HardwareSerial::end()

Abstract

The HardwareSerial::end() ends the serial communication and sets RX and TX pins to normal input/output mode.

The HardwareSerial::end() sets UCSR0B register.

Source Code

The HardwareSerial::end() is defined in hardware/arduino/avr/cores/arduino/HardwareSerial.cpp as below.

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void HardwareSerial::end()
{
  // wait for transmission of outgoing data
  flush();
 
  cbi(*_ucsrb, RXEN0);
  cbi(*_ucsrb, TXEN0);
  cbi(*_ucsrb, RXCIE0);
  cbi(*_ucsrb, UDRIE0);
   
  // clear any received data
  _rx_buffer_head = _rx_buffer_tail;
}

No inputs, no outputs.

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void HardwareSerial::end()
{

Call HardwareSerial::flush() to send untransmitted data.

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// wait for transmission of outgoing data
flush();

Then sets the register.

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cbi(*_ucsrb, _rxen);
cbi(*_ucsrb, _txen);
cbi(*_ucsrb, _rxcie);  
cbi(*_ucsrb, _udrie);

Clears RXEn, TXEn, RXCIEn and UDUIEn in ucsrb(UCSR0B) using cbi().

Finally clears receive buffer.

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  // clear any received data
  _rx_buffer_head = _rx_buffer_tail;
}

version

Arduino AVR Boards 1.8.6

Last Update

August 25, 2019