Code runs on the stellaris launchpad.

Uses Energia.

Wheatstone bridge circuit: http://iitg.vlab.co.in/?sub=61&brch=174&sim=1035&cnt=1 (can't be used as such ... I think it just gives the idea)

NI app note; explains how to use 3-wire pt100 in bridge form: https://newton.ex.ac.uk/teaching/CDHW/Sensors/an046.pdf

Microchip app note: http://ww1.microchip.com/downloads/en/appnotes/00687c.pdf (precision temp sensing with rtd)

avrfreaks discussion: http://www.avrfreaks.net/forum/pt100-conditioning-circuit

Purpose of 3 wires in a pt100: https://www.vertex-qis.co.uk/Manuals/PT100_con.pdf

RTD measurement theory: http://www.omega.com/techref/rtd-measurement-and-theory.html

A post which mentions a simple idea: https://forum.allaboutcircuits.com/threads/need-help-with-pt100.36279/