add gpio and rtc example

examples/CompGpio/CompGpio.ino

@@ -0,0 +1,48 @@
+#include "Nextion.h"
+
+NexGpio gpio;
+NexNumber n0 = NexNumber(0,1,"n0");
+NexNumber n1 = NexNumber(0,3,"n1");
+
+#define   GPIO_PUSH_PORT          1
+#define   GPIO_PWM_PORT           2
+#define   GPIO_PUSH_OUTPUT_MODE   2
+#define   GPIO_PWM_OUT_MODE       3
+#define   CONTROLS_ID             0           //when the modeel is 1 to be valid
+
+uint32_t pwm_value = 0;
+
+void setup() 
+{  
+    nexSerial.begin(115200);
+    gpio.pin_mode(GPIO_PUSH_PORT,GPIO_PUSH_OUTPUT_MODE,CONTROLS_ID);
+    gpio.pin_mode(GPIO_PWM_PORT,GPIO_PWM_OUT_MODE,CONTROLS_ID);
+}
+
+void loop() 
+{
+    if(gpio.digital_read(1) == 0)
+    {
+        gpio.digital_write(GPIO_PUSH_PORT,HIGH);
+        n0.setValue(1);
+    }
+    else
+    {
+        gpio.digital_write(GPIO_PUSH_PORT,LOW);
+        n0.setValue(0);
+    }
+
+    
+    gpio.analog_write(GPIO_PWM_PORT,pwm_value);
+    n1.setValue(pwm_value);
+    if(pwm_value == 100)
+    {
+        pwm_value = 0;
+    }
+    else
+    {
+        pwm_value += 20;
+    }
+
+    delay(1000);
+}

examples/CompRtc/CompRtc.ino

@@ -0,0 +1,19 @@
+#include "Nextion.h"
+
+NexText t0 = NexText(0,1,"t0");
+NexRtc  rtc;
+uint32_t  time[7] = {2016,11,25,12,34,50};
+uint8_t time_buf[30] = {0};
+
+void setup() 
+{
+    nexSerial.begin(115200);
+    rtc.write_rtc_time(time);
+}
+
+void loop() 
+{
+    rtc.read_rtc_time(time_buf,30);
+    t0.setText(time_buf);
+    delay(1000);
+}