ngscopeclient · Nov 29, 2020 · Nov 29, 2020
diff --git a/scopeprotocols/CMakeLists.txt b/scopeprotocols/CMakeLists.txt
@@ -26,6 +26,7 @@ set(SCOPEPROTOCOLS_SOURCES
 	DSIPacketDecoder.cpp
 	DutyCycleMeasurement.cpp
 	DVIDecoder.cpp
+	EmphasisRemovalFilter.cpp
 	Ethernet10BaseTDecoder.cpp
 	Ethernet100BaseTDecoder.cpp
 	Ethernet1000BaseXDecoder.cpp
@@ -78,6 +79,7 @@ set(SCOPEPROTOCOLS_SOURCES
 	SWDDecoder.cpp
 	SWDMemAPDecoder.cpp
 	TachometerFilter.cpp
+	TappedDelayLineFilter.cpp
 	ThresholdFilter.cpp
 	TIEMeasurement.cpp
 	TMDSDecoder.cpp

diff --git a/scopeprotocols/EmphasisRemovalFilter.cpp b/scopeprotocols/EmphasisRemovalFilter.cpp
@@ -0,0 +1,187 @@
+/***********************************************************************************************************************
+*                                                                                                                      *
+* ANTIKERNEL v0.1                                                                                                      *
+*                                                                                                                      *
+* Copyright (c) 2012-2020 Andrew D. Zonenberg                                                                          *
+* All rights reserved.                                                                                                 *
+*                                                                                                                      *
+* Redistribution and use in source and binary forms, with or without modification, are permitted provided that the     *
+* following conditions are met:                                                                                        *
+*                                                                                                                      *
+*    * Redistributions of source code must retain the above copyright notice, this list of conditions, and the         *
+*      following disclaimer.                                                                                           *
+*                                                                                                                      *
+*    * Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the       *
+*      following disclaimer in the documentation and/or other materials provided with the distribution.                *
+*                                                                                                                      *
+*    * Neither the name of the author nor the names of any contributors may be used to endorse or promote products     *
+*      derived from this software without specific prior written permission.                                           *
+*                                                                                                                      *
+* THIS SOFTWARE IS PROVIDED BY THE AUTHORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED   *
+* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL *
+* THE AUTHORS BE HELD LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES        *
+* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR       *
+* BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT *
+* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE       *
+* POSSIBILITY OF SUCH DAMAGE.                                                                                          *
+*                                                                                                                      *
+***********************************************************************************************************************/
+
+#include "scopeprotocols.h"
+#include "EmphasisRemovalFilter.h"
+#include "TappedDelayLineFilter.h"
+
+using namespace std;
+
+////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// Construction / destruction
+
+EmphasisRemovalFilter::EmphasisRemovalFilter(const string& color)
+	: Filter(OscilloscopeChannel::CHANNEL_TYPE_ANALOG, color, CAT_ANALYSIS)
+	, m_dataRateName("Data Rate")
+	, m_emphasisTypeName("Emphasis Type")
+	, m_emphasisAmountName("Emphasis Amount")
+{
+	CreateInput("in");
+
+	m_range = 1;
+	m_offset = 0;
+	m_min = FLT_MAX;
+	m_max = -FLT_MAX;
+
