Add and update I2C topics (#602)

* Add and update I2C topics

* Throw in some edits for the serial buffer apis

* Add an example to serial read buffer

docs/reference/serial/write-buffer.md

@@ -1,4 +1,4 @@
-# Serial Write Buffer
+# write Buffer
 
 Write a buffer to the [serial](/device/serial) port.
 
@@ -6,6 +6,22 @@ Write a buffer to the [serial](/device/serial) port.
 serial.writeBuffer(pins.createBuffer(0));
 ```
 
+You place your data characters into an existing buffer. All of the data, the length of the buffer, is written to the serial port.
+
 ## Parameters
 
-* `buffer` is the buffer to write to the serial port
+* **buffer**: a [buffer](/types/buffer) to write to the serial port.
+
+## Example
+
+Read some characters of data from a device connected to the I2C pins. Write the data to the serial port.
+
+```blocks
+pins.i2cWriteNumber(132, NumberFormat.UInt8LE, 0);
+let i2cBuffer = pins.i2cReadBuffer(132, 16, false);
+serial.writeBuffer(i2cBuffer);
+```
+
+## See also
+
+[read buffer](/reference/serial/read-buffer)