OWI.h

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#ifndef SOFTWARE_OWI_H
#define SOFTWARE_OWI_H

#include "OWI.h"
#include "GPIO.h"

namespace Software {
template<BOARD::pin_t PIN>
class OWI : public ::OWI {
public:
  OWI()
  {
    m_pin.open_drain();
  }

  virtual bool reset()
  {
    uint8_t retry = RESET_RETRY_MAX;
    bool res;
    do {
      m_pin.output();
      delayMicroseconds(490);
      noInterrupts();
      m_pin.input();
      delayMicroseconds(70);
      res = m_pin;
      interrupts();
      delayMicroseconds(410);
    } while (retry-- && res);
    return (res == 0);
  }

  virtual uint8_t read(uint8_t bits = CHARBITS)
  {
    uint8_t adjust = CHARBITS - bits;
    uint8_t res = 0;
    while (bits--) {
      noInterrupts();
      m_pin.output();
      delayMicroseconds(6);
      m_pin.input();
      delayMicroseconds(9);
      res >>= 1;
      res |= (m_pin ? 0x80 : 0x00);
      interrupts();
      delayMicroseconds(55);
    }
    res >>= adjust;
    return (res);
  }

  virtual void write(uint8_t value, uint8_t bits = CHARBITS)
  {
    while (bits--) {
      noInterrupts();
      m_pin.output();
      if (value & 0x01) {
        delayMicroseconds(6);
        m_pin.input();
        delayMicroseconds(64);
      }
      else {
        delayMicroseconds(60);
        m_pin.input();
        delayMicroseconds(10);
      }
      interrupts();
      value >>= 1;
    }
  }

  using ::OWI::read;
  using ::OWI::write;

protected:
  GPIO<PIN> m_pin;
};
};
#endif