Grouped Clickable Topic Index
The index intentionally lists titles only. Click any title to jump directly to the typed details for that topic.
Functions 114
Advanced I/O 6
Analog I/O 5
Bits and Bytes 7
Characters 13
Communication 42
- if (Serial)
- print()
- Serial
- Serial.available()
- Serial.parseFloat()
- Serial.print()
- Serial.println()
- Serial.read()
- Serial.readBytes()
- Serial.readBytesUntil()
- Serial.readStringUntil()
- Serial.write()
- SPI
- SPI.begin()
- SPI.beginTransaction()
- SPI.end()
- SPI.endTransaction()
- SPI.setBitOrder()
- SPI.setClockDivider()
- SPI.setDataMode()
- SPI.transfer()
- SPI.usingInterrupt()
- Stream
- Stream.available()
- Stream.find()
- Stream.findUntil()
- Stream.flush()
- Stream.parseFloat()
- Stream.parseInt()
- Stream.peek()
- Stream.read()
- Stream.readBytes()
- Stream.readBytesUntil()
- Stream.readString()
- Stream.readStringUntil()
- Stream.setTimeout()
- Wire
- Wire.begin()
- Wire.beginTransmission()
- Wire.end()
- Wire.getWireTimeoutFlag()
- Wire.onReceive()
Digital I/O 3
External Interrupts 3
Interrupts 2
Random Numbers 2
Time 3
USB 11
Structure 26
Arithmetic Operators 5
Bitwise Operators 4
Comparison Operators 2
Compound Operators 5
Control Structure 4
Further Syntax 2
Pointer Access Operators 2
Variables 56
Conversion 5
Data Types 46
- bool
- byte
- char
- float
- int
- long
- short
- size_t
- string
- String
- String append operator
- String comparison operators
- String concatenation operator
- String different-from operator
- String element access operator
- String greater-than operator
- String greater-than-or-equal-to operator
- String less-than operator
- String less-than-or-equal-to operator
- String.c_str()
- String.charAt()
- String.compareTo()
- String.concat()
- String.endsWith()
- String.equals()
- String.equalsIgnoreCase()
- String.getBytes()
- String.indexOf()
- String.lastIndexOf()
- String.length()
- String.remove()
- String.replace()
- String.reserve()
- String.setCharAt()
- String.startsWith()
- String.substring()
- String.toCharArray()
- String.toDouble()
- String.toFloat()
- String.toInt()
- String.toLowerCase()
- String.toUpperCase()
- String.trim()
- unsigned char
- unsigned int
- word
Detailed Topic Sections
Functions / Advanced I/O
noTone()
Description
Stops a square-wave tone that was previously started with tone(). If no tone is active on that pin, it has no effect.
Syntax / common form
noTone(pin);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Timing-sensitive functions may be affected by interrupts, board speed, and hardware capabilities.
Functions / Advanced I/O
pulseIn()
Description
Measures how long a pin stays HIGH or LOW and returns the pulse duration in microseconds.
Syntax / common form
pulseIn(pin, value);
pulseIn(pin, value, timeout);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Returns a value. The exact type depends on the function.
Notes
Timing-sensitive functions may be affected by interrupts, board speed, and hardware capabilities.
Functions / Advanced I/O
pulseInLong()
Description
Measures longer pulse durations in microseconds and is used when pulseIn() is not the best fit for a longer signal.
Syntax / common form
pulseInLong(pin, value);
pulseInLong(pin, value, timeout);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Returns a value. The exact type depends on the function.
Notes
Timing-sensitive functions may be affected by interrupts, board speed, and hardware capabilities.
Functions / Advanced I/O
shiftIn()
Description
Reads one byte of data one bit at a time from a data pin using a clock pin.
Syntax / common form
byte value = shiftIn(dataPin, clockPin, bitOrder);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Timing-sensitive functions may be affected by interrupts, board speed, and hardware capabilities.
Functions / Advanced I/O
shiftOut()
Description
Writes one byte of data one bit at a time to a data pin using a clock pin.
Syntax / common form
shiftOut(dataPin, clockPin, bitOrder, value);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Timing-sensitive functions may be affected by interrupts, board speed, and hardware capabilities.
Functions / Advanced I/O
tone()
Description
Generates a square wave on a pin at a specified frequency, often used for buzzers or simple audio output.
Syntax / common form
tone(pin, frequency);
tone(pin, frequency, duration);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Timing-sensitive functions may be affected by interrupts, board speed, and hardware capabilities.
Functions / Analog I/O
analogRead()
Description
Reads the value from an analog input pin and converts it to a digital number.
Syntax / common form
int value = analogRead(pin);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Returns a value. The exact type depends on the function.
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Functions / Analog I/O
analogReadResolution()
Description
Sets the number of bits used when reading analog values on boards that support adjustable ADC resolution.
Syntax / common form
analogReadResolution(bits);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Returns a value. The exact type depends on the function.
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Functions / Analog I/O
analogReference()
Description
Configures the reference voltage used for analog input readings on supported boards.
Syntax / common form
analogReference(type);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Functions / Analog I/O
analogWrite()
Description
Writes a PWM value, or a true analog value on supported boards, to an output pin.
Syntax / common form
analogWrite(pin, value);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Functions / Analog I/O
analogWriteResolution()
Description
Sets the number of bits used when writing analog or PWM values on boards that support adjustable output resolution.
Syntax / common form
analogWriteResolution(bits);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Functions / Bits and Bytes
bit()
Description
Reference entry for bit() in the Arduino Bits and Bytes group.
Syntax / common form
bit(n);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Returns a value. The exact type depends on the function.
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Functions / Bits and Bytes
bitClear()
Description
Reference entry for bitClear() in the Arduino Bits and Bytes group.
Syntax / common form
bitClear(x, n);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Functions / Bits and Bytes
bitRead()
Description
Reads the next byte or character from the input buffer.
Syntax / common form
bitRead(x, n);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Returns a value. The exact type depends on the function.
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Functions / Bits and Bytes
bitSet()
Description
Reference entry for bitSet() in the Arduino Bits and Bytes group.
