diff --git a/docs/source/manual/openfpga_shell/openfpga_commands/setup_commands.rst b/docs/source/manual/openfpga_shell/openfpga_commands/setup_commands.rst
index 73024c458..20505ee82 100644
--- a/docs/source/manual/openfpga_shell/openfpga_commands/setup_commands.rst
+++ b/docs/source/manual/openfpga_shell/openfpga_commands/setup_commands.rst
@@ -127,15 +127,18 @@ write_gsb_to_xml
       - ``--exclude sb``
       - ``--exclude [sb, cbx]``
 
-  .. option:: --gsb_list <string>
+  .. option:: --gsb_names <string>
 
     Specify the name of GSB to be outputted. Users can specify multiple GSBs by using a splitter ``,``.
     When specified, only the GSBs whose names match the list will be outputted to files.
     If not specified, all the GSBs will be outputted.
+
+    .. note:: When option ``--unique`` is enable, the given name of GSBs should match the unique modules! 
+
     For example,
 
-      - ``--gsb_list [gsb_2__4_, gsb_3__2_]``
-      - ``--gsb_list gsb_2__4_``
+      - ``--gsb_names [gsb_2__4_, gsb_3__2_]``
+      - ``--gsb_names gsb_2__4_``
 
   .. option:: --verbose
 
diff --git a/openfpga/src/annotation/rr_gsb_writer_option.cpp b/openfpga/src/annotation/rr_gsb_writer_option.cpp
new file mode 100644
index 000000000..0a12204b1
--- /dev/null
+++ b/openfpga/src/annotation/rr_gsb_writer_option.cpp
@@ -0,0 +1,120 @@
+/******************************************************************************
+ * Memember functions for data structure RRGSBWriterOption
+ ******************************************************************************/
+#include "vtr_assert.h"
+#include "vtr_log.h"
+
+#include "rr_gsb_writer_option.h"
+#include "openfpga_tokenizer.h"
+
+/* begin namespace openfpga */
+namespace openfpga {
+
+/**************************************************
+ * Public Constructors
+ *************************************************/
+RRGSBWriterOption::RRGSBWriterOption() {
+  output_directory_.clear();
+  unique_module_only_ = false;
+  exclude_content_ = {false, false, false, false};
+  gsb_names_.clear();
+  verbose_output_ = false;
+  num_parse_errors_ = 0;
+}
+
+/**************************************************
+ * Public Accessors 
+ *************************************************/
+std::string RRGSBWriterOption::output_directory() const {
+  return output_directory_;
+}
+
+bool RRGSBWriterOption::unique_module_only() const {
+  return unique_module_only_;
+}
+
+bool RRGSBWriterOption::include_rr_info() const {
+  return !exclude_content_[0];
+}
+
+bool RRGSBWriterOption::include_cb_content(const t_rr_type& cb_type) const {
+  if (cb_type == CHANX) {
+    return !exclude_content_[1];
+  }
+  VTR_ASSERT(cb_type == CHANY);
+  return !exclude_content_[2];
+}
+
+bool RRGSBWriterOption::include_sb_content() const {
+  return !exclude_content_[3];
+}
+
+std::vector<std::string> RRGSBWriterOption::include_gsb_names() const {
+  return include_gsb_names_;
+}
+
+bool RRGSBWriterOption::verbose_output() const {
+  return verbose_output_;
+}
+
+/******************************************************************************
+ * Private Mutators
+ ******************************************************************************/
+void RRGSBWriterOption::set_output_directory(const std::string& output_dir) {
+  output_directory_ = output_dir;
+}
+
+void RRGSBWriterOption::set_unique_module_only(const bool& enabled) {
+  unique_module_only_ = enabled;
+}
+
+void RRGSBWriterOption::set_exclude_rr_info(const bool& enabled) {
+  exclude_content_[0] = enabled;
+}
+
+void RRGSBWriterOption::set_exclude_content(const std::string& content) {
+  num_parse_errors_ = 0;
+  /* Split the content using a tokenizer */
+  StringToken tokenizer(content);
+  std::string tokens = tokenizer.split(',');
+  /* Parse each token */
+  std::map<std::string, int> token2index = { {"sb", 3}, {"cbx", 1}, {"cby", 2} };
+  for (std::string token : tokens) {
+    auto result = token2index.find(token);
+    if (result == token2index.end()) {
+      /* Cannot find a valid keyword, error out */
+      std::string keyword_list;
+      for (auto pair : token2index) {
+        keyword_list += pair.first + "|";
+      }
+      keyword_list.pop_back();
+      VTR_LOG_ERROR("Invalid content '" + token + "' to skip, expect [ " + keyword_list + " ]");
+      num_parse_errors_++;
+      continue;
+    }
