diff options
Diffstat (limited to 'libraries/SoftwareSerial/SoftwareSerial.cpp')
| -rw-r--r-- | libraries/SoftwareSerial/SoftwareSerial.cpp | 486 |
1 files changed, 0 insertions, 486 deletions
diff --git a/libraries/SoftwareSerial/SoftwareSerial.cpp b/libraries/SoftwareSerial/SoftwareSerial.cpp deleted file mode 100644 index 0a16ff7..0000000 --- a/libraries/SoftwareSerial/SoftwareSerial.cpp +++ /dev/null @@ -1,486 +0,0 @@ -/*
-SoftwareSerial.cpp (formerly NewSoftSerial.cpp) -
-Multi-instance software serial library for Arduino/Wiring
--- Interrupt-driven receive and other improvements by ladyada
- (http://ladyada.net)
--- Tuning, circular buffer, derivation from class Print/Stream,
- multi-instance support, porting to 8MHz processors,
- various optimizations, PROGMEM delay tables, inverse logic and
- direct port writing by Mikal Hart (http://www.arduiniana.org)
--- Pin change interrupt macros by Paul Stoffregen (http://www.pjrc.com)
--- 20MHz processor support by Garrett Mace (http://www.macetech.com)
--- ATmega1280/2560 support by Brett Hagman (http://www.roguerobotics.com/)
-
-This library is free software; you can redistribute it and/or
-modify it under the terms of the GNU Lesser General Public
-License as published by the Free Software Foundation; either
-version 2.1 of the License, or (at your option) any later version.
-
-This library is distributed in the hope that it will be useful,
-but WITHOUT ANY WARRANTY; without even the implied warranty of
-MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
-Lesser General Public License for more details.
-
-You should have received a copy of the GNU Lesser General Public
-License along with this library; if not, write to the Free Software
-Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
-
-The latest version of this library can always be found at
-http://arduiniana.org.
-*/
-
-// When set, _DEBUG co-opts pins 11 and 13 for debugging with an
-// oscilloscope or logic analyzer. Beware: it also slightly modifies
-// the bit times, so don't rely on it too much at high baud rates
-#define _DEBUG 0
-#define _DEBUG_PIN1 11
-#define _DEBUG_PIN2 13
-//
-// Includes
-//
-#include <avr/interrupt.h>
-#include <avr/pgmspace.h>
-#include <Arduino.h>
-#include <SoftwareSerial.h>
-#include <util/delay_basic.h>
-
-//
-// Statics
-//
-SoftwareSerial *SoftwareSerial::active_object = 0;
-char SoftwareSerial::_receive_buffer[_SS_MAX_RX_BUFF];
-volatile uint8_t SoftwareSerial::_receive_buffer_tail = 0;
-volatile uint8_t SoftwareSerial::_receive_buffer_head = 0;
-
-//
-// Debugging
-//
-// This function generates a brief pulse
-// for debugging or measuring on an oscilloscope.
-#if _DEBUG
-inline void DebugPulse(uint8_t pin, uint8_t count)
-{
- volatile uint8_t *pport = portOutputRegister(digitalPinToPort(pin));
-
- uint8_t val = *pport;
- while (count--)
- {
- *pport = val | digitalPinToBitMask(pin);
- *pport = val;
- }
-}
-#else
-inline void DebugPulse(uint8_t, uint8_t) {}
-#endif
-
-//
-// Private methods
-//
-
-/* static */
-inline void SoftwareSerial::tunedDelay(uint16_t delay) {
- _delay_loop_2(delay);
-}
-
-// This function sets the current object as the "listening"
-// one and returns true if it replaces another
-bool SoftwareSerial::listen()
-{
- if (!_rx_delay_stopbit)
- return false;
-
- if (active_object != this)
- {
- if (active_object)
- active_object->stopListening();
-
- _buffer_overflow = false;
- _receive_buffer_head = _receive_buffer_tail = 0;
- active_object = this;
-
- setRxIntMsk(true);
- return true;
- }
-
- return false;
-}
-
-// Stop listening. Returns true if we were actually listening.
