SQL & PL/SQL

Hi,

I am using Oracle Database version 11.2.1. I would like to calculate the number of working minutes between two dates where the working hours are Monday - Thursday 8.45am to 17:00pm & Fridays 8:45am to 16:30pm

I found the following function useful in a similar post but wanted some help incorporating the above working days and hours into account

CREATE OR REPLACE
  FUNCTION get_bus_minutes_between(
                                   p_start_date DATE,
                                   p_end_date DATE
                                  )
    RETURN NUMBER
    IS
        v_return NUMBER;
    BEGIN
        with t as (
                   select  case level
                             when 1 then greatest(p_start_date,trunc(p_start_date) + 9 / 24)
                             else trunc(p_start_date) + level - 15 / 24
                           end start_dt,
                           case connect_by_isleaf
                             when 1 then least(p_end_date,trunc(p_end_date) + 18 / 24)
                             else trunc(p_start_date) + level - 8 / 24
                           end end_dt
                     from  dual
                     connect by level <= trunc(p_end_date) - trunc(p_start_date) + 1
                  )
        select  sum(greatest(end_dt - start_dt,0)) * 24 * 60 work_minutes
          into  v_return
          from  t
          where trunc(start_dt) - trunc(start_dt,'iw') < 5; -- exclude weekends
        RETURN v_return;
END;
/

Can anyone help?