Hi,
I have to convert 4 - 20mA from sensor to 1 to 5v using a resistor.
Extract value using ADC and save data in modbus registers. Request someone to please help me with the best schematic and the controller which goes well with this.Thanks in advance.

 

Drop a 250 ohm resistor into the current loop, that gives you the 1V to 5V output.

I use PIC controllers most of the time, just about any core that works off 5V will do for this, just make sure the 5V is well regulated as you need to use it as the ADC reference too.