-bool SoftwareSerial::stopListening()
-{
- if (active_object == this)
- {
- setRxIntMsk(false);
- active_object = NULL;
- return true;
- }
- return false;
-}
-
-//
-// The receive routine called by the interrupt handler
-//
-void SoftwareSerial::recv()
-{
-
-#if GCC_VERSION < 40302
-// Work-around for avr-gcc 4.3.0 OSX version bug
-// Preserve the registers that the compiler misses
-// (courtesy of Arduino forum user *etracer*)
- asm volatile(
- "push r18 \n\t"
- "push r19 \n\t"
- "push r20 \n\t"
- "push r21 \n\t"
- "push r22 \n\t"
- "push r23 \n\t"
- "push r26 \n\t"
- "push r27 \n\t"
- ::);
-#endif
-
- uint8_t d = 0;
-
- // If RX line is high, then we don't see any start bit
- // so interrupt is probably not for us
- if (_inverse_logic ? rx_pin_read() : !rx_pin_read())
- {
- // Disable further interrupts during reception, this prevents
- // triggering another interrupt directly after we return, which can
- // cause problems at higher baudrates.
- setRxIntMsk(false);
-
- // Wait approximately 1/2 of a bit width to "center" the sample
- tunedDelay(_rx_delay_centering);
- DebugPulse(_DEBUG_PIN2, 1);
-
- // Read each of the 8 bits
- for (uint8_t i=8; i > 0; --i)
- {
- tunedDelay(_rx_delay_intrabit);
- d >>= 1;
- DebugPulse(_DEBUG_PIN2, 1);
- if (rx_pin_read())
- d |= 0x80;
- }
-
- if (_inverse_logic)
- d = ~d;
-
- // if buffer full, set the overflow flag and return
- uint8_t next = (_receive_buffer_tail + 1) % _SS_MAX_RX_BUFF;
- if (next != _receive_buffer_head)
- {
- // save new data in buffer: tail points to where byte goes
- _receive_buffer[_receive_buffer_tail] = d; // save new byte
- _receive_buffer_tail = next;
- }
- else
- {
- DebugPulse(_DEBUG_PIN1, 1);
- _buffer_overflow = true;
- }
-
- // skip the stop bit
- tunedDelay(_rx_delay_stopbit);
- DebugPulse(_DEBUG_PIN1, 1);
-
- // Re-enable interrupts when we're sure to be inside the stop bit
- setRxIntMsk(true);
-
- }
-
-#if GCC_VERSION < 40302
-// Work-around for avr-gcc 4.3.0 OSX version bug
-// Restore the registers that the compiler misses
- asm volatile(
- "pop r27 \n\t"
- "pop r26 \n\t"
- "pop r23 \n\t"
- "pop r22 \n\t"
- "pop r21 \n\t"
- "pop r20 \n\t"
- "pop r19 \n\t"
- "pop r18 \n\t"
- ::);
-#endif
-}
-
-uint8_t SoftwareSerial::rx_pin_read()
-{
- return *_receivePortRegister & _receiveBitMask;
-}
-
-//
-// Interrupt handling
-//
-
-/* static */
-inline void SoftwareSerial::handle_interrupt()
-{
- if (active_object)
- {
- active_object->recv();
- }
-}
-
-#if defined(PCINT0_vect)
-ISR(PCINT0_vect)
-{
- SoftwareSerial::handle_interrupt();
-}
-#endif
-
-#if defined(PCINT1_vect)
-ISR(PCINT1_vect, ISR_ALIASOF(PCINT0_vect));
-#endif
-
-#if defined(PCINT2_vect)
-ISR(PCINT2_vect, ISR_ALIASOF(PCINT0_vect));
-#endif
-
-#if defined(PCINT3_vect)
-ISR(PCINT3_vect, ISR_ALIASOF(PCINT0_vect));
-#endif
-
-//
-// Constructor
-//
-SoftwareSerial::SoftwareSerial(uint8_t receivePin, uint8_t transmitPin, bool inverse_logic /* = false */) :
- _rx_delay_centering(0),
- _rx_delay_intrabit(0),
- _rx_delay_stopbit(0),
- _tx_delay(0),
- _buffer_overflow(false),
- _inverse_logic(inverse_logic)
-{
- setTX(transmitPin);
- setRX(receivePin);
-}
-
-//
-// Destructor
-//
-SoftwareSerial::~SoftwareSerial()
-{
- end();
-}
-
-void SoftwareSerial::setTX(uint8_t tx)
-{
- // First write, then set output. If we do this the other way around,
- // the pin would be output low for a short while before switching to
- // output hihg. Now, it is input with pullup for a short while, which
- // is fine. With inverse logic, either order is fine.
