Get timestamp difference in 9hrs format

HI,

I have a requirement where i need to find the timestamp difference and then convert it to 9 hours format. This mean instead of 24hrs a day, i need to consider only 9hrs (working hours only) a day.

I thought of calculating first as 24hours format using Function Module /SDF/CMO_DATETIME_DIFFERENCE (Output for this is number of days and hours), then multiply the result with number 9. Somehow i feel this is not correct as we can get hours result as 17/20/23hrs. when this hours i divide by 9hrs, probably i might get 2 days. which is not correct.

Please help me to resolve this issue. Thank you in advance.

Thansk,

Deepika