Syntax / common form
bitSet(x, n);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Functions / Bits and Bytes
bitWrite()
Description
Writes binary data to the output stream.
Syntax / common form
bitWrite(x, n, b);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Functions / Bits and Bytes
highByte()
Description
Reference entry for highByte() in the Arduino Bits and Bytes group.
Syntax / common form
highByte(x);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Returns a value. The exact type depends on the function.
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Functions / Bits and Bytes
lowByte()
Description
Reference entry for lowByte() in the Arduino Bits and Bytes group.
Syntax / common form
lowByte(x);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Returns a value. The exact type depends on the function.
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Functions / Characters
isAlpha()
Description
Tests whether a character is alphabetic.
Syntax / common form
// Syntax varies by use case for isAlpha()Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Functions / Characters
isAlphaNumeric()
Description
Tests whether a character is a letter or number.
Syntax / common form
// Syntax varies by use case for isAlphaNumeric()Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Functions / Characters
isAscii()
Description
Tests whether a character is within the ASCII range.
Syntax / common form
// Syntax varies by use case for isAscii()Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Functions / Characters
isControl()
Description
Tests whether a character is a control character.
Syntax / common form
// Syntax varies by use case for isControl()Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Functions / Characters
isDigit()
Description
Tests whether a character is a decimal digit.
Syntax / common form
// Syntax varies by use case for isDigit()Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Functions / Characters
isGraph()
Description
Tests whether a character has a visible representation other than a space.
Syntax / common form
// Syntax varies by use case for isGraph()Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Functions / Characters
isHexadecimalDigit()
Description
Tests whether a character is a valid hexadecimal digit.
Syntax / common form
// Syntax varies by use case for isHexadecimalDigit()Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Functions / Characters
isLowerCase()
Description
Tests whether a character is lowercase.
Syntax / common form
// Syntax varies by use case for isLowerCase()Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Functions / Characters
isPrintable()
Description
Tests whether a character is printable.
Syntax / common form
// Syntax varies by use case for isPrintable()Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Functions / Characters
isPunct()
Description
Tests whether a character is punctuation.
Syntax / common form
// Syntax varies by use case for isPunct()Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Functions / Characters
isSpace()
Description
Tests whether a character is a whitespace/spacing character.
Syntax / common form
// Syntax varies by use case for isSpace()Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Functions / Characters
isUpperCase()
Description
Tests whether a character is uppercase.
Syntax / common form
// Syntax varies by use case for isUpperCase()Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Functions / Characters
isWhitespace()
Description
Tests whether a character is whitespace.
Syntax / common form
// Syntax varies by use case for isWhitespace()Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Functions / Communication
if (Serial)
Description
Reference entry for if (Serial) in the Arduino Communication group.
Syntax / common form
if (Serial) { /* USB serial is ready */ }Parameters / values
Not a callable function; see related methods or examples for the object/class.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / Communication
print()
Description
Prints data in human-readable text form.
Syntax / common form
// Syntax varies by use case for print()Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / Communication
Serial
Description
Represents the serial communication interface used to send and receive data over USB or UART, depending on the board.
Syntax / common form
// See methods in the Serial reference group.Parameters / values
Not a callable function; see related methods or examples for the object/class.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / Communication
Serial.available()
Description
Returns how many bytes are available to read without blocking.
Syntax / common form
int count = Serial.available();Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Returns a value. The exact type depends on the function.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / Communication
Serial.parseFloat()
Description
Reads characters from a stream and converts them into a floating-point value.
Syntax / common form
float value = Serial.parseFloat();Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Returns a value. The exact type depends on the function.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / Communication
Serial.print()
Description
Prints data in human-readable text form.
Syntax / common form
Serial.print(value);
Serial.print(value, format);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / Communication
Serial.println()
Description
Prints data followed by a newline.
Syntax / common form
Serial.println(value);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / Communication
Serial.read()
Description
Reads the next byte or character from the input buffer.
Syntax / common form
int byteValue = Serial.read();Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Returns a value. The exact type depends on the function.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / Communication
Serial.readBytes()
Description
Reads multiple bytes into a buffer.
Syntax / common form
Serial.readBytes(buffer, length);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Returns a value. The exact type depends on the function.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / Communication
Serial.readBytesUntil()
Description
Reads bytes into a buffer until a terminator character or length limit is reached.
Syntax / common form
Serial.readBytesUntil(character, buffer, length);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Returns a value. The exact type depends on the function.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / Communication
Serial.readStringUntil()
Description
Reads characters into a String until a terminator is found or timeout occurs.
Syntax / common form
String s = Serial.readStringUntil(terminator);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Returns a value. The exact type depends on the function.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / Communication
Serial.write()
Description
Writes binary data to the output stream.
Syntax / common form
Serial.write(value);
Serial.write(buffer, length);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / Communication
SPI
Description
Represents the SPI bus used for fast synchronous communication with peripherals.
Syntax / common form
// See methods in the SPI reference group.Parameters / values
Not a callable function; see related methods or examples for the object/class.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / Communication
SPI.begin()
Description
Starts or initializes the interface.
Syntax / common form
SPI.begin();Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / Communication
SPI.beginTransaction()
Description
Starts an SPI transaction using a selected settings object.
Syntax / common form
SPI.beginTransaction(settings);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / Communication
SPI.end()
Description
Stops or shuts down the interface.
Syntax / common form
SPI.end();Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / Communication
SPI.endTransaction()
Description
Ends the active SPI transaction.
Syntax / common form
SPI.endTransaction();Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / Communication
SPI.setBitOrder()
Description
Sets whether SPI data is shifted most-significant-bit first or least-significant-bit first.
Syntax / common form
SPI.setBitOrder(order);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / Communication
SPI.setClockDivider()
Description
Sets the SPI clock divider on older SPI APIs.
Syntax / common form
SPI.setClockDivider(divider);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / Communication
SPI.setDataMode()
Description
Sets the SPI clock polarity and phase mode.
Syntax / common form
SPI.setDataMode(mode);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / Communication
SPI.transfer()
Description
Transfers data over SPI while simultaneously receiving data.
