Small letters indicates smaller notes ... (r ,g ,m, d....n) = [ri1 , ga2, ma1, da1 ,ni2]
Capital letters indicates higher notes (R , G, M, D N) = [Ri2, Ga3, Ma2, Da2, Ni3]

Please check this video to understand swaras:    • Violin first lesson, How to play Sa  ...  


Regards,
Sreelal