I need to syntax check incomming queries/commands on the UART and i would like some idears on how to do it. The syntax of the commands are as follow:
Syntax required for a query is: @<device address><query>?;FF
Syntax required for a command is: @<device address><command>!<parameter>;FF
Examples: Query current baud rate: @253BR?;FF Change baud rate to 19200: @253BR!19200;FF where: @ <attention character> 253 <device address> BR? <query> (for query syntax) BR!19200 <command>!<parameter> (for command syntax) ;FF <terminator>
Please note the termination is ;FF and not CR or LF.
Is it possible to use the scanf() function for this task? Something like this perhaps:
scanf("@%3s%2s?;FF", adr, command);
scanf() is for students. It has too many issue to be used in the real world.
use the other input functions (getch(), gets()) then parse the data your self. This allows you to verify the data is valid. scanf() may not like some data. It will then hang waiting for more data. Or, try to use the next peice on input.