Now the Crash reporter uses the configured BAUDRATE to send the report through the Programming port. And also shows the traceback of functions as discussed. For that latest feature to work, you need to compile the project with -funwind-tables and -mpoke-function-name compiler flags

Marlin/src/HAL/HAL_DUE/backtrace/backtrace.h

@@ -0,0 +1,53 @@
+/*
+ * Libbacktrace
+ * Copyright 2015 Stephen Street <stephen@redrocketcomputing.com>
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This library was modified and adapted to be used in Marlin 3D printer
+ * firmware as backtracer for exceptions for debugging purposes in 2018
+ * by Eduardo José Tagle.
+ */
+
+/*
+ * For this library to work, you need to compile with the following options
+ * -funwind-tables => So we will have unwind information to perform the stack trace
+ * -mpoke-function-name => So we will have function names in the trace
+ */
+
+#ifndef _BACKTRACE_H_
+#define _BACKTRACE_H_
+
+#include <stdint.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* A frame */
+typedef struct backtrace_frame {
+  uint32_t fp;
+  uint32_t sp;
+  uint32_t lr;
+  uint32_t pc;
+} backtrace_frame_t;
+
+/* A backtrace */
+typedef struct backtrace {
+  void *function;
+  void *address;
+  const char *name;
+} backtrace_t;
+
+typedef void (*backtrace_dump_fn_t)(int idx, const backtrace_t* bte, void* ctx);
+
+/* Perform a backtrace, given the specified stack start frame */
+int backtrace_dump(backtrace_frame_t *startframe, backtrace_dump_fn_t fn, void* ctx );
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif // _BACKTRACE_H_