Add i2c examples

Signed-off-by: Bigbits <btx000@qq.com>

libraries/Wire/examples/i2c_rxtx/i2c_rxtx.ino

@@ -0,0 +1,25 @@
+
+#include <Wire.h>
+
+void setup() {
+  Serial.begin (115200);
+
+  // Leonardo: wait for serial port to connect
+  while (!Serial) 
+    {
+    }
+
+  Serial.println ();
+  Serial.println ("I2C Testing ...");
+  byte count = 0;
+  
+  Wire.begin();
+  Wire.beginTransmission(0x3C);
+  Wire.write(0x80);
+  Wire.write(0xAF);
+  Wire.endTransmission();
+  Serial.println ("Done.");
+
+}  // end of setup
+
+void loop() {}

libraries/Wire/examples/i2c_scaner/i2c_scaner.ino

@@ -0,0 +1,40 @@
+// I2C Scanner
+// Written by Nick Gammon
+// Date: 20th April 2011
+
+#include <Wire.h>
+
+void setup() {
+  Serial.begin (115200);
+
+  // Leonardo: wait for serial port to connect
+  while (!Serial) 
+    {
+    }
+
+  Serial.println ();
+  Serial.println ("I2C scanner. Scanning ...");
+  byte count = 0;
+  
+  Wire.begin();
+  for (byte i = 8; i < 120; i++)
+  {
+    Wire.beginTransmission (i);
+    if (Wire.endTransmission () == 0)
+      {
+      Serial.print ("Found address: ");
+      Serial.print (i, DEC);
+      Serial.print (" (0x");
+      Serial.print (i, HEX);
+      Serial.println (")");
+      count++;
+      //delay (1);  // maybe unneeded?
+      } // end of good response
+  } // end of for loop
+  Serial.println ("Done.");
+  Serial.print ("Found ");
+  Serial.print (count, DEC);
+  Serial.println (" device(s).");
+}  // end of setup
+
+void loop() {}

libraries/Wire/library.properties

@@ -6,4 +6,4 @@ sentence=Allows the communication between devices or sensors connected via Two W
 paragraph=
 category=Signal Input/Output
 url=http://arduino.cc/en/Reference/Wire
-architectures=riscv
+architectures=k210