When an OCR string contains non-printable characters, the Match String can accept hexadecimal escape codes. These are of the form \xFF, where FF represents two hexadecimal digits. The "x" and the hex digits are not case sensitive.
To be processed, the escape sequence must be fully formed; otherwise it is treated as if it were not an escape sequence.
For example, to match ABCD<cr>EFG, where <cr> is a carriage return (hex 0D), set Match String to:
ABCD\x0DEFG
Using a serial command, this would be:
SET matchstring1 ABCD\x0DEFG