+	m_parameters[m_dataRateName] = FilterParameter(FilterParameter::TYPE_INT, Unit(Unit::UNIT_BITRATE));
+	m_parameters[m_dataRateName].SetIntVal(5e9);
+
+	m_parameters[m_emphasisTypeName] = FilterParameter(FilterParameter::TYPE_ENUM, Unit(Unit::UNIT_COUNTS));
+	m_parameters[m_emphasisTypeName].AddEnumValue("De-emphasis", DE_EMPHASIS);
+	m_parameters[m_emphasisTypeName].SetIntVal(DE_EMPHASIS);
+
+	m_parameters[m_emphasisAmountName] = FilterParameter(FilterParameter::TYPE_FLOAT, Unit(Unit::UNIT_DB));
+	m_parameters[m_emphasisAmountName].SetFloatVal(6);
+}
+
+////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// Factory methods
+
+bool EmphasisRemovalFilter::ValidateChannel(size_t i, StreamDescriptor stream)
+{
+	if(stream.m_channel == NULL)
+		return false;
+
+	if( (i == 0) && (stream.m_channel->GetType() == OscilloscopeChannel::CHANNEL_TYPE_ANALOG) )
+		return true;
+
+	return false;
+}
+
+////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// Accessors
+
+void EmphasisRemovalFilter::ClearSweeps()
+{
+	m_range = 1;
+	m_offset = 0;
+	m_min = FLT_MAX;
+	m_max = -FLT_MAX;
+}
+
+void EmphasisRemovalFilter::SetDefaultName()
+{
+	char hwname[256];
+	snprintf(hwname, sizeof(hwname), "EmphasisRemoval(%s, %s)",
+		GetInputDisplayName(0).c_str(),
+		m_parameters[m_emphasisAmountName].ToString().c_str());
+	m_hwname = hwname;
+	m_displayname = m_hwname;
+}
+
+string EmphasisRemovalFilter::GetProtocolName()
+{
+	return "Emphasis Removal";
+}
+
+bool EmphasisRemovalFilter::IsOverlay()
+{
+	//we create a new analog channel
+	return false;
+}
+
+bool EmphasisRemovalFilter::NeedsConfig()
+{
+	return true;
+}
+
+double EmphasisRemovalFilter::GetVoltageRange()
+{
+	return m_range;
+}
+
+double EmphasisRemovalFilter::GetOffset()
+{
+	return m_offset;
+}
+
+////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// Actual decoder logic
+
+void EmphasisRemovalFilter::Refresh()
+{
+	if(!VerifyAllInputsOKAndAnalog())
+	{
+		SetData(NULL, 0);
+		return;
+	}
+
+	//Only de-emphasis is implemented for now
+	if(m_parameters[m_emphasisTypeName].GetIntVal() != DE_EMPHASIS)
+	{
+		SetData(NULL, 0);
+		return;
+	}
+
+	//Get the input data
+	auto din = GetAnalogInputWaveform(0);
+	size_t len = din->m_samples.size();
+	if(len < 8)
+	{
+		SetData(NULL, 0);
+		return;
+	}
+	m_xAxisUnit = m_inputs[0].m_channel->GetXAxisUnits();
+	m_yAxisUnit = m_inputs[0].m_channel->GetYAxisUnits();
+
+	//Set up output
+	auto cap = new AnalogWaveform;
+	cap->m_timescale = din->m_timescale;
+	cap->m_startTimestamp = din->m_startTimestamp;
+	cap->m_startFemtoseconds = din->m_startFemtoseconds;
+	SetData(cap, 0);
+
+	//Convert data rate to tap delay
+	int64_t tap_delay = round(FS_PER_SECOND / m_parameters[m_dataRateName].GetFloatVal());
+
+	//Calculate the tap values
+	//Reference: "Dealing with De-Emphasis in Jitter Testing", P. Pupalaikis, LeCroy technical brief, 2008
+	const int64_t tap_count = 8;
+	float db = m_parameters[m_emphasisAmountName].GetFloatVal();
+	float coeff = 0.5 * pow(10, -db/20);
+	float c = coeff + 0.5;
+	float p = coeff - 0.5;
+	float p_over_c = p / c;
+	float taps[tap_count] = {0};
+
+	taps[0] = 1/c;
+	for(int64_t i=1; i<tap_count; i++)
+		taps[i] = -p_over_c * taps[i-1];
+
+	//Run the actual filter
+	float vmin;
+	float vmax;
+	TappedDelayLineFilter::DoFilterKernel(tap_count, tap_delay, taps, din, cap, vmin, vmax);
+
+	//Calculate bounds
+	m_max = max(m_max, vmax);
+	m_min = min(m_min, vmin);
+	m_range = (m_max - m_min) * 1.05;
+	m_offset = -( (m_max - m_min)/2 + m_min );
+}
diff --git a/scopeprotocols/EmphasisRemovalFilter.h b/scopeprotocols/EmphasisRemovalFilter.h
@@ -0,0 +1,78 @@
+/***********************************************************************************************************************
+*                                                                                                                      *
+* ANTIKERNEL v0.1                                                                                                      *
+*                                                                                                                      *
+* Copyright (c) 2012-2020 Andrew D. Zonenberg                                                                          *
+* All rights reserved.                                                                                                 *
