Click the green flag to start. Enter a value (up to sixteen minutes) as a decimal (eg 2mins 30 seconds is entered as 2.5) Press enter and the timer will start. Audible alert when the time is up, as well as display of the error in timing.
A remix of my own timer https://scratch.mit.edu/projects/81102970/ using code snippets from @rowanswitzer https://scratch.mit.edu/projects/77352678/ Cup and saucer from http://cliparts.co/cliparts/8TA/Ena/8TAEnaMdc.png