Add deactivated PT1000 measurement as error flag, startcode for calibration routine

stm-firmware/Makefile

@@ -10,7 +10,7 @@ INCLUDEPATH = -Icmsis -Iinclude
 OBJDIR = obj
 target	= reflow-controller
 LIBRARYPATH = -L. -Lmathlib
-LIBRARIES = -larm_cortexM4lf_math
+LIBRARIES = -larm_cortexM4lf_math -lm
 
 DEFINES = -DSTM32F407xx -DSTM32F4XX -DARM_MATH_CM4 -DHSE_VALUE=8000000UL
 mapfile = memory-mapping
@@ -41,6 +41,8 @@ CFILES += digio.c
 
 CFILES += stm-periph/unique-id.c
 
+CFILES += calibration.c
+
 DEFINES += -DDEBUGBUILD
 #TODO