//Inclass Exercise (UART)
//R. Traylor 11.5.2022

In this inclass exercise we will conduct two "experiments". 
The first experiment establishes that we have a working setup.

1. (a) Get the necessary code via wget. Briefly look at the code
       in uart_rxtx.c.
   (b) Remove any jumpers on J7 or J9. 
   (c) Put a jumper between Port E, bits zero and one. This
       connects the UART0 TXDO and RXD0 ports. This will allow our
       UART to talk to itself. 
   (d) Compile and download to the mega128 board. 
   (e) You should see the "Hi! Delbert: #" message if things
       are working.

2. (a) Edit uart_rxtx.c to send a personal message of your choice.
   (b) Connect your mega128 board to a neighbors by connecting 
       UART0 up as shown below.

               Board 1                                      Board2
               -------                                      ------
        TXD0 (port E, bit 1) --------\     /-------- TXD0 (port E, bit 1)
                                  /---\---/
        RXD0 (port E, bit 0) ----/     \------------ RXD0 (port E, bit 0)
        Gnd   -------------------------------------- Gnd

   (c) You should be able to see your message on your neighbor's 
       mega128 board.

[The following experiment has not been tested. Let's see what happens!]
3. (a) Remove the existing jumpers.
   (b) Put jumpers in at J10, J11.
   (c) Change your code to use USART1 instead of USART0, and to use 1200
       baud. See uart_functions.c for initalization routines and baud
       rate setting. A macro is used to compute the baudrate, no need to
       do it yourself.
   (c) Point the IR port for each board towards the other. They should
       be able to communicate.

For checking off this inclass activity, just part 1 will be checked.