Serial.print()
Description
Prints data to the serial port as human-readable ASCII text. This command can take many forms. Numbers are printed using an ASCII character for each digit. Floats are similarly printed as ASCII digits, defaulting to two decimal places. Bytes are sent as a single character. Characters and strings are sent as is. For example-
gives "78"Serial.print(78)
gives "1.23"Serial.print(1.23456)
gives "N"Serial.print('N')
gives "Hello world."Serial.print("Hello world.")
An optional second parameter specifies the base (format) to use; permitted values are
BIN(binary, or base 2)
, OCT(octal, or base 8)
, DEC(decimal, or base 10)
, HEX(hexadecimal, or base 16)
. For floating point numbers, this parameter specifies the number of decimal places to use. For example:
gives "1001110"Serial.print(78, BIN)
gives "116"Serial.print(78, OCT)
gives "78"Serial.print(78, DEC)
gives "4E"Serial.print(78, HEX)
gives "1"Serial.print(1.23456, 0)
gives "1.23"Serial.print(1.23456, 2)
gives "1.2346"Serial.print(1.23456, 4)
You can pass flash-memory based strings to
Serial.print()
by wrapping them with F(). For example:Serial.print(F("Hello World"))
To send data without conversion to its representation as characters, use Serial.write().
Syntax
Serial.print(val)
Serial.print(val, format)
Parameters
Serial
: serial port object. See the list of available serial ports for each board on the Serial main page.val
: the value to print. Allowed data types: any data type.Returns
print()
returns the number of bytes written, though reading that number is optional. Data type: size_t
.Example Code
1/*2 Uses a for loop to print numbers in various formats.3 */4 void setup() {5 Serial.begin(9600); // open the serial port at 9600 bps:6 }7
8 void loop() {9 // print labels10 Serial.print("NO FORMAT"); // prints a label11 Serial.print("\t"); // prints a tab12
13 Serial.print("DEC");14 Serial.print("\t");15
16 Serial.print("HEX");17 Serial.print("\t");18
19 Serial.print("OCT");20 Serial.print("\t");21
22 Serial.print("BIN");23 Serial.println(); // carriage return after the last label24
25 for (int x = 0; x < 64; x++) { // only part of the ASCII chart, change to suit26 // print it out in many formats:27 Serial.print(x); // print as an ASCII-encoded decimal - same as "DEC"28 Serial.print("\t\t"); // prints two tabs to accomodate the label length29
30 Serial.print(x, DEC); // print as an ASCII-encoded decimal31 Serial.print("\t"); // prints a tab32
33 Serial.print(x, HEX); // print as an ASCII-encoded hexadecimal34 Serial.print("\t"); // prints a tab35
36 Serial.print(x, OCT); // print as an ASCII-encoded octal37 Serial.print("\t"); // prints a tab38
39 Serial.println(x, BIN); // print as an ASCII-encoded binary40 // then adds the carriage return with "println"41 delay(200); // delay 200 milliseconds42 }43 Serial.println(); // prints another carriage return44 }
Notes and Warnings
For information on the asyncronicity of
Serial.print()
, see the Notes and Warnings section of the Serial.write() reference page.See also
Suggest changes
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License
The Arduino documentation is licensed under the Creative Commons Attribution-Share Alike 4.0 license.