After diploma in engineering you may join lateral B.Tech course and can directly enter into the second year. If you want to work alongside then you may join correspondence course. 
List of lateral entry colleges (correspondence) : 
-JNTU-SCDE 
-Acharya Nagarjuna University 
-IGNOU 
To take admission you may directly contact the university officials as lateral entry norms differ from one university to another. 
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