gps and sbas

does anyone know if a gps rec. that also uses waas does the correction in the gps unit itself of do you have to do the correction your self in your code?

thanks
harry

i found the answer if your rec. receives the DGPS signal from 1 of 4 sats in america it will do the DGPS cal. its self u-blux is one that will with and acc. of 1m