diff --git a/lib/fluxsink/fl2fluxsink.cc b/lib/fluxsink/fl2fluxsink.cc
index 69bde688..d34052c0 100644
--- a/lib/fluxsink/fl2fluxsink.cc
+++ b/lib/fluxsink/fl2fluxsink.cc
@@ -19,28 +19,35 @@ class Fl2FluxSink : public FluxSink
 public:
 	Fl2FluxSink(const Fl2FluxSinkProto& lconfig):
 		_config(lconfig),
-		_of(lconfig.filename())
+		_of(lconfig.filename(), std::ios::out | std::ios::binary)
 	{
 		if (!_of.is_open())
 			Error() << "cannot open output file";
-		_proto.set_version(FluxFileVersion::VERSION_1);
 	}
 
 	~Fl2FluxSink()
 	{
-		std::cerr << "FL2: writing output file\n";
-		if (!_proto.SerializeToOstream(&_of))
+		FluxFileProto proto;
+		proto.set_version(FluxFileVersion::VERSION_1);
+		for (const auto& e : _data)
+		{
+			auto track = proto.add_track();
+			track->set_cylinder(e.first.first);
+			track->set_head(e.first.second);
+			track->set_flux(e.second);
+		}
+
+		if (!proto.SerializeToOstream(&_of))
 			Error() << "unable to write output file";
 		_of.close();
+		if (_of.fail())
+			Error() << "FL2 write I/O error: " << strerror(errno);
 	}
 
 public:
 	void writeFlux(int cylinder, int head, Fluxmap& fluxmap)
 	{
-		auto track = _proto.add_track();
-		track->set_cylinder(cylinder);
-		track->set_head(head);
-		track->set_flux(fluxmap.rawBytes());
+		_data[std::make_pair(cylinder, head)] = fluxmap.rawBytes();
 	}
 
 	operator std::string () const
@@ -51,7 +58,7 @@ public:
 private:
 	const Fl2FluxSinkProto& _config;
 	std::ofstream _of;
-	FluxFileProto _proto;
+	std::map<std::pair<unsigned, unsigned>, Bytes> _data;
 };
 
