I trying to figure out how to create a macro for a countdown chronometer, i need to be able to set the countdown value on sheet1 B1, need to be able to add a start, stop and reset button. What i need the macro to do is will allow me to set countdown on B1 to any value, stop the countdown at any moment, re start were it was stop, ten seconds before reach cero to turn button red and when reach cero to stop, when click reset button need it to set the same countdown value was before.

Any suggestion is greatly appreciated... thanks in advance for any help!