how to generate time series data?

I calculated vector D(48*1) values for one day 30 min interval in .m file program. Now I want to use this D vector into simulink model with 1 sec time stamp for a day.(fix first value for 30*60 seconds and next 30min time stamp value will be fix for that duration for 1 sec time stamp). So how to read in simulink this data in timeseries format with 1 sec interval for one day because in simulink 'from workspace' works when its first column is time values and second column data values.