 std::unique_ptr<FluxSink> FluxSink::createFl2FluxSink(const Fl2FluxSinkProto& config)
diff --git a/lib/fluxsource/cwffluxsource.cc b/lib/fluxsource/cwffluxsource.cc
index bf383e0e..033e4364 100644
--- a/lib/fluxsource/cwffluxsource.cc
+++ b/lib/fluxsource/cwffluxsource.cc
@@ -139,77 +139,3 @@ std::unique_ptr<FluxSource> FluxSource::createCwfFluxSource(const CwfFluxSourceP
 {
     return std::unique_ptr<FluxSource>(new CwfFluxSource(config));
 }
-
-#if 0
-#include "globals.h"
-#include "fluxmap.h"
-#include "sql.h"
-#include "bytes.h"
-#include "protocol.h"
-
-static std::ifstream inputFile;
-static sqlite3* outputDb;
-static CwfHeader header;
-static double clockRate;
-
-static void syntax()
-{
-    std::cout << "Syntax: fluxengine convert cwftoflux <cwffile> <fluxfile>\n";
-    exit(0);
-}
-
-static void check_for_error()
-{
-    if (inputFile.fail())
-        Error() << fmt::format("I/O error: {}", strerror(errno));
-}
-
-static void read_header()
-{
-}
-
-static void read_track()
-{
-    CwfTrack trackheader;
-    inputFile.read((char*) &trackheader, sizeof(trackheader));
-    check_for_error();
-
-    uint32_t length = Bytes(trackheader.length, 4).reader().read_le32() - sizeof(CwfTrack);
-    unsigned track_number = trackheader.track * header.step;
-    std::cout << fmt::format("{}.{}: {} input bytes; ", track_number, trackheader.side, length)
-        << std::flush;
-
-    std::vector<uint8_t> inputdata(length);
-    inputFile.read((char*) &inputdata[0], length);
-    check_for_error();
-
-
-    std::cout << fmt::format(" {} ms in {} output bytes\n",
-        fluxmap.duration() / 1e6, fluxmap.bytes());
-    sqlWriteFlux(outputDb, track_number, trackheader.side, fluxmap);
-}
-
-int mainConvertCwfToFlux(int argc, const char* argv[])
-{
-    if (argc != 3)
-        syntax();
-    
-    inputFile.open(argv[1], std::ios::in | std::ios::binary);
-    if (!inputFile.is_open())
-		Error() << fmt::format("cannot open input file '{}'", argv[1]);
-
-    outputDb = sqlOpen(argv[2], SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE);
-    sqlPrepareFlux(outputDb);
-    sqlWriteIntProperty(outputDb, "version", FLUX_VERSION_CURRENT);
-    sqlStmt(outputDb, "BEGIN;");
-
-    read_header();
-    inputFile.seekg(sizeof(header), std::ios::beg);
-    for (unsigned i=0; i<(header.cylinders*header.sides); i++)
-        read_track();
-
-    sqlStmt(outputDb, "COMMIT;");
-    sqlClose(outputDb);
-    return 0;
-}
-#endif
diff --git a/lib/fluxsource/fl2fluxsource.cc b/lib/fluxsource/fl2fluxsource.cc
new file mode 100644
index 00000000..05fa4392
--- /dev/null
+++ b/lib/fluxsource/fl2fluxsource.cc
@@ -0,0 +1,55 @@
+#include "globals.h"
+#include "fluxmap.h"
+#include "lib/fluxsource/fluxsource.pb.h"
+#include "lib/fl2.pb.h"
+#include "fluxsource/fluxsource.h"
+#include "proto.h"
+#include "fmt/format.h"
+#include <fstream>
+
+class Fl2FluxSource : public FluxSource
+{
+public:
+    Fl2FluxSource(const Fl2FluxSourceProto& config):
+		_config(config)
+    {
+		std::ifstream ifs(_config.filename(), std::ios::in | std::ios::binary);
+		if (!ifs.is_open())
+			Error() << fmt::format("cannot open input file '{}': {}",
+				_config.filename(), strerror(errno));
+
+		if (!_proto.ParseFromIstream(&ifs))
+			Error() << "unable to read input file";
+	}
+
+public:
+    std::unique_ptr<Fluxmap> readFlux(int cylinder, int head)
+    {
+		for (const auto& track : _proto.track())
+		{
+			if ((track.cylinder() == cylinder) && (track.head() == head))
+				return std::make_unique<Fluxmap>(track.flux());
+		}
+
+		return std::unique_ptr<Fluxmap>();
+    }
+
+    void recalibrate() {}
+
+private:
+	void check_for_error(std::ifstream& ifs)
+	{
+		if (ifs.fail())
+			Error() << fmt::format("FL2 read I/O error: {}", strerror(errno));
+	}
+
+private:
+    const Fl2FluxSourceProto& _config;
+	FluxFileProto _proto;
+};
+
+std::unique_ptr<FluxSource> FluxSource::createFl2FluxSource(const Fl2FluxSourceProto& config)
+{
+    return std::unique_ptr<FluxSource>(new Fl2FluxSource(config));
+}
+
diff --git a/lib/fluxsource/fluxsource.cc b/lib/fluxsource/fluxsource.cc
index 67658ff6..768eeeea 100644
--- a/lib/fluxsource/fluxsource.cc
+++ b/lib/fluxsource/fluxsource.cc
@@ -39,6 +39,9 @@ std::unique_ptr<FluxSource> FluxSource::create(const FluxSourceProto& config)
 		case FluxSourceProto::kCwf:
 			return createCwfFluxSource(config.cwf());
 
+		case FluxSourceProto::kFl2:
+			return createFl2FluxSource(config.fl2());
+
 		default:
 			Error() << "bad input disk configuration";
 			return std::unique_ptr<FluxSource>();
@@ -52,6 +55,7 @@ void FluxSource::updateConfigForFilename(FluxSourceProto* proto, const std::stri
 		{ std::regex("^(.*\\.flux)$"),     [&](const auto& s) { proto->set_fluxfile(s); }},
 		{ std::regex("^(.*\\.scp)$"),      [&](const auto& s) { proto->mutable_scp()->set_filename(s); }},
 		{ std::regex("^(.*\\.cwf)$"),      [&](const auto& s) { proto->mutable_cwf()->set_filename(s); }},
+		{ std::regex("^(.*\\.fl2)$"),      [&](const auto& s) { proto->mutable_fl2()->set_filename(s); }},
 		{ std::regex("^erase:$"),          [&](const auto& s) { proto->mutable_erase(); }},
 		{ std::regex("^kryoflux:(.*)$"),   [&](const auto& s) { proto->mutable_kryoflux()->set_directory(s); }},
 		{ std::regex("^testpattern:(.*)"), [&](const auto& s) { proto->mutable_test_pattern(); }},
diff --git a/lib/fluxsource/fluxsource.h b/lib/fluxsource/fluxsource.h
index 38cb4a14..9ea0f7b1 100644
--- a/lib/fluxsource/fluxsource.h
+++ b/lib/fluxsource/fluxsource.h
@@ -5,6 +5,7 @@
 