Syntax / common form
byte result = SPI.transfer(value);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / Communication
SPI.usingInterrupt()
Description
Informs the SPI library that an interrupt may use SPI so transactions can be protected.
Syntax / common form
SPI.usingInterrupt(interruptNumber);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Returns a value. The exact type depends on the function.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / Communication
Stream
Description
Base class for stream-like input/output objects such as Serial, Ethernet clients, and file streams.
Syntax / common form
// See methods in the Stream reference group.Parameters / values
Not a callable function; see related methods or examples for the object/class.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / Communication
Stream.available()
Description
Returns how many bytes are available to read without blocking.
Syntax / common form
int count = stream.available();Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Returns a value. The exact type depends on the function.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / Communication
Stream.find()
Description
Searches a stream for a target sequence.
Syntax / common form
bool found = stream.find(target);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Returns a value. The exact type depends on the function.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / Communication
Stream.findUntil()
Description
Searches a stream for a target sequence until a terminator is found.
Syntax / common form
bool found = stream.findUntil(target, terminator);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Returns a value. The exact type depends on the function.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / Communication
Stream.flush()
Description
Waits for outgoing data to finish or clears/handles buffered data depending on the stream implementation.
Syntax / common form
stream.flush();Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / Communication
Stream.parseFloat()
Description
Reads characters from a stream and converts them into a floating-point value.
Syntax / common form
float value = stream.parseFloat();Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Returns a value. The exact type depends on the function.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / Communication
Stream.parseInt()
Description
Reads characters from a stream and converts them into an integer value.
Syntax / common form
long value = stream.parseInt();Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Returns a value. The exact type depends on the function.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / Communication
Stream.peek()
Description
Returns the next byte without removing it from the input buffer.
Syntax / common form
int value = stream.peek();Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Returns a value. The exact type depends on the function.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / Communication
Stream.read()
Description
Reads the next byte or character from the input buffer.
Syntax / common form
int value = stream.read();Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Returns a value. The exact type depends on the function.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / Communication
Stream.readBytes()
Description
Reads multiple bytes into a buffer.
Syntax / common form
stream.readBytes(buffer, length);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Returns a value. The exact type depends on the function.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / Communication
Stream.readBytesUntil()
Description
Reads bytes into a buffer until a terminator character or length limit is reached.
Syntax / common form
stream.readBytesUntil(character, buffer, length);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Returns a value. The exact type depends on the function.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / Communication
Stream.readString()
Description
Reads characters from a stream into a String until timeout.
Syntax / common form
String s = stream.readString();Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Returns a value. The exact type depends on the function.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / Communication
Stream.readStringUntil()
Description
Reads characters into a String until a terminator is found or timeout occurs.
Syntax / common form
String s = stream.readStringUntil(terminator);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Returns a value. The exact type depends on the function.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / Communication
Stream.setTimeout()
Description
Sets how long stream parsing/read functions wait before timing out.
Syntax / common form
stream.setTimeout(milliseconds);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / Communication
Wire
Description
Arduino I2C/TWI library interface used to communicate with I2C devices.
Syntax / common form
// See methods in the Wire reference group.Parameters / values
Not a callable function; see related methods or examples for the object/class.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / Communication
Wire.begin()
Description
Starts or initializes the interface.
Syntax / common form
Wire.begin();
Wire.begin(address);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / Communication
Wire.beginTransmission()
Description
Begins an I2C transmission to a device address.
Syntax / common form
Wire.beginTransmission(address);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / Communication
Wire.end()
Description
Stops or shuts down the interface.
Syntax / common form
Wire.end();Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / Communication
Wire.getWireTimeoutFlag()
Description
Checks whether the I2C/Wire interface has detected a timeout condition.
Syntax / common form
bool flag = Wire.getWireTimeoutFlag();Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Returns a value. The exact type depends on the function.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / Communication
Wire.onReceive()
Description
Registers a handler function that runs when I2C data is received.
Syntax / common form
Wire.onReceive(handler);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / Digital I/O
digitalRead()
Description
Reads whether a digital pin is HIGH or LOW.
Syntax / common form
int state = digitalRead(pin);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Returns a value. The exact type depends on the function.
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Functions / Digital I/O
digitalWrite()
Description
Writes HIGH or LOW to a digital output pin, or enables/disables pull-up behavior on an input pin.
Syntax / common form
digitalWrite(pin, value);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Functions / Digital I/O
pinMode()
Description
Configures a pin as an input, input with pull-up resistor, or output.
Syntax / common form
pinMode(pin, mode);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Functions / External Interrupts
attachInterrupt()
Description
Attaches an interrupt service routine to a hardware interrupt so code can react quickly to pin changes.
Syntax / common form
attachInterrupt(digitalPinToInterrupt(pin), ISR, mode);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Timing-sensitive functions may be affected by interrupts, board speed, and hardware capabilities.
Functions / External Interrupts
detachInterrupt()
Description
Removes a previously attached interrupt handler.
Syntax / common form
detachInterrupt(digitalPinToInterrupt(pin));Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Timing-sensitive functions may be affected by interrupts, board speed, and hardware capabilities.
Functions / External Interrupts
digitalPinToInterrupt()
Description
Converts a board pin number into the interrupt number expected by attachInterrupt().
Syntax / common form
digitalPinToInterrupt(pin);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Returns a value. The exact type depends on the function.
Notes
Timing-sensitive functions may be affected by interrupts, board speed, and hardware capabilities.
Functions / Interrupts
interrupts()
Description
Re-enables interrupts after they were disabled.
Syntax / common form
interrupts();Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Timing-sensitive functions may be affected by interrupts, board speed, and hardware capabilities.
Functions / Interrupts
noInterrupts()
Description
Temporarily disables interrupts for timing-sensitive critical sections.
Syntax / common form
noInterrupts();Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Timing-sensitive functions may be affected by interrupts, board speed, and hardware capabilities.
Functions / Math
abs()
Description
Returns the absolute value of a number.
Syntax / common form
abs(x);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Returns a value. The exact type depends on the function.
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Functions / Math
constrain()
Description
Restricts a value so it stays between a lower and upper bound.
