diff --git a/src/InputOutput/IHMImpl/Params/PlotImpl/IHMInputOutputParamsPlotClass.php b/src/InputOutput/IHMImpl/Params/PlotImpl/IHMInputOutputParamsPlotClass.php
index 3300313..61f06ff 100644
--- a/src/InputOutput/IHMImpl/Params/PlotImpl/IHMInputOutputParamsPlotClass.php
+++ b/src/InputOutput/IHMImpl/Params/PlotImpl/IHMInputOutputParamsPlotClass.php
@@ -717,6 +717,10 @@ class IHMInputOutputParamsPlotClass extends IHMInputOutputParamsAbstractClass
 					$paramNode = $plotNode->getParams()->getParamById($paramInfo['id']);
 					$this->unmarshallInstantSerie($paramData->{'param-drawing-object'}, $plotNode, $paramNode);
 					break;
+				case 'ispectro' :
+					$paramNode = $plotNode->getParams()->getParamById($paramInfo['id']);
+					$this->unmarshallInstantSpectro($paramData->{'param-drawing-object'}, $plotNode, $paramNode, $paramInfo['indexes']);
+					break;	
 				default :
 					throw new Exception('Drawing type not implemented.');
 			}
@@ -991,6 +995,12 @@ class IHMInputOutputParamsPlotClass extends IHMInputOutputParamsAbstractClass
 		$spectroNode = $paramNode->addSpectro($paramDrawingData->{'spectro-yaxis'}, count($indexes) > 0 ? $indexes[0] : NULL, $paramDrawingData->{'spectro-value-min'}, $paramDrawingData->{'spectro-value-max'});
 	}
 	
+	protected function unmarshallInstantSpectro($paramDrawingData, $plotNode, $paramNode, $indexes)
+	{
+	//TBD how to process inexes if they are defined ? 
+		$spectroNode = $paramNode->addInstantSpectro(REQUESTOUTPUTPLOTELEMENTXY_XAXISID, 'y-left', $paramDrawingData->{'ispectro-dimonxaxis'});
+	}
+	
 	protected function unmarshallStatusBar($paramDrawingData, $paramNode, $indexes)
 	{
 		if (count($indexes) == 0)
diff --git a/src/Request/ParamsRequestImpl/Nodes/Requests/RequestOutputPlotParamsNodeClass.php b/src/Request/ParamsRequestImpl/Nodes/Requests/RequestOutputPlotParamsNodeClass.php
index 7b8981c..e3c601e 100644
--- a/src/Request/ParamsRequestImpl/Nodes/Requests/RequestOutputPlotParamsNodeClass.php
+++ b/src/Request/ParamsRequestImpl/Nodes/Requests/RequestOutputPlotParamsNodeClass.php
@@ -25,6 +25,10 @@ define ("REQUESTOUTPUTPLOTSPECTRO_INDEX", "index");
 define ("REQUESTOUTPUTPLOTSPECTRO_MIN", "min");
 define ("REQUESTOUTPUTPLOTSPECTRO_MAX", "max");
 
+define ("REQUESTOUTPUTPLOTINSTANTSPECTRO_NAME", "ispectro");
+define ("REQUESTOUTPUTPLOTINSTANTSPECTRO_XAXIS", "xAxis");
+define ("REQUESTOUTPUTPLOTINSTANTSPECTRO_DIMONXAXIS", "dimOnXAxis");
+
 define ("REQUESTOUTPUTPLOTSTATUSBAR_NAME", "serie");
 define ("REQUESTOUTPUTPLOTSTATUSBAR_INDEX", "index");
 
@@ -109,6 +113,21 @@ class RequestOutputPlotParamNodeClass extends NodeClass
 		$this->addChild($spectroNode);
 		return $spectroNode;
 	}
+	
+	public function addInstantSpectro($xAxis, $yAxis, $dimOnXAxis, $index = NULL, $min = NULL, $max = NULL)
+	{
+		$ispectroNode = new NodeClass(REQUESTOUTPUTPLOTINSTANTSPECTRO_NAME);
+		$ispectroNode->setAttribute(REQUESTOUTPUTPLOTINSTANTSPECTRO_XAXIS, $xAxis);
+		$ispectroNode->setAttribute(REQUESTOUTPUTPLOTSPECTRO_YAXIS, $yAxis);
+		$ispectroNode->setAttribute(REQUESTOUTPUTPLOTINSTANTSPECTRO_DIMONXAXIS, $dimOnXAxis);
+		
+		if (isset($min))
+			$ispectroNode->setAttribute(REQUESTOUTPUTPLOTSPECTRO_MIN, $min);
+		if (isset($max))
+			$ispectroNode->setAttribute(REQUESTOUTPUTPLOTSPECTRO_MAX, $max);
+		$this->addChild($ispectroNode);
+		return $ispectroNode;
+	}
 
 	public function addXSerie($xAxis = "", $index = -1, $min = NULL, $max = NULL)
 	{
--
libgit2 0.21.2