update the README

Author: wenqiang-gu

README.md

@@ -1,2 +1,19 @@
 # adc-nonlinearity
 waveform processing and fitter for the ADC nonlinearity calibration in protoDUNE-SP
+
+1a) ADC bench test rawdata --> (save2ROOT.py) --> ROOT format
+1b) (AdcSimulation.cc) --> ROOT format
+
+2) commonFormat.cc (if necesary)
+
+3) Saturation identifier.cc & tagger.cc
+
+4) Pedestal subtractor.cc --> simplified waveform in ROOT format
+
+5) eigenFitter.cc --> effective NL correction & response
+
+6) NLReverser.C: convert the best-fit NL correction to an ideal-to-measurement map
+
+7) predictor.C --> given an input charge, predict signal waveform
+
+8) comparison.C: only for comparison