Syntax / common form
constrain(x, a, b);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Functions / Math
map()
Description
Re-maps a number from one numeric range into another.
Syntax / common form
map(value, fromLow, fromHigh, toLow, toHigh);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Returns a value. The exact type depends on the function.
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Functions / Math
max()
Description
Returns the larger of two values.
Syntax / common form
max(x, y);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Returns a value. The exact type depends on the function.
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Functions / Math
min()
Description
Returns the smaller of two values.
Syntax / common form
min(x, y);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Returns a value. The exact type depends on the function.
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Functions / Math
pow()
Description
Raises a number to a power.
Syntax / common form
pow(base, exponent);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Returns a value. The exact type depends on the function.
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Functions / Math
sq()
Description
Returns the square of a value.
Syntax / common form
sq(x);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Returns a value. The exact type depends on the function.
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Functions / Math
sqrt()
Description
Returns the square root of a value.
Syntax / common form
sqrt(x);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Returns a value. The exact type depends on the function.
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Functions / Random Numbers
random()
Description
Returns a pseudo-random number in a specified range.
Syntax / common form
random(max);
random(min, max);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Returns a value. The exact type depends on the function.
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Functions / Random Numbers
randomSeed()
Description
Initializes the pseudo-random number generator with a seed value.
Syntax / common form
randomSeed(seed);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Returns a value. The exact type depends on the function.
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Functions / Time
delay()
Description
Pauses the sketch for a specified number of milliseconds.
Syntax / common form
delay(ms);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Timing-sensitive functions may be affected by interrupts, board speed, and hardware capabilities.
Functions / Time
delayMicroseconds()
Description
Pauses the sketch for a specified number of microseconds.
Syntax / common form
delayMicroseconds(us);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Returns a value. The exact type depends on the function.
Notes
Timing-sensitive functions may be affected by interrupts, board speed, and hardware capabilities.
Functions / Time
micros()
Description
Returns the number of microseconds since the board began running the current program.
Syntax / common form
unsigned long now = micros();Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Returns a value. The exact type depends on the function.
Notes
Timing-sensitive functions may be affected by interrupts, board speed, and hardware capabilities.
Functions / Trigonometry
cos()
Description
Returns the cosine of an angle in radians.
Syntax / common form
cos(rad);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Returns a value. The exact type depends on the function.
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Functions / Trigonometry
sin()
Description
Returns the sine of an angle in radians.
Syntax / common form
sin(rad);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Returns a value. The exact type depends on the function.
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Functions / Trigonometry
tan()
Description
Returns the tangent of an angle in radians.
Syntax / common form
tan(rad);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Returns a value. The exact type depends on the function.
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Functions / USB
Keyboard
Description
USB HID keyboard interface for supported boards that can emulate keyboard input.
Syntax / common form
// See methods in the Keyboard reference group.Parameters / values
Not a callable function; see related methods or examples for the object/class.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / USB
Keyboard Modifiers
Description
Reference entry for Keyboard Modifiers in the Arduino USB group.
Syntax / common form
// Syntax varies by use case for Keyboard ModifiersParameters / values
Not a callable function; see related methods or examples for the object/class.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / USB
Keyboard.end()
Description
Stops or shuts down the interface.
Syntax / common form
Keyboard.end();Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / USB
Keyboard.press()
Description
Reference entry for Keyboard.press() in the Arduino USB group.
Syntax / common form
Keyboard.press(key);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / USB
Keyboard.print()
Description
Prints data in human-readable text form.
Syntax / common form
Keyboard.print(value);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / USB
Keyboard.println()
Description
Prints data followed by a newline.
Syntax / common form
Keyboard.println(value);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / USB
Keyboard.release()
Description
Reference entry for Keyboard.release() in the Arduino USB group.
Syntax / common form
Keyboard.release(key);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / USB
Keyboard.releaseAll()
Description
Reference entry for Keyboard.releaseAll() in the Arduino USB group.
Syntax / common form
Keyboard.releaseAll();Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / USB
Mouse
Description
USB HID mouse interface for supported boards that can emulate mouse input.
Syntax / common form
// See methods in the Mouse reference group.Parameters / values
Not a callable function; see related methods or examples for the object/class.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / USB
Mouse.begin()
Description
Starts or initializes the interface.
Syntax / common form
Mouse.begin();Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / USB
Mouse.release()
Description
Reference entry for Mouse.release() in the Arduino USB group.
Syntax / common form
Mouse.release(button);Parameters / values
Common parameters include pins, values, buffers, counts, strings, addresses, modes, or timeouts depending on the function.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / WiFi
Client
Description
Base client networking interface for TCP-style connections.
Syntax / common form
// See methods in the Client reference group.Parameters / values
Not a callable function; see related methods or examples for the object/class.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / WiFi
IPAddress
Description
Represents an IPv4 address used with networking functions.
Syntax / common form
// See methods in the IPAddress reference group.Parameters / values
Not a callable function; see related methods or examples for the object/class.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / WiFi
Overview
Description
General overview entry for the WiFi reference group.
Syntax / common form
// See methods in the Overview reference group.Parameters / values
Not a callable function; see related methods or examples for the object/class.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / WiFi
Server
Description
Base server networking interface for listening for incoming clients.
Syntax / common form
// See methods in the Server reference group.Parameters / values
Not a callable function; see related methods or examples for the object/class.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / WiFi
UDP
Description
Interface for sending and receiving UDP datagrams.
Syntax / common form
// See methods in the UDP reference group.Parameters / values
Not a callable function; see related methods or examples for the object/class.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Functions / WiFi
WiFiClass
Description
Main WiFi control class used by WiFi-capable Arduino boards or WiFi libraries.
Syntax / common form
// See methods in the WiFiClass reference group.Parameters / values
Not a callable function; see related methods or examples for the object/class.
Returns / result
Usually returns nothing unless the specific method is documented otherwise.
Notes
Board/library support can vary. Confirm the target board supports this interface before relying on it.
Structure / Arithmetic Operators
Addition: +
Description
Adds two values.
Syntax / common form
result = a + b;Parameters / values
Conditions, expressions, operands, or code blocks depending on the language feature.