+    /* Now we should have a valid keyword, assign to designated flag */
+    exclude_content_[result->second] = true;
+  }
+}
+
+void RRGSBWriterOption::set_include_gsb_names(const std::string& gsb_names) {
+  /* Split the content using a tokenizer */
+  StringToken tokenizer(content);
+  gsb_names_ = tokenizer.split(',');
+}
+
+void RRGSBWriterOption::set_verbose_output(const bool& enabled) {
+  verbose_output_ = enabled;
+}
+
+bool RRGSBWriterOption::valid() const {
+  if (output_directory_.empty()) {
+    return false;
+  } 
+  if (num_parse_errors_) {
+    return false;
+  }
+  return true;
+}
+
+} /* end namespace openfpga */
diff --git a/openfpga/src/annotation/rr_gsb_writer_option.h b/openfpga/src/annotation/rr_gsb_writer_option.h
new file mode 100644
index 000000000..2f997c4cb
--- /dev/null
+++ b/openfpga/src/annotation/rr_gsb_writer_option.h
@@ -0,0 +1,65 @@
+#ifndef RR_GSB_WRITER_OPTION_H
+#define RR_GSB_WRITER_OPTION_H
+
+/********************************************************************
+ * Include header files required by the data structure definition
+ *******************************************************************/
+#include <string>
+
+/* Begin namespace openfpga */
+namespace openfpga {
+
+/********************************************************************
+ * Options for RRGSB writer
+ *******************************************************************/
+class RRGSBWriterOption {
+  public: /* Public constructor */
+    /* Set default options */
+    RRGSBWriterOption();
+  public: /* Public accessors */
+    std::string output_directory() const;
+    bool unique_module_only() const;
+    bool include_rr_info() const;
+    bool include_cb_content(const t_rr_type& cb_type) const;
+    bool include_sb_content() const;
+    std::vector<std::string> include_gsb_names() const;
+    bool verbose_output() const;
+  public: /* Public mutators */
+    void set_output_directory(const std::string& output_dir);
+    void set_unique_module_only(const bool& enabled);
+    void set_exclude_rr_info(const bool& enabled);
+    /* Parse the string which contains the content to be excluded
+     * Accepted string format is [sb|cbx|cby]
+     * Allow the use ',' as splitter
+     * For example: sb,cby
+     */
+    void set_exclude_content(const std::string& content);
+    void set_include_gsb_names(const std::string& gsb_names);
+    void set_verbose_output(const bool& enabled);
+  public: /* Public validators */
+    /* Check if the following internal data is valid or not:
+     * - output directory is assigned
+     * - no parsing errors
+     */
+    bool valid() const;
+  private: /* Internal Data */
+    std::string output_directory_;
+    bool unique_module_only_;
+    /* Flags to mark what content to be skipped when outputting: 
+     * 0 : rr_info
+     * 1 : cbx
+     * 2 : cby
+     * 3 : sb
+     */
+    std::array<bool, 4> exclude_content_;
+
+    std::vector<std::string> gsb_names_;
+    bool verbose_output_;
+
+    /* A flag to indicate if the data parse is invalid or not */
+    int num_parse_errors_;
+};
+
+} /* End namespace openfpga*/
+
+#endif
diff --git a/openfpga/src/annotation/write_xml_device_rr_gsb.cpp b/openfpga/src/annotation/write_xml_device_rr_gsb.cpp
index e778f7f49..7039647a0 100644
--- a/openfpga/src/annotation/write_xml_device_rr_gsb.cpp
+++ b/openfpga/src/annotation/write_xml_device_rr_gsb.cpp
@@ -182,7 +182,12 @@ void write_rr_switch_block_to_xml(const std::string fname_prefix,
                                   const VprDeviceAnnotation& vpr_device_annotation,
                                   const RRGraph& rr_graph,
                                   const RRGSB& rr_gsb,
-                                  const bool& verbose) {
+                                  const RRGSBWriterOption& options) {
+
+  /* If there is a list of gsb list, we skip those which are not in the list */
+  if (!include_gsb_names.empty() && include_gsb_names.end() != std::find(include_gsb_names.begin(), include_gsb_names.end(), curr_gsb_name()
+    write_rr_switch_block_to_xml(xml_dir_name, vpr_device_grid, vpr_device_annotation, rr_graph, rr_gsb, options);
+
   /* Prepare file name */
   std::string fname(fname_prefix);
   vtr::Point<size_t> gsb_coordinate(rr_gsb.get_sb_x(), rr_gsb.get_sb_y());
@@ -224,49 +229,133 @@ void write_rr_switch_block_to_xml(const std::string fname_prefix,
   fp.close();
 }
 