- digitalWrite(tx, _inverse_logic ? LOW : HIGH);
- pinMode(tx, OUTPUT);
- _transmitBitMask = digitalPinToBitMask(tx);
- uint8_t port = digitalPinToPort(tx);
- _transmitPortRegister = portOutputRegister(port);
-}
-
-void SoftwareSerial::setRX(uint8_t rx)
-{
- pinMode(rx, INPUT);
- if (!_inverse_logic)
- digitalWrite(rx, HIGH); // pullup for normal logic!
- _receivePin = rx;
- _receiveBitMask = digitalPinToBitMask(rx);
- uint8_t port = digitalPinToPort(rx);
- _receivePortRegister = portInputRegister(port);
-}
-
-uint16_t SoftwareSerial::subtract_cap(uint16_t num, uint16_t sub) {
- if (num > sub)
- return num - sub;
- else
- return 1;
-}
-
-//
-// Public methods
-//
-
-void SoftwareSerial::begin(long speed)
-{
- _rx_delay_centering = _rx_delay_intrabit = _rx_delay_stopbit = _tx_delay = 0;
-
- // Precalculate the various delays, in number of 4-cycle delays
- uint16_t bit_delay = (F_CPU / speed) / 4;
-
- // 12 (gcc 4.8.2) or 13 (gcc 4.3.2) cycles from start bit to first bit,
- // 15 (gcc 4.8.2) or 16 (gcc 4.3.2) cycles between bits,
- // 12 (gcc 4.8.2) or 14 (gcc 4.3.2) cycles from last bit to stop bit
- // These are all close enough to just use 15 cycles, since the inter-bit
- // timings are the most critical (deviations stack 8 times)
- _tx_delay = subtract_cap(bit_delay, 15 / 4);
-
- // Only setup rx when we have a valid PCINT for this pin
- if (digitalPinToPCICR(_receivePin)) {
- #if GCC_VERSION > 40800
- // Timings counted from gcc 4.8.2 output. This works up to 115200 on
- // 16Mhz and 57600 on 8Mhz.
- //
- // When the start bit occurs, there are 3 or 4 cycles before the
- // interrupt flag is set, 4 cycles before the PC is set to the right
- // interrupt vector address and the old PC is pushed on the stack,
- // and then 75 cycles of instructions (including the RJMP in the
- // ISR vector table) until the first delay. After the delay, there
- // are 17 more cycles until the pin value is read (excluding the
- // delay in the loop).
- // We want to have a total delay of 1.5 bit time. Inside the loop,
- // we already wait for 1 bit time - 23 cycles, so here we wait for
- // 0.5 bit time - (71 + 18 - 22) cycles.
- _rx_delay_centering = subtract_cap(bit_delay / 2, (4 + 4 + 75 + 17 - 23) / 4);
-
- // There are 23 cycles in each loop iteration (excluding the delay)
- _rx_delay_intrabit = subtract_cap(bit_delay, 23 / 4);
-
- // There are 37 cycles from the last bit read to the start of
- // stopbit delay and 11 cycles from the delay until the interrupt
- // mask is enabled again (which _must_ happen during the stopbit).
- // This delay aims at 3/4 of a bit time, meaning the end of the
- // delay will be at 1/4th of the stopbit. This allows some extra
- // time for ISR cleanup, which makes 115200 baud at 16Mhz work more
- // reliably
- _rx_delay_stopbit = subtract_cap(bit_delay * 3 / 4, (37 + 11) / 4);
- #else // Timings counted from gcc 4.3.2 output
- // Note that this code is a _lot_ slower, mostly due to bad register
- // allocation choices of gcc. This works up to 57600 on 16Mhz and
- // 38400 on 8Mhz.