Returns / result
Not applicable as a standalone return value.
Notes
Operator precedence can affect results. Use parentheses when code clarity matters.
Structure / Arithmetic Operators
Division: /
Description
Divides the left value by the right value.
Syntax / common form
result = a / b;Parameters / values
Conditions, expressions, operands, or code blocks depending on the language feature.
Returns / result
Not applicable as a standalone return value.
Notes
Operator precedence can affect results. Use parentheses when code clarity matters.
Structure / Arithmetic Operators
Multiplication: *
Description
Multiplies two values.
Syntax / common form
result = a * b;Parameters / values
Conditions, expressions, operands, or code blocks depending on the language feature.
Returns / result
Not applicable as a standalone return value.
Notes
Operator precedence can affect results. Use parentheses when code clarity matters.
Structure / Arithmetic Operators
Remainder: %
Description
Returns the remainder after integer division.
Syntax / common form
result = a % b;Parameters / values
Conditions, expressions, operands, or code blocks depending on the language feature.
Returns / result
Not applicable as a standalone return value.
Notes
Operator precedence can affect results. Use parentheses when code clarity matters.
Structure / Arithmetic Operators
Subtraction: –
Description
Subtracts the right value from the left value.
Syntax / common form
result = a - b;Parameters / values
Conditions, expressions, operands, or code blocks depending on the language feature.
Returns / result
Not applicable as a standalone return value.
Notes
Operator precedence can affect results. Use parentheses when code clarity matters.
Structure / Bitwise Operators
Bitshift Left: <<
Description
Shifts bits left by a selected number of positions.
Syntax / common form
result = a << b;Parameters / values
Conditions, expressions, operands, or code blocks depending on the language feature.
Returns / result
Not applicable as a standalone return value.
Notes
Operator precedence can affect results. Use parentheses when code clarity matters.
Structure / Bitwise Operators
Bitwise NOT: ~
Description
Inverts every bit in a value.
Syntax / common form
result = a ~ b;Parameters / values
Conditions, expressions, operands, or code blocks depending on the language feature.
Returns / result
Not applicable as a standalone return value.
Notes
Operator precedence can affect results. Use parentheses when code clarity matters.
Structure / Bitwise Operators
Bitwise OR: |
Description
Sets each result bit when either input bit is 1.
Syntax / common form
result = a | b;Parameters / values
Conditions, expressions, operands, or code blocks depending on the language feature.
Returns / result
Not applicable as a standalone return value.
Notes
Operator precedence can affect results. Use parentheses when code clarity matters.
Structure / Bitwise Operators
Bitwise XOR: ^
Description
Sets each result bit when the input bits differ.
Syntax / common form
result = a ^ b;Parameters / values
Conditions, expressions, operands, or code blocks depending on the language feature.
Returns / result
Not applicable as a standalone return value.
Notes
Operator precedence can affect results. Use parentheses when code clarity matters.
Structure / Comparison Operators
Less Than or Equal To: <=
Description
Tests whether the left value is less than or equal to the right value.
Syntax / common form
if (a <= b) {
// code
}Parameters / values
Conditions, expressions, operands, or code blocks depending on the language feature.
Returns / result
Not applicable as a standalone return value.
Notes
Operator precedence can affect results. Use parentheses when code clarity matters.
Structure / Comparison Operators
Less Than: <
Description
Tests whether the left value is less than the right value.
Syntax / common form
if (a < b) {
// code
}Parameters / values
Conditions, expressions, operands, or code blocks depending on the language feature.
Returns / result
Not applicable as a standalone return value.
Notes
Operator precedence can affect results. Use parentheses when code clarity matters.
Structure / Compound Operators
Compound Bitwise XOR: ^=
Description
Applies bitwise XOR and stores the result back into the variable.
Syntax / common form
x ^= value;Parameters / values
Conditions, expressions, operands, or code blocks depending on the language feature.
Returns / result
Not applicable as a standalone return value.
Notes
Operator precedence can affect results. Use parentheses when code clarity matters.
Structure / Compound Operators
Compound Multiplication: *=
Description
Multiplies a variable by a value and stores the result back into the variable.
Syntax / common form
x *= value;Parameters / values
Conditions, expressions, operands, or code blocks depending on the language feature.
Returns / result
Not applicable as a standalone return value.
Notes
Operator precedence can affect results. Use parentheses when code clarity matters.
Structure / Compound Operators
Compound Subtraction: -=
Description
Subtracts a value from a variable and stores the result back into the variable.
Syntax / common form
x -= value;Parameters / values
Conditions, expressions, operands, or code blocks depending on the language feature.
Returns / result
Not applicable as a standalone return value.
Notes
Operator precedence can affect results. Use parentheses when code clarity matters.
Structure / Compound Operators
Decrement: —
Description
Decreases a variable by one.
Syntax / common form
x--;
--x;Parameters / values
Conditions, expressions, operands, or code blocks depending on the language feature.
Returns / result
Not applicable as a standalone return value.
Notes
Operator precedence can affect results. Use parentheses when code clarity matters.
Structure / Compound Operators
Increment: ++
Description
Increases a variable by one.
Syntax / common form
x++;
++x;Parameters / values
Conditions, expressions, operands, or code blocks depending on the language feature.
Returns / result
Not applicable as a standalone return value.
Notes
Operator precedence can affect results. Use parentheses when code clarity matters.
Structure / Control Structure
else
Description
Runs an alternate block of code when an if condition is false.
Syntax / common form
if (condition) {
// code
} else {
// alternate code
}Parameters / values
Conditions, expressions, operands, or code blocks depending on the language feature.
Returns / result
Not applicable as a standalone return value.
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Structure / Control Structure
if
Description
Runs a block of code only when a condition is true.
Syntax / common form
if (condition) {
// code
}Parameters / values
Conditions, expressions, operands, or code blocks depending on the language feature.
Returns / result
Not applicable as a standalone return value.
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Structure / Control Structure
switch…case
Description
Chooses between multiple code paths based on a matching value.
Syntax / common form
switch (value) {
case 1:
// code
break;
default:
// code
break;
}Parameters / values
Conditions, expressions, operands, or code blocks depending on the language feature.