+*                                                                                                                      *
+* Redistribution and use in source and binary forms, with or without modification, are permitted provided that the     *
+* following conditions are met:                                                                                        *
+*                                                                                                                      *
+*    * Redistributions of source code must retain the above copyright notice, this list of conditions, and the         *
+*      following disclaimer.                                                                                           *
+*                                                                                                                      *
+*    * Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the       *
+*      following disclaimer in the documentation and/or other materials provided with the distribution.                *
+*                                                                                                                      *
+*    * Neither the name of the author nor the names of any contributors may be used to endorse or promote products     *
+*      derived from this software without specific prior written permission.                                           *
+*                                                                                                                      *
+* THIS SOFTWARE IS PROVIDED BY THE AUTHORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED   *
+* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL *
+* THE AUTHORS BE HELD LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES        *
+* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR       *
+* BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT *
+* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE       *
+* POSSIBILITY OF SUCH DAMAGE.                                                                                          *
+*                                                                                                                      *
+***********************************************************************************************************************/
+
+/**
+	@file
+	@author Andrew D. Zonenberg
+	@brief Declaration of EmphasisRemovalFilter
+ */
+#ifndef EmphasisRemovalFilter_h
+#define EmphasisRemovalFilter_h
+
+class EmphasisRemovalFilter : public Filter
+{
+public:
+	EmphasisRemovalFilter(const std::string& color);
+
+	virtual void Refresh();
+
+	virtual bool NeedsConfig();
+	virtual bool IsOverlay();
+
+	virtual void ClearSweeps();
+
+	static std::string GetProtocolName();
+	virtual void SetDefaultName();
+
+	virtual double GetVoltageRange();
+	virtual double GetOffset();
+
+	virtual bool ValidateChannel(size_t i, StreamDescriptor stream);
+
+	PROTOCOL_DECODER_INITPROC(EmphasisRemovalFilter)
+
+	enum EmphasisType
+	{
+		PRE_EMPHASIS,
+		DE_EMPHASIS
+	};
+
+protected:
+
+	float m_min;
+	float m_max;
+	float m_range;
+	float m_offset;
+
+	std::string m_dataRateName;
+	std::string m_emphasisTypeName;
+	std::string m_emphasisAmountName;
+};
+
+#endif
diff --git a/scopeprotocols/JitterSpectrumFilter.cpp b/scopeprotocols/JitterSpectrumFilter.cpp
@@ -185,7 +185,8 @@ void JitterSpectrumFilter::Refresh()
 	size_t capture_duration = din->m_offsets[inlen-1] + din->m_durations[inlen-1];
 	size_t num_uis = extended_samples.size();
 	double ui_width_final = static_cast<double>(capture_duration) / num_uis;
-	LogTrace("Final UI width estimate: %.1f\n", ui_width_final);
+	LogTrace("Capture is %zu UIs, %s\n", num_uis, Unit(Unit::UNIT_FS).PrettyPrint(capture_duration).c_str());
+	LogTrace("Final UI width estimate: %s\n", Unit(Unit::UNIT_FS).PrettyPrint(ui_width_final).c_str());
 
 	//Round size up to next power of two
 	const size_t npoints_raw = extended_samples.size();

diff --git a/scopeprotocols/MovingAverageFilter.cpp b/scopeprotocols/MovingAverageFilter.cpp
@@ -168,4 +168,6 @@ void MovingAverageFilter::Refresh()
 
 	//Copy our time scales from the input
 	cap->m_timescale = din->m_timescale;
+	cap->m_startTimestamp = din->m_startTimestamp;
+	cap->m_startFemtoseconds = din->m_startFemtoseconds;
 }