+/***************************************************************************************
+ * Output internal structure (only the connection block part) of a RRGSB to XML format 
+ ***************************************************************************************/
+static 
+void write_rr_connection_block_to_xml(const std::string fname_prefix,
+                                      const DeviceGrid& vpr_device_grid,
+                                      const VprDeviceAnnotation& vpr_device_annotation,
+                                      const RRGraph& rr_graph,
+                                      const RRGSB& rr_gsb,
+                                      const t_rr_type& cb_type,
+                                      const RRGSBWriterOption& options) {
+
+  /* If there is a list of gsb list, we skip those which are not in the list */
+  if (!include_gsb_names.empty() && include_gsb_names.end() != std::find(include_gsb_names.begin(), include_gsb_names.end(), curr_gsb_name()
+    write_rr_switch_block_to_xml(xml_dir_name, vpr_device_grid, vpr_device_annotation, rr_graph, rr_gsb, options);
+
+  /* Prepare file name */
+  std::string fname(fname_prefix);
+  vtr::Point<size_t> cb_coordinate(rr_gsb.get_cb_x(cb_type), rr_gsb.get_cb_y(cb_type));
+  fname += generate_connection_block_module_name(cb_type, cb_coordinate);
+  fname += ".xml";
+
+  VTR_LOGV(verbose,
+           "Output internal structure of Connection Block to '%s'\n",
+           fname.c_str());
+
+  /* Create a file handler*/
+  std::fstream fp;
+  /* Open a file */
+  fp.open(fname, std::fstream::out | std::fstream::trunc);
+
+  /* Validate the file stream */
+  check_file_stream(fname.c_str(), fp);
+
+  /* Output location of the Switch Block */
+  fp << "<rr_cb x=\"" << rr_gsb.get_cb_x(cb_type) << "\" y=\"" << rr_gsb.get_cb_y(cb_type) << "\""
+     << " num_sides=\"" << rr_gsb.get_num_sides() << "\">" << std::endl;
+
+  /* Output each side */ 
+  for (size_t side = 0; side < rr_gsb.get_cb_ipin_sides(cb_type); ++side) {
+    SideManager gsb_side_manager(side);
+    enum e_side gsb_side = gsb_side_manager.get_side();
+   
+    /* IPIN nodes and related connections */
+    write_rr_gsb_ipin_connection_to_xml(fp, rr_graph, rr_gsb, gsb_side);
+  }
+
+  fp << "</rr_cb>" 
+     << std::endl;
+
+  /* close a file */
+  fp.close();
+}
+
+
 /***************************************************************************************
  * Output internal structure (only the switch block part) of all the RRGSBs
  * in a DeviceRRGSB  to XML format 
  ***************************************************************************************/
-void write_device_rr_gsb_to_xml(const char* sb_xml_dir, 
-                                const DeviceGrid& vpr_device_grid,
+void write_device_rr_gsb_to_xml(const DeviceGrid& vpr_device_grid,
                                 const VprDeviceAnnotation& vpr_device_annotation,
                                 const RRGraph& rr_graph,
                                 const DeviceRRGSB& device_rr_gsb,
-                                const bool& unique,
-                                const bool& verbose) {
-  std::string xml_dir_name = format_dir_path(std::string(sb_xml_dir));
+                                const RRGSBWriterOption& options) {
+  std::string xml_dir_name = format_dir_path(options.output_directory);
 
   /* Create directories */
   create_directory(xml_dir_name);
 
   vtr::Point<size_t> sb_range = device_rr_gsb.get_gsb_range();
 
