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<h2>Serial.print(data)</h2>
<h4>Description</h4>
<p>Prints data to the serial port.
</p>
<p class='vspace'></p><h4>Parameter</h4>
<p>data: integer types, including char, floats<br />Printing of floats is supported with a precision of two places to the right of the decimal point.<br />This may change soon.
</p>
<p class='vspace'></p><h4>Syntax</h4>
<p>This command can take many forms:
</p>
<p class='vspace'></p><p><strong>Serial.print(b)</strong>
with no format specified, prints b as a decimal number in an ASCII string. For example,
</p>
<p class='vspace'></p><pre>
int b = 79;
Serial.print(b);
</pre><p>prints the ASCII string "79".
</p>
<p class='vspace'></p><p><strong>Serial.print(b, DEC)</strong>
prints b as a decimal number in an ASCII string. For example,
</p>
<p class='vspace'></p><pre>
int b = 79;
Serial.print(b, DEC);
</pre><p>prints the string "79".
</p>
<p class='vspace'></p><p><strong>Serial.print(b, HEX)</strong>
prints b as a hexadecimal number in an ASCII string. For example,
</p>
<p class='vspace'></p><pre>
int b = 79;
Serial.print(b, HEX);
</pre><p>prints the string "4F".
</p>
<p class='vspace'></p><p><strong>Serial.print(b, OCT)</strong>
prints b as an octal number in an ASCII string. For example,
</p>
<p class='vspace'></p><pre>
int b = 79;
Serial.print(b, OCT);
</pre><p>prints the string "117".
</p>
<p class='vspace'></p><p><strong>Serial.print(b, BIN)</strong>
prints b as a binary number in an ASCII string. For example,
</p>
<p class='vspace'></p><pre>
int b = 79;
Serial.print(b, BIN);
</pre><p>prints the string "1001111".
</p>
<p class='vspace'></p><p><strong>Serial.print(b, BYTE)</strong>
prints b as a single byte. For example,
</p>
<p class='vspace'></p><pre>
int b = 79;
Serial.print(b, BYTE);
</pre><p>returns the string "O", which is the ASCII character represented by the value 79. For more information see the <a class='urllink' href='http://www.asciitable.com' rel='nofollow'>ASCII table</a>.
</p>
<p class='vspace'></p><p><strong>Serial.print(str)</strong>
if str is a string or an array of chars, prints str as an ASCII string. For example,
</p>
<p class='vspace'></p><pre>
Serial.print("Hello World!");
</pre><p>prints the string "Hello World!".
</p>
<p class='vspace'></p><h4>Parameters</h4>
<p>b: the byte to print, or
</p>
<p class='vspace'></p><p>str: the string to print
</p>
<p class='vspace'></p><h4>Returns</h4>
<p>None
</p>
<p class='vspace'></p><h4>Example:</h4>
<pre>/*
Uses a FOR loop for data and prints a number in various formats.
*/
int x = 0; // variable
void setup() {
Serial.begin(9600); // open the serial port at 9600 bps:
}
void loop() {
// print labels
Serial.print("NO FORMAT"); // prints a label
Serial.print("\t"); // prints a tab
Serial.print("DEC");
Serial.print("\t");
Serial.print("HEX");
Serial.print("\t");
Serial.print("OCT");
Serial.print("\t");
Serial.print("BIN");
Serial.print("\t");
Serial.println("BYTE");
for(x=0; x< 64; x++){ // only part of the ASCII chart, change to suit
// print it out in many formats:
Serial.print(x); // print as an ASCII-encoded decimal - same as "DEC"
Serial.print("\t"); // prints a tab
Serial.print(x, DEC); // print as an ASCII-encoded decimal
Serial.print("\t"); // prints a tab
Serial.print(x, HEX); // print as an ASCII-encoded hexadecimal
Serial.print("\t"); // prints a tab
Serial.print(x, OCT); // print as an ASCII-encoded octal
Serial.print("\t"); // prints a tab
Serial.print(x, BIN); // print as an ASCII-encoded binary
Serial.print("\t"); // prints a tab
Serial.println(x, BYTE); // prints as a raw byte value,
// then adds the carriage return with "println"
delay(200); // delay 200 milliseconds
}
Serial.println(""); // prints another carriage return
}
</pre>
<p class='vspace'></p><h4>Programming Tips / Known Issues</h4>
<p>Serial.print() doesn't work on floats, so you'll need to cast them to an integral type, losing any fractional values. It is sometimes useful to multiply your float by a power of ten, to preserve some of this fractional resolution.
</p>
<p class='vspace'></p><p>Be careful about doing math inside the brackets e.g.<br /><code>Serial.print(x-2, DEC);</code><br />The unsigned char data type, and byte data type will yield incorrect results and act as though they are signed types i.e. type char.
</p>
<p class='vspace'></p><p>The Serial.print function puts data into a buffer. It will wait for one character to send, before going on to the next character. However the function returns before sending the <em>last</em> character.
</p>
<p class='vspace'></p><h4>See also</h4>
<ul><li><a class='wikilink' href='ASCIIchart.html'>ASCII chart</a>
</li><li><a class='wikilink' href='Serial_Begin.html'>Serial.begin</a>(speed)
</li><li><a class='wikilink' href='Serial_Available.html'>Serial.available</a>()
</li><li><a class='wikilink' href='Serial_Read.html'>Serial.read</a>()
</li><li><a class='wikilink' href='Serial_Println.html'>Serial.println</a>(data)
</li></ul><p class='vspace'></p><p><a class='wikilink' href='index.html'>Reference Home</a>
</p>
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