How to enter decimal timer values to plc through hmi

I need to add a timer value of 1.2sec to FX series Mitsubshi series plc through HMI.How can I add a decimal value through a pfoface HMI and how the convertion can be done in the program since 10,100 and 1 msec timers are availiable in plc

Enter a Float value on the HMI, then multiply the HMI value by the correct value and move the value into the timer set value.

Example:
Your timer has a 1msec time base. So 1000 = 1 second.
HMI Input is 1.5 seconds
Multiply by 1000, you get 1500.

I don't know the correct syntax to move the result into the timer's preset value on an Mitsubishi FX PLC.