Returns / result
Not applicable as a standalone return value.
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Structure / Control Structure
while
Description
Repeats a block of code while a condition remains true.
Syntax / common form
while (condition) {
// repeated code
}Parameters / values
Conditions, expressions, operands, or code blocks depending on the language feature.
Returns / result
Not applicable as a standalone return value.
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Structure / Further Syntax
Block Comment: /* */
Description
Creates a multi-line comment ignored by the compiler.
Syntax / common form
/*
comment text
*/Parameters / values
Conditions, expressions, operands, or code blocks depending on the language feature.
Returns / result
Not applicable as a standalone return value.
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Structure / Further Syntax
Curly Braces: { }
Description
Groups statements into a block for functions, conditions, loops, and classes.
Syntax / common form
functionName() {
// block
}Parameters / values
Conditions, expressions, operands, or code blocks depending on the language feature.
Returns / result
Not applicable as a standalone return value.
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Structure / Pointer Access Operators
Dereference Operator: *
Description
Accesses the value stored at a pointer address.
Syntax / common form
// Pointer syntax depends on declaration and use context.Parameters / values
Conditions, expressions, operands, or code blocks depending on the language feature.
Returns / result
Not applicable as a standalone return value.
Notes
Operator precedence can affect results. Use parentheses when code clarity matters.
Structure / Pointer Access Operators
Reference Operator: &
Description
Gets the memory address of a variable.
Syntax / common form
// Pointer syntax depends on declaration and use context.Parameters / values
Conditions, expressions, operands, or code blocks depending on the language feature.
Returns / result
Not applicable as a standalone return value.
Notes
Operator precedence can affect results. Use parentheses when code clarity matters.
Structure / Sketch
loop()
Description
Special Arduino function that runs repeatedly after setup() finishes.
Syntax / common form
void loop() {
// repeats forever
}Parameters / values
Conditions, expressions, operands, or code blocks depending on the language feature.
Returns / result
Not applicable as a standalone return value.
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Structure / Sketch
setup()
Description
Special Arduino function that runs once when the sketch starts.
Syntax / common form
void setup() {
// runs once
}Parameters / values
Conditions, expressions, operands, or code blocks depending on the language feature.
Returns / result
Not applicable as a standalone return value.
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Variables / Conversion
char()
Description
Casts or converts a value to char.
Syntax / common form
char(value);Parameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Variables / Conversion
long()
Description
Casts or converts a value to long.
Syntax / common form
long(value);Parameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Variables / Conversion
unsigned int()
Description
Casts or converts a value to unsigned int.
Syntax / common form
unsigned int(value);Parameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Variables / Conversion
unsigned long()
Description
Casts or converts a value to unsigned long.
Syntax / common form
unsigned long(value);Parameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Variables / Conversion
word()
Description
Casts or creates a word-sized unsigned value.
Syntax / common form
word(value);Parameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Variables / Data Types
bool
Description
Boolean type that stores true or false.
Syntax / common form
bool value;Parameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Variables / Data Types
byte
Description
8-bit unsigned integer type, commonly used for raw byte values.
Syntax / common form
byte value;Parameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
Exact size can vary by board architecture. Check the board family when range matters.
Variables / Data Types
char
Description
Character type, usually an 8-bit value storing a character or small integer.
Syntax / common form
char value;Parameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Variables / Data Types
float
Description
Floating-point numeric type used for decimal values.
Syntax / common form
float value;Parameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Variables / Data Types
int
Description
Integer type used for whole numbers. Size depends on the board architecture.
Syntax / common form
int value;Parameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
Exact size can vary by board architecture. Check the board family when range matters.
Variables / Data Types
long
Description
Larger signed integer type used when int is not large enough.
Syntax / common form
long value;Parameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
Exact size can vary by board architecture. Check the board family when range matters.
Variables / Data Types
short
Description
Short signed integer type.
Syntax / common form
short value;Parameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
Exact size can vary by board architecture. Check the board family when range matters.
Variables / Data Types
size_t
Description
Unsigned integer type used to represent sizes and counts.
Syntax / common form
size_t value;Parameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
Exact size can vary by board architecture. Check the board family when range matters.
Variables / Data Types
string
Description
C-style character array string.
Syntax / common form
string value;Parameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Variables / Data Types
String
Description
Arduino String object class for handling text with methods and operators.
Syntax / common form
String value;Parameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
On small-memory boards, heavy String use can fragment memory. For critical projects, consider fixed character buffers.
Variables / Data Types
String append operator
Description
Operator reference for comparing, joining, indexing, or modifying Arduino String objects.
Syntax / common form
String a = "hello";
String b = "world";
// operator syntax depends on operationParameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
On small-memory boards, heavy String use can fragment memory. For critical projects, consider fixed character buffers.
Variables / Data Types
String comparison operators
Description
Operator reference for comparing, joining, indexing, or modifying Arduino String objects.
Syntax / common form
String a = "hello";
String b = "world";
// operator syntax depends on operationParameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
On small-memory boards, heavy String use can fragment memory. For critical projects, consider fixed character buffers.
Variables / Data Types
String concatenation operator
Description
Operator reference for comparing, joining, indexing, or modifying Arduino String objects.
Syntax / common form
String a = "hello";
String b = "world";
// operator syntax depends on operationParameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
On small-memory boards, heavy String use can fragment memory. For critical projects, consider fixed character buffers.
Variables / Data Types
String different-from operator
Description
Operator reference for comparing, joining, indexing, or modifying Arduino String objects.
Syntax / common form
String a = "hello";
String b = "world";
// operator syntax depends on operationParameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
On small-memory boards, heavy String use can fragment memory. For critical projects, consider fixed character buffers.
Variables / Data Types
String element access operator
Description
Operator reference for comparing, joining, indexing, or modifying Arduino String objects.
Syntax / common form
String a = "hello";
String b = "world";
// operator syntax depends on operationParameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
On small-memory boards, heavy String use can fragment memory. For critical projects, consider fixed character buffers.
Variables / Data Types
String greater-than operator
Description
Operator reference for comparing, joining, indexing, or modifying Arduino String objects.