 class CwfFluxSourceProto;
 class EraseFluxSourceProto;
+class Fl2FluxSourceProto;
 class FluxSourceProto;
 class FluxSpec;
 class Fluxmap;
@@ -21,6 +22,7 @@ public:
 private:
     static std::unique_ptr<FluxSource> createCwfFluxSource(const CwfFluxSourceProto& config);
     static std::unique_ptr<FluxSource> createEraseFluxSource(const EraseFluxSourceProto& config);
+    static std::unique_ptr<FluxSource> createFl2FluxSource(const Fl2FluxSourceProto& config);
     static std::unique_ptr<FluxSource> createHardwareFluxSource(const HardwareFluxSourceProto& config);
     static std::unique_ptr<FluxSource> createKryofluxFluxSource(const KryofluxFluxSourceProto& config);
     static std::unique_ptr<FluxSource> createScpFluxSource(const ScpFluxSourceProto& config);
diff --git a/lib/fluxsource/fluxsource.proto b/lib/fluxsource/fluxsource.proto
index 1cf49008..c5ce6243 100644
--- a/lib/fluxsource/fluxsource.proto
+++ b/lib/fluxsource/fluxsource.proto
@@ -29,10 +29,15 @@ message ScpFluxSourceProto {
 }
 
 message CwfFluxSourceProto {
-	optional string filename = 1 [default = "flux.xwf",
+	optional string filename = 1 [default = "flux.cwf",
 		(help) = ".cwf file to read flux from"];
 }
 
+message Fl2FluxSourceProto {
+	optional string filename = 1 [default = "flux.fl2",
+		(help) = ".fl2 file to read flux from"];
+}
+
 message FluxSourceProto {
 	oneof source {
 		string fluxfile = 1 [default = "name of source flux file"];
@@ -42,6 +47,7 @@ message FluxSourceProto {
 		KryofluxFluxSourceProto kryoflux = 5;
 		ScpFluxSourceProto scp = 6;
 		CwfFluxSourceProto cwf = 7;
+		Fl2FluxSourceProto fl2 = 8;
 	}
 }
 
diff --git a/lib/globals.h b/lib/globals.h
index ab10a54b..3aaab4c2 100644
--- a/lib/globals.h
+++ b/lib/globals.h
@@ -18,6 +18,10 @@
 #define mkdir(A, B) _mkdir(A)
 #endif
 
+template <class T>
+static inline std::vector<T> vector_of(T item)
+{ return std::vector<T> { item }; }
+
 typedef double nanoseconds_t;
 class Bytes;
 
diff --git a/mkninja.sh b/mkninja.sh
index 10956e5e..0517d992 100644
--- a/mkninja.sh
+++ b/mkninja.sh
@@ -270,6 +270,10 @@ encodedecodetest() {
     echo "    format=$format"
     echo "    configs=$*"
     echo "    fluxx=scp"
+    echo "build $OBJDIR/$format.encodedecode.fl2.stamp : encodedecode | fluxengine$EXTENSION scripts/encodedecodetest.sh $*"
+    echo "    format=$format"
+    echo "    configs=$*"
+    echo "    fluxx=fl2"
 }
 
 buildlibrary libagg.a \
@@ -359,6 +363,7 @@ buildlibrary libbackend.a \
     lib/fluxsink/vcdfluxsink.cc \
     lib/fluxsource/cwffluxsource.cc \
     lib/fluxsource/erasefluxsource.cc \
+    lib/fluxsource/fl2fluxsource.cc \
     lib/fluxsource/fluxsource.cc \
     lib/fluxsource/hardwarefluxsource.cc \
     lib/fluxsource/kryoflux.cc \
diff --git a/protocol.h b/protocol.h
index 2d04c718..6def92f0 100644
--- a/protocol.h
+++ b/protocol.h
@@ -88,7 +88,8 @@ enum
 enum
 {
     F_BIT_PULSE = 0x80,
-    F_BIT_INDEX = 0x40
+    F_BIT_INDEX = 0x40,
+	F_DESYNC = 0xc0
 };
 
 struct frame_header
diff --git a/src/fe-seek.cc b/src/fe-seek.cc
index 6c11fbb5..68c6b512 100644
--- a/src/fe-seek.cc
+++ b/src/fe-seek.cc
@@ -1,7 +1,7 @@
 #include "globals.h"
 #include "flags.h"
 #include "usb/usb.h"
-#include "fluxsource/fluxsource.cc"
+#include "fluxsource/fluxsource.h"
 #include "proto.h"
 #include "protocol.h"