Hello. I am looking for assistance with the following issue.

I would like to create a stopwatch that can be started with a button and time is displayed counting up. Then a time can be entered into a cell independently of the stopwatch. Upon hitting another button, such as "Enter time", the stopwatch becomes a countdown timer starting at the entered time value minus the elapsed time. Ideally, I would like to create 5 timers that could be running simultaneously with different values. The stopwatches would also need to have stop and reset buttons.

ex.
Hit "Start Time 1", stopwatch 1 starts counting up.
Enter 0:03:00 in D4 (0:00:45 has elapsed)
Hit "Enter Time 1", 00:03:00-elapsed time is calculated & 00:02:15 is displayed and timer begins to countdown from 00:02:15 to 00:00:00

Appreciate any help.