Modify the file main.cpp for M487

Revision:
0:a67fc999dd68
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/NuMaker-mbed-NuBrick/NuBrickField.h	Fri Sep 29 05:44:02 2017 +0000
@@ -0,0 +1,77 @@
+/* mbed Microcontroller Library
+ * Copyright (c) 2016 ARM Limited
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#ifndef NUBRICK_FIELD_H
+#define NUBRICK_FIELD_H
+
+#include "mbed.h"
+#include <utility>
+
+/** An open field of a NuMaker Brick device
+ *
+ * @Note Synchronization level: Thread safe
+ *
+ */
+class NuBrickField {
+    friend class NuBrickMaster;
+    
+public:
+    typedef std::pair<uint16_t, const char *> IndexName;
+    
+public:
+    NuBrickField(uint8_t field_index, const char *name):
+        _field_index(field_index),
+        _length(0), 
+        _minimum(0),
+        _maximum(0),
+        _value(0),
+        _name(name) {
+        // Do nothing
+    };
+    
+    /** Get minimum value of the open field of a NuBrick device
+     */
+    uint16_t get_minimum(void) {
+        return _minimum;
+    };
+    
+    /** Get maximum value of the open field of a NuBrick device
+     */
+    uint16_t get_maximum(void) {
+        return _maximum;
+    }
+    
+    /** Get value of the open field of a NuBrick device
+     */
+    uint16_t get_value(void) {
+        return _value;
+    }
+    
+    /** Set value of the open field of a NuBrick device
+     */
+    void set_value(uint16_t value) {
+        _value = value;
+    }
+    
+private:
+    uint16_t        _field_index;
+    uint16_t        _length;
+    uint16_t        _minimum;
+    uint16_t        _maximum;
+    uint16_t        _value;
+    const char *    _name;
+};
+
+#endif