Note: Checksum is a form of redundant test, which is used to check for any errors in the data.
5.6 Start Measurement Command with Checksum (aMC!)
This command is identical to the aM! command with the exception that a threecharacter checksum is returned before the <CR><LF> as part of the Send Data Command reply. The aMC1 to aMC9 commands are reserved for future use.