--- /dev/null
+#ifndef SILENT_CODE_H
+#define SILENT_CODE_H
+
+/*!
+ *\brief Demangle silent code frames to 6 bit frames
+ */
+extern unsigned char silent_demangle(unsigned char in);
+
+/*!
+ * Combine three mangled paper tape frames into
+ * one 16 bit machine word
+ */
+extern unsigned short combine466(unsigned char* in);
+
+#endif