Syntax / common form
String a = "hello";
String b = "world";
// operator syntax depends on operationParameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
On small-memory boards, heavy String use can fragment memory. For critical projects, consider fixed character buffers.
Variables / Data Types
String greater-than-or-equal-to operator
Description
Operator reference for comparing, joining, indexing, or modifying Arduino String objects.
Syntax / common form
String a = "hello";
String b = "world";
// operator syntax depends on operationParameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
On small-memory boards, heavy String use can fragment memory. For critical projects, consider fixed character buffers.
Variables / Data Types
String less-than operator
Description
Operator reference for comparing, joining, indexing, or modifying Arduino String objects.
Syntax / common form
String a = "hello";
String b = "world";
// operator syntax depends on operationParameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
On small-memory boards, heavy String use can fragment memory. For critical projects, consider fixed character buffers.
Variables / Data Types
String less-than-or-equal-to operator
Description
Operator reference for comparing, joining, indexing, or modifying Arduino String objects.
Syntax / common form
String a = "hello";
String b = "world";
// operator syntax depends on operationParameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
On small-memory boards, heavy String use can fragment memory. For critical projects, consider fixed character buffers.
Variables / Data Types
String.c_str()
Description
Returns a C-style null-terminated character pointer for the String.
Syntax / common form
const char* p = myString.c_str();Parameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
On small-memory boards, heavy String use can fragment memory. For critical projects, consider fixed character buffers.
Variables / Data Types
String.charAt()
Description
Returns the character at a specified index.
Syntax / common form
char c = myString.charAt(index);Parameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
On small-memory boards, heavy String use can fragment memory. For critical projects, consider fixed character buffers.
Variables / Data Types
String.compareTo()
Description
Compares two strings and returns ordering information.
Syntax / common form
int result = myString.compareTo(otherString);Parameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
On small-memory boards, heavy String use can fragment memory. For critical projects, consider fixed character buffers.
Variables / Data Types
String.concat()
Description
Appends another value to the end of the String.
Syntax / common form
myString.concat(value);Parameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
On small-memory boards, heavy String use can fragment memory. For critical projects, consider fixed character buffers.
Variables / Data Types
String.endsWith()
Description
Tests whether the String ends with a specified suffix.
Syntax / common form
bool ok = myString.endsWith(suffix);Parameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
On small-memory boards, heavy String use can fragment memory. For critical projects, consider fixed character buffers.
Variables / Data Types
String.equals()
Description
Tests whether the String equals another value exactly.
Syntax / common form
bool ok = myString.equals(otherString);Parameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
On small-memory boards, heavy String use can fragment memory. For critical projects, consider fixed character buffers.
Variables / Data Types
String.equalsIgnoreCase()
Description
Tests equality while ignoring letter case.
Syntax / common form
bool ok = myString.equalsIgnoreCase(otherString);Parameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
On small-memory boards, heavy String use can fragment memory. For critical projects, consider fixed character buffers.
Variables / Data Types
String.getBytes()
Description
Copies String bytes into a byte buffer.
Syntax / common form
myString.getBytes(buffer, bufferSize);Parameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
On small-memory boards, heavy String use can fragment memory. For critical projects, consider fixed character buffers.
Variables / Data Types
String.indexOf()
Description
Finds the first index of a character or substring.
Syntax / common form
int i = myString.indexOf(value);Parameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
On small-memory boards, heavy String use can fragment memory. For critical projects, consider fixed character buffers.
Variables / Data Types
String.lastIndexOf()
Description
Finds the last index of a character or substring.
Syntax / common form
int i = myString.lastIndexOf(value);Parameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
On small-memory boards, heavy String use can fragment memory. For critical projects, consider fixed character buffers.
Variables / Data Types
String.length()
Description
Returns the number of characters in the String.
Syntax / common form
unsigned int n = myString.length();Parameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
On small-memory boards, heavy String use can fragment memory. For critical projects, consider fixed character buffers.
Variables / Data Types
String.remove()
Description
Removes characters from the String.
Syntax / common form
myString.remove(index);
myString.remove(index, count);Parameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
On small-memory boards, heavy String use can fragment memory. For critical projects, consider fixed character buffers.
Variables / Data Types
String.replace()
Description
Replaces matching characters or substrings.
Syntax / common form
myString.replace(find, replace);Parameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
On small-memory boards, heavy String use can fragment memory. For critical projects, consider fixed character buffers.
Variables / Data Types
String.reserve()
Description
Pre-allocates memory for a String to reduce fragmentation.
Syntax / common form
myString.reserve(size);Parameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
On small-memory boards, heavy String use can fragment memory. For critical projects, consider fixed character buffers.
Variables / Data Types
String.setCharAt()
Description
Changes the character at a selected index.
Syntax / common form
myString.setCharAt(index, character);Parameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
On small-memory boards, heavy String use can fragment memory. For critical projects, consider fixed character buffers.
Variables / Data Types
String.startsWith()
Description
Tests whether the String begins with a specified prefix.
Syntax / common form
bool ok = myString.startsWith(prefix);Parameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
On small-memory boards, heavy String use can fragment memory. For critical projects, consider fixed character buffers.
Variables / Data Types
String.substring()
Description
Extracts part of a String.
Syntax / common form
String part = myString.substring(from);
String part = myString.substring(from, to);Parameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
On small-memory boards, heavy String use can fragment memory. For critical projects, consider fixed character buffers.
Variables / Data Types
String.toCharArray()
Description
Copies the String into a C-style character array.
Syntax / common form
myString.toCharArray(buffer, bufferSize);Parameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
On small-memory boards, heavy String use can fragment memory. For critical projects, consider fixed character buffers.
Variables / Data Types
String.toDouble()
Description
Converts the String to a double value when supported.
Syntax / common form
double value = myString.toDouble();Parameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
On small-memory boards, heavy String use can fragment memory. For critical projects, consider fixed character buffers.
Variables / Data Types
String.toFloat()
Description
Converts the String to a float value.
Syntax / common form
float value = myString.toFloat();Parameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
On small-memory boards, heavy String use can fragment memory. For critical projects, consider fixed character buffers.
