Need help sending 2 bytes!

[AussieSusan]

You will need to be sure to read the first value before the 2nd value is fully received or it will over-write the first in the buffer.

There is a 2 byte fifo buffer ...

Oops - missed that - thanks.
However it does mean that you need to read values before the FIFO fills up!
Susan

[vloki]

However it does mean that you need to read values before the FIFO fills up!

Yes, of course

@OP
This aspect will be the next step then.
The USART communication fortunately usually is sloooooowwwww
(lots of instructions can be executed while one byte is received)
There are lots of other things like overflow an framing errors already mentioned
by someone before ...