This demo app demonstrates how to use the necessary JNI layer of code to bridge between the Android app and the kernel.
It is also a useful engineering test app to test a variety of configurations.

Notes about the extra features
The 3 dots icon in the upper right corner
This opens a settings page to configure the port, baud rate, parity, stop bits, flow control, number of data bits
	Port ttymxc0 is the RS232 connector at bottom of the device
	Port ttymxc2 and ttymxc4 are UART ports inside the device's expansion connecter which may be used for built-in custom hardware support

"Display Received Data"
Data received through the port will be shown on the display.  Only useful if using ASCII data, should disable this feature when using binary data, or large amounts of data.

"Echo"
Data received through the port will automatically be transmitted back out the same port.

"Test Flow Control"
Adds a periodic delay in the port read thread, such that it will cause an assertion on the flow control mechanism

"Generate TX Data"
Creates 1,000,000 bytes of data to transmit out the port

"OPEN PORT" button
After the port and app configurations are made, then open the UART port with this button

"CLOSE PORT" button
Close the UART port again to change any of the configurations

"TRANSMIT" button
If "Generate TX Data" is checked, it transmits the 1,000,000 bytes of data.  If not checked, then it only transmits the text that has been manually entered into the "Input message to send" field.


Here are a couple of sample setups between two A3 devices both running this test app
Example Simple Manual Test
  Configure port settings on each device with same parameters.
  Configure other settings on each device as:
    "Dispaly Received Data" - checked
    "Echo" - unchecked
    "Test Flow Control" - unchecked
    "Generate TX Data" - unchecked
  Open port on both devices
  Type some characters into "Input message to send" field on device 1
  Press "TRANSMIT" button on device 1
  Observe that text is now displayed on device 2
    Note: the count of received bytes will show a count of 2 more than the visible characters because of Line Feed and Carriage Return are also sent
  Type some charactesr into "Input message to send" field on device 2
  Press "TRANSMIT" ubtton on device 2
  Observe that text is now displayed on device 1

Example Large Data Transfer with Flow Control
  Configure port settings on each device with same parameters, including flow control configured as hardware.
  Configure other settings on device 1 as:
    "Dispaly Received Data" - unchecked
    "Echo" - unchecked
    "Test Flow Control" - unchecked
    "Generate TX Data" - checked
  Configure other settings on each device 2 as:
    "Dispaly Received Data" - unchecked
    "Echo" - checked
    "Test Flow Control" - checked
    "Generate TX Data" - unchecked
  Open port on both devices
  Press "TRANSMIT" button on device 1
  Observe that data is transfered from device 1 to device 2 and then echoed back to device 1 again.
  Observe occasional stalls in transmit as flow control is asserted    
