just bought a arduino leonardo,i just tried to run hello word sketch on it but i was not able to see any thing on the lcd. all connection was done properly .pin used on arduino- 12,11,5,4,3,2lcd- winstarpls help if anyone has any idea.See More