Variables / Data Types
String.toInt()
Description
Converts the String to an integer value.
Syntax / common form
long value = myString.toInt();Parameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
On small-memory boards, heavy String use can fragment memory. For critical projects, consider fixed character buffers.
Variables / Data Types
String.toLowerCase()
Description
Converts the String to lowercase in place.
Syntax / common form
myString.toLowerCase();Parameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
On small-memory boards, heavy String use can fragment memory. For critical projects, consider fixed character buffers.
Variables / Data Types
String.toUpperCase()
Description
Converts the String to uppercase in place.
Syntax / common form
myString.toUpperCase();Parameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
On small-memory boards, heavy String use can fragment memory. For critical projects, consider fixed character buffers.
Variables / Data Types
String.trim()
Description
Removes leading and trailing whitespace from the String.
Syntax / common form
myString.trim();Parameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
On small-memory boards, heavy String use can fragment memory. For critical projects, consider fixed character buffers.
Variables / Data Types
unsigned char
Description
8-bit unsigned character/integer type.
Syntax / common form
unsigned char value;Parameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
Exact size can vary by board architecture. Check the board family when range matters.
Variables / Data Types
unsigned int
Description
Unsigned integer type that cannot represent negative values.
Syntax / common form
unsigned int value;Parameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
Exact size can vary by board architecture. Check the board family when range matters.
Variables / Data Types
word
Description
Unsigned 16-bit value on many Arduino platforms.
Syntax / common form
word value;Parameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
Exact size can vary by board architecture. Check the board family when range matters.
Variables / Utilities
PROGMEM
Description
Places constant data into program memory/flash on platforms where this saves RAM.
Syntax / common form
PROGMEM value;Parameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Variables / Utilities
sizeof()
Description
Returns the number of bytes used by a type or variable.
Syntax / common form
sizeof(variable);
sizeof(type);Parameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Variables / Variable Scope Qualifiers
const
Description
Qualifier that marks a value as read-only after initialization.
Syntax / common form
const value;Parameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Variables / Variable Scope Qualifiers
scope
Description
Describes where a variable can be seen or used in a program.
Syntax / common form
scope value;Parameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Variables / Variable Scope Qualifiers
volatile
Description
Qualifier for variables that may change unexpectedly, often inside interrupts.
Syntax / common form
volatile value;Parameters / values
Variable name, type, value, or object instance depending on the entry.
Returns / result
Not applicable unless the entry is a conversion function or sizeof().
Notes
Use this entry as a quick reference and verify board-specific behavior when needed.
Relays for Automation Projects
Relays are a common item used to power units requiring a higher voltage or current than a microcontroller can handle and/or a unit or sensor that has a high electrical or current consumption. For automation its usually connected to a microcontroller and sensor that turns something on when a specific data point is reached or detected and turned off when the data point no longer exists or is valid.
An example would be if you had a microcontroller such as an arduino connected to a PIR sensor and a relay connected to a camera. You could configure the arduino to activate the relay when the PIR detects a heat source nearby, say if someone were entering your room or if you wanted to watch what your pet pig was doing when you let it outside. Being that the required voltage and current ratings are well outside the arduino’s capability -about an amp of current and 125VAC– you would have to connect the camera to a relay to safely power and control it. But how do you know which relay is right for you?
The Ultimate Guide to G-Code for 3D Printing
If you’ve ever fired up your 3D printer and watched it spring to life, you may have wondered: How does it know what to do? The answer is G-code. This is the magical language that tells your printer how to move, how hot to get, how fast to extrude filament, and much more. But don’t worry, G-code isn’t a foreign language – once you understand it, you’ll be controlling your printer like a seasoned pro.
This guide will walk you through every G-code command you’ll need to know for 3D printing. By the end, you’ll have the power to manipulate your 3D prints with precision and confidence. Ready to become a G-code wizard? Let’s dive in!
What Exactly Is G-Code?
Before we dive into the G-code commands, let’s first break down what it actually is. Think of G-code as a list of instructions for your 3D printer, similar to a recipe. It tells your printer where to go, how to extrude filament, and how hot things should get.
G-code is used to control every aspect of the printing process, from moving the print head to adjusting temperatures and speeds. The good news? G-code isn’t hard to understand once you know the basics. And as you get more comfortable with it, you’ll realize just how much control you have over the printing process!
Continue reading “The Ultimate Guide to G-Code for 3D Printing”
uBlock Origin For Internet Privacy lvl 2
Now things are heating up. Not really– more like getting more detailed and kinda tedious, but if you want to be more secure then you have to go in detail. This will be very detailed, but will be broken down into small bite sized pieces per the usual. So let’s get started.
uBlock Origin is a very privacy respecting app that allows users to block most privacy intrusive elements a website presents by blocking various scripts on a website.
To add and activate in your Firefox click the triple lines in the upper right hand of your Firefox window and select “Add ons and Themes“. in the search box type uBlock Origin. Select “Add to Firefox”. Its up to you whether or not you want it to run in Private Windows, but it is an option.
Cookie AutoDelete for Internet Privacy
Cookie AutoDelete is a powerful resource that stops cookies from following you around and analyzing your clicks, website visits, and recording what you look at by automatically clearing these cookies by event based rules you establish in the Settings page of the app. Whether you login to a website or are passively checking it out, cookies are loaded into your computer, though it doesn’t always mean its for nefarious purposes. There are several types of cookies that have various danger levels in terms of risk to your internet privacy.
| Cookie Name | Application/ Use | Risk To Privacy |
|---|---|---|
| Zombie Cookie | Persistent Internet Tracking. A regenerative cookie that is hard to remove | Extreme |
| 3rd Party Cookie | A cookie on one website that is hosted on another site. | High |
| Tracking Cookie | Traffic monitoring | Medium |
| Session Cookie | Used to track user data just for that session. Typically deletes upon session end | Low |
| Persistent Cookie | Cookie that stays on a user’s computer even after the session ends | Medium- Low |
| Authentication Cookies | Utilized when logged into a website | Low |
| 1st Party Cookies | A cookie from a website that’s hosted on that website | Low |