aggeregate 3hourly precipitation to daily and back to 3 hourly

Dear Uwe and others,

for a specific hydrological model, I need a 3 hourly equally distributed precipitation data, e.g., 64 mm daily rainfall will be 8 mm/3hr. what I have a normal 3hourly precipitation data which is not equal at the 3-hour time scale. is there any way to do this in CDO.

Thanks for your support