- _rx_delay_centering = subtract_cap(bit_delay / 2, (4 + 4 + 97 + 29 - 11) / 4);
- _rx_delay_intrabit = subtract_cap(bit_delay, 11 / 4);
- _rx_delay_stopbit = subtract_cap(bit_delay * 3 / 4, (44 + 17) / 4);
- #endif
-
-
- // Enable the PCINT for the entire port here, but never disable it
- // (others might also need it, so we disable the interrupt by using
- // the per-pin PCMSK register).
- *digitalPinToPCICR(_receivePin) |= _BV(digitalPinToPCICRbit(_receivePin));
- // Precalculate the pcint mask register and value, so setRxIntMask
- // can be used inside the ISR without costing too much time.
- _pcint_maskreg = digitalPinToPCMSK(_receivePin);
- _pcint_maskvalue = _BV(digitalPinToPCMSKbit(_receivePin));
-
- tunedDelay(_tx_delay); // if we were low this establishes the end
- }
-
-#if _DEBUG
- pinMode(_DEBUG_PIN1, OUTPUT);
- pinMode(_DEBUG_PIN2, OUTPUT);
-#endif
-
- listen();
-}
-
-void SoftwareSerial::setRxIntMsk(bool enable)
-{
- if (enable)
- *_pcint_maskreg |= _pcint_maskvalue;
- else
- *_pcint_maskreg &= ~_pcint_maskvalue;
-}
-
-void SoftwareSerial::end()
-{
- stopListening();
-}
-
-
-// Read data from buffer
-int SoftwareSerial::read()
-{
- if (!isListening())
- return -1;
-
- // Empty buffer?
- if (_receive_buffer_head == _receive_buffer_tail)
- return -1;
-
- // Read from "head"
- uint8_t d = _receive_buffer[_receive_buffer_head]; // grab next byte
- _receive_buffer_head = (_receive_buffer_head + 1) % _SS_MAX_RX_BUFF;
- return d;
-}
-
-int SoftwareSerial::available()
-{
- if (!isListening())
- return 0;
-
- return (_receive_buffer_tail + _SS_MAX_RX_BUFF - _receive_buffer_head) % _SS_MAX_RX_BUFF;
-}
-
-size_t SoftwareSerial::write(uint8_t b)
-{
- if (_tx_delay == 0) {
- setWriteError();
- return 0;
- }
-
- // By declaring these as local variables, the compiler will put them
- // in registers _before_ disabling interrupts and entering the
- // critical timing sections below, which makes it a lot easier to
- // verify the cycle timings
- volatile uint8_t *reg = _transmitPortRegister;
- uint8_t reg_mask = _transmitBitMask;
- uint8_t inv_mask = ~_transmitBitMask;
- uint8_t oldSREG = SREG;
- bool inv = _inverse_logic;
- uint16_t delay = _tx_delay;
-
- if (inv)
- b = ~b;
-
- cli(); // turn off interrupts for a clean txmit
-
- // Write the start bit
- if (inv)
- *reg |= reg_mask;
- else
- *reg &= inv_mask;
-
- tunedDelay(delay);
-
- // Write each of the 8 bits
- for (uint8_t i = 8; i > 0; --i)
- {
- if (b & 1) // choose bit
- *reg |= reg_mask; // send 1
- else
- *reg &= inv_mask; // send 0
-
- tunedDelay(delay);
- b >>= 1;
- }
-
- // restore pin to natural state
- if (inv)
- *reg &= inv_mask;
- else
- *reg |= reg_mask;
-
- SREG = oldSREG; // turn interrupts back on
- tunedDelay(_tx_delay);
-
- return 1;
-}
-
-void SoftwareSerial::flush()
-{
- // There is no tx buffering, simply return
-}
-
-int SoftwareSerial::peek()
-{
- if (!isListening())
- return -1;
-
- // Empty buffer?
- if (_receive_buffer_head == _receive_buffer_tail)
- return -1;
-
- // Read from "head"
- return _receive_buffer[_receive_buffer_head];
-}
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