.S19 File Extension

Contains low-level machine code and addresses of a compiled C or Assembly program; saved in a text format that represents hexadecimal coded binary data; used by the Freescale series of microcontrollers.

Each line in an S19 file consists of one record. Every record begins with the letter "S," followed by a "1" if the record contains data or a "9" if it is the last record in the file.