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Looks for the next valid integer in the incoming serial. The function terminates if it times out (see Serial.setTimeout()).

Serial.parseInt() inherits from the Stream utility class.

In particular:

  • Parsing stops when no characters have been read for a configurable time-out value, or a non-digit is read;

  • If no valid digits were read when the time-out (see Serial.setTimeout()) occurs, 0 is returned;


Serial.parseInt(lookahead, ignore)


Serial: serial port object. See the list of available serial ports for each board on the Serial main page.
lookahead: the mode used to look ahead in the stream for an integer. Allowed data types: LookaheadMode. Allowed lookahead values:

  • SKIP_ALL: all characters other than digits or a minus sign are ignored when scanning the stream for an integer. This is the default mode.

  • SKIP_NONE: Nothing is skipped, and the stream is not touched unless the first waiting character is valid.

  • SKIP_WHITESPACE: Only tabs, spaces, line feeds, and carriage returns are skipped.

ignore: used to skip the indicated char in the search. Used for example to skip thousands divider. Allowed data types: char


The next valid integer. Data type: long.

See also