diff --git a/macros_W/halfVoltPositions680.cxx b/macros_W/halfVoltPositions680.cxx
new file mode 100644
index 0000000000000000000000000000000000000000..79a9f5f63dd858fff18cab5d1805f7be077e463e
--- /dev/null
+++ b/macros_W/halfVoltPositions680.cxx
@@ -0,0 +1,119 @@
+#include <iostream>
+#include <vector>       // std::vector
+#include <algorithm>
+
+using namespace std;
+
+void halfVoltPositions680()
+{
+
+	TString inFile = "objects/histHalfVolts680.root";
+
+	TString outPeaksFile = "parameters/halfVoltPositions680.par";
+
+	TFile *fr = new TFile(inFile.Data());
+	if (fr->IsZombie()) {
+		Error("halfVoltPositions680.cxx", "File %s was not open correctly.", inFile.Data());
+		return;
+	}
+
+	TH1D *hch[64];
+	TGraph *gr[64];
+	TString hName;
+
+	for (Int_t i = 0; i <64; i++) {
+		hName.Form("ch%d", i);
+		hch[i] = (TH1D*)fr->Get(hName.Data());
+	}
+
+
+
+	TString cName;
+	TString cTitle;
+
+	TCanvas *cWork[11];
+	for (Int_t i = 0; i < 11; i++) {
+		cWork[i] = new TCanvas();
+		cName.Form("can%d", i);
+		cTitle.Form("canvas %d", i);
+		cWork[i]->SetName(cName.Data());
+		cWork[i]->SetTitle(cTitle.Data());
+		cWork[i]->Divide(2, 3);
+		cWork[i]->cd(1);
+	}
+
+	ofstream calFile;
+	calFile.open(outPeaksFile.Data());
+	if (calFile.is_open()) {
+		Info("calPeaksVoltage.cxx", "Positions of 0.5V peak will be saved in %s.", outPeaksFile.Data());
+	} else {
+		Error("calPeaksVoltage.cxx", "File %s was not open.", outPeaksFile.Data());
+		return;
+	}
+
+	Double_t x, y;
+
+	for (Int_t i = 0; i < 64; i++) {
+		Int_t cNumber = i/6;
+		cWork[cNumber]->cd(i-6*cNumber+1);
+		hch[i]->Draw();
+		if (i!=42 && i!=21 && i!=11 && i!=41) gr[i] = searchPeaks(hch[i]);
+		if (i == 11) {
+			gr[i] = searchPeaks(hch[i], 0.2);
+		}
+		if (i == 21) {
+			gr[i] = searchPeaks(hch[i], 0.08);
+		}
+		if (i == 41) {
+			gr[i] = searchPeaks(hch[i], 0.08);
+		}
+		if (i == 42) {
+			gr[i] = searchPeaks(hch[i], 0.08);
+		}
+		//take a peak corresponding to 0.5 V for 680 pF
+		gr[i]->GetPoint(1, x, y);
+		calFile << i << "\t" << x << endl;
+	}
+
+	calFile.close();
+
+	return;
+}
+
+TGraph* searchPeaks(TH1D *hInput, Double_t relHight = 0.05) {
+
+	Double_t voltage[] = {0.5, 1., 1.5, 1.75, 2., 2.25, 2.5, 2.75, 3., 3.25, 0.};
+//	const Double_t corr1e = 1.18;
+//	const Double_t corr1e = 1.;
+
+	hInput->GetXaxis()->SetRangeUser(150., 1000.);
+
+	hInput->ShowPeaks(6., "", relHight);
+
+	TList *functions = hInput->GetListOfFunctions();
+	TPolyMarker *pm = (TPolyMarker*)functions->FindObject("TPolyMarker");
+
+	const Int_t noPeaks = pm->GetN();
+	Double_t *energy = pm->GetX();
+	std::vector<Double_t> vEnergy;
+
+	for (Int_t i = 0; i < pm->GetN(); i++) {
+		vEnergy.push_back(energy[i]);
+	}
+
+	std::sort(vEnergy.begin(), vEnergy.end());
+
+	TGraph *gr = new TGraph(noPeaks+1);
+	const Double_t delta_vEnergy = 2*vEnergy[0] - vEnergy[1];
+
+	vEnergy.push_back(delta_vEnergy);
+	gr->SetPoint(0, vEnergy[10], voltage[10]/voltage[0]*(vEnergy[0]-delta_vEnergy));
+	if (noPeaks == 2) Info("searchPeaks", "%d peaks found in hist %s", noPeaks, hInput->GetName());
+	else Error("searchPeaks", "%d peaks found in hist %s", noPeaks, hInput->GetName());
+	for (Int_t i = 0; i < noPeaks; i++) {
+		if (i>=10) break;
+		gr->SetPoint(i+1, vEnergy[i], voltage[i]/voltage[0]*(vEnergy[0]-delta_vEnergy));
+	}
+
+	return gr;
+}