-  size_t gsb_counter = 0;
+  size_t sb_counter = 0;
+  std::map<t_rr_type, size_t> cb_counters = 0;
+  std::map<t_rr_type, std::string> cb_names = { {CHANX, "X-direction"}, {CHANY, "Y-direction"} };
+
+  std::vector<std::string> include_gsb_names = options.include_gsb_names();
 
   /* For each switch block, an XML file will be outputted */
-  if (unique) {
+  if (options.unique_module_only()) {
     /* Only output unique GSB modules */
     VTR_LOG("Only output unique GSB modules to XML\n");
     for (size_t igsb = 0; igsb < device_rr_gsb.get_num_gsb_unique_module(); ++igsb) {
-      const RRGSB& rr_gsb = device_rr_gsb.get_gsb_unique_module(igsb);
-      write_rr_switch_block_to_xml(xml_dir_name, vpr_device_grid, vpr_device_annotation, rr_graph, rr_gsb, verbose);
-      gsb_counter++;
+      const RRGSB& rr_gsb = device_rr_gsb.get_sb_unique_module(igsb);
+      /* Write CBx, CBy, SB on need */
+      if (options.include_sb_content()) {
+        write_rr_switch_block_to_xml(xml_dir_name, vpr_device_grid, vpr_device_annotation, rr_graph, rr_gsb, options);
+      }
+      sb_counter++;
+    }
+    for (size_t igsb = 0; igsb < device_rr_gsb.get_num_gsb_unique_module(); ++igsb) {
+      const RRGSB& rr_gsb = device_rr_gsb.get_sb_unique_module(igsb);
+      for (t_rr_type cb_type : {CHANX, CHANY}) {
+        if (options.include_cb_content(cb_type)) {
+          write_rr_connection_block_to_xml(xml_dir_name, vpr_device_grid, vpr_device_annotation, rr_graph, rr_gsb, cb_type, options);
+          cb_counters[cb_type]++;
+        }
+      }
     } 
   } else {
     /* Output all GSB instances in the fabric (some instances may share the same module) */
     for (size_t ix = 0; ix < sb_range.x(); ++ix) {
       for (size_t iy = 0; iy < sb_range.y(); ++iy) {
         const RRGSB& rr_gsb = device_rr_gsb.get_gsb(ix, iy);
-        write_rr_switch_block_to_xml(xml_dir_name, vpr_device_grid, vpr_device_annotation, rr_graph, rr_gsb, verbose);
-        gsb_counter++;
+        /* Write CBx, CBy, SB on need */
+        if (options.include_sb_content()) {
+          write_rr_switch_block_to_xml(xml_dir_name, vpr_device_grid, vpr_device_annotation, rr_graph, rr_gsb, options);
+          sb_counter++;
+        }
+        for (t_rr_type cb_type : {CHANX, CHANY}) {
+          if (options.include_cb_content(cb_type)) {
+            write_rr_connection_block_to_xml(xml_dir_name, vpr_device_grid, vpr_device_annotation, rr_graph, rr_gsb, cb_type, options);
+            cb_counters[cb_type]++;
+          }
+        }
       }
     }
   }
 
-  VTR_LOG("Output %lu XML files to directory '%s'\n",
-          gsb_counter,
+  VTR_LOG("Output %lu Switch blocks to XML files under directory '%s'\n",
+          sb_counter,
           xml_dir_name.c_str());
+  for (t_rr_type cb_type : {CHANX, CHANY}) {
+    VTR_LOG("Output %lu %s Connection blocks to XML files under directory '%s'\n",
+            cb_counters[cb_type],
+            cb_names[cb_type].c_str(),
+            xml_dir_name.c_str());
+  }
 }
 
 } /* end namespace openfpga */
diff --git a/openfpga/src/annotation/write_xml_device_rr_gsb.h b/openfpga/src/annotation/write_xml_device_rr_gsb.h
index 06d647d7a..077e6ee2f 100644
--- a/openfpga/src/annotation/write_xml_device_rr_gsb.h
+++ b/openfpga/src/annotation/write_xml_device_rr_gsb.h
@@ -9,6 +9,7 @@
 #include "device_grid.h"
 #include "vpr_device_annotation.h"
 #include "device_rr_gsb.h"
+#include "rr_gsb_writer_option.h"
 
 /********************************************************************
  * Function declaration
@@ -17,13 +18,11 @@
 /* begin namespace openfpga */
 namespace openfpga {
 
