Pulse oximeter

NIKET AGRAWAL said:

TI had provided an application note "slaa274" in which they have not used a DSP

You mean this:

Application Report SLAA274B–November 2005–Revised February 2012

A Single-Chip Pulsoximeter Design Using the MSP430

here: http://www.ti.com/general/docs/lit/getliterature.tsp?baseLiteratureNumber=SLAA274

 but I didn't get how the things will be done without a DSP.

Isn't that what the report is all about?!

The document contains a link to the Olimex page - which includes the software!