[merlincorey]

Consider instead that you do not have a prefix command, but you poll the line and there is data, so you retrieve it.

Now what do you do? Well, you check the first byte and see if it's a valid first byte for a command. There are hundreds of them, so basically every uppercase ASCII character should do.

In the happy path, you get a byte stream like "DT 1234\r\n".

Sometimes, the data stream has noise in it, so you get bytes like "%$DT 1234\r\n".

There are no commands that start with "%" or "$" so you can just drop it.

However, in the unhappy path, you might get bytes like "CMDT 1234\r\n".

CM is a valid command! But "DT 1234" are not valid arguments.

If only there was a way to get the ATtention of the parser before parsing commands...