-void write_device_rr_gsb_to_xml(const char* sb_xml_dir,
-                                const DeviceGrid& vpr_device_grid,
+void write_device_rr_gsb_to_xml(const DeviceGrid& vpr_device_grid,
                                 const VprDeviceAnnotation& vpr_device_annotation,
                                 const RRGraph& rr_graph,
                                 const DeviceRRGSB& device_rr_gsb,
-                                const bool& unique,
-                                const bool& verbose);
+                                const RRGSBWriterOption& options);
 
 } /* end namespace openfpga */
 
diff --git a/openfpga/src/base/openfpga_setup_command.cpp b/openfpga/src/base/openfpga_setup_command.cpp
index b645a33ac..b0d24c231 100644
--- a/openfpga/src/base/openfpga_setup_command.cpp
+++ b/openfpga/src/base/openfpga_setup_command.cpp
@@ -213,6 +213,17 @@ ShellCommandId add_openfpga_write_gsb_command(openfpga::Shell<OpenfpgaContext>&
   /* Add an option '--unique' */
   shell_cmd.add_option("unique", false, "Only output unique GSB blocks");
 
+  /* Add an option '--exclude_rr_info' */
+  shell_cmd.add_option("exclude_rr_info", false, "Exclude routing resource graph information from output files, e.g., node id as well as other attributes. This is useful to check the connection inside GSBs purely.");
+
+  /* Add an option '--exclude'*/
+  CommandOptionId opt_exclude = shell_cmd.add_option("exclude", false, "Exclude part of the GSB data to be outputted. Can be [``sb``|``cbx``|``cby``]. Users can exclude multiple parts by using a splitter ``,``");
+  shell_cmd.set_option_require_value(opt_exclude, openfpga::OPT_STRING);
+
+  /* Add an option '--gsb_names'*/
+  CommandOptionId opt_gsb_names = shell_cmd.add_option("gsb_names", false, "Specify the name of GSB to be outputted. Users can specify multiple GSBs by using a splitter ``,``");
+  shell_cmd.set_option_require_value(opt_gsb_names, openfpga::OPT_STRING);
+
   /* Add an option '--verbose' */
   shell_cmd.add_option("verbose", false, "Show verbose outputs");
 
diff --git a/openfpga/src/base/openfpga_write_gsb.cpp b/openfpga/src/base/openfpga_write_gsb.cpp
index cab50bd3d..6ec4a19e8 100644
--- a/openfpga/src/base/openfpga_write_gsb.cpp
+++ b/openfpga/src/base/openfpga_write_gsb.cpp
@@ -34,17 +34,25 @@ int write_gsb(const OpenfpgaContext& openfpga_ctx,
   VTR_ASSERT(false == cmd_context.option_value(cmd, opt_file).empty());
 
   CommandOptionId opt_unique = cmd.option("unique");
+  CommandOptionId opt_exclude_rr_info = cmd.option("exclude_rr_info");
+  CommandOptionId opt_exclude = cmd.option("exclude");
+  CommandOptionId opt_gsb_names = cmd.option("gsb_names");
   CommandOptionId opt_verbose = cmd.option("verbose");
 
-  std::string sb_file_name = cmd_context.option_value(cmd, opt_file);
+  /* Build the options for the writer */
+  RRGSBWriterOption options;
+  options.set_output_directory(cmd_context.option_value(cmd, opt_file));
+  options.set_unique_module_only(cmd_context.option_enable(cmd, opt_unique));
+  options.set_exclude_rr_info(cmd_context.option_enable(cmd, opt_exclude_rr_info));
+  options.set_exclude_content(cmd_context.option_value(cmd, opt_exclude));
+  options.set_include_gsb_list(cmd_context.option_value(cmd, opt_gsb_names));
+  options.set_verbose_output(cmd_context.option_enable(cmd, opt_verbose));
 
-  write_device_rr_gsb_to_xml(sb_file_name.c_str(),
-                             g_vpr_ctx.device().grid,
+  write_device_rr_gsb_to_xml(g_vpr_ctx.device().grid,
                              openfpga_ctx.vpr_device_annotation(),
                              g_vpr_ctx.device().rr_graph,
                              openfpga_ctx.device_rr_gsb(),
-                             cmd_context.option_enable(cmd, opt_unique),
-                             cmd_context.option_enable(cmd, opt_verbose));
+                             options);
 
   /* TODO: should identify the error code from internal function execution */
   return CMD_EXEC_SUCCESS;