/*
  BuffSerial.cpp v.01 - serial with transmit buffer library for Wiring
  Created by Kochetkov Aleksey, 03.07.2009
*/
#include <stdio.h>

#include "BuffSerial.h"

// serial init
void BuffSerial::begin(long speed) {
#if defined(__AVR_ATmega8__)
  UCSRB = _BV(RXCIE) | _BV(RXEN) | _BV(TXCIE) | _BV(TXEN);   // enable rx, tx inerrputs
  UBRRH = ((F_CPU / 16 + speed / 2) / speed - 1) >> 8;       // usart speed
  UBRRL = ((F_CPU / 16 + speed / 2) / speed - 1);
#else
  UCSR0B = (_BV(RXCIE0) | _BV(RXEN0) | _BV(TXCIE0) | _BV(TXEN0));  // enable rx, tx inerrputs
  UBRR0H = ((F_CPU / 16 + speed / 2) / speed - 1) >> 8;            // usart speed
  UBRR0L = ((F_CPU / 16 + speed / 2) / speed - 1);
#endif
  rxBegin = rxEnd = 0;
  txBegin = txEnd = txOverflow = 0;
  txFull  = 0;
}

//USART Rx Complete
#if defined(__AVR_ATmega8__)
SIGNAL(SIG_UART_RECV)
#else
SIGNAL(USART_RX_vect)
#endif
{
#if defined(__AVR_ATmega8__)
  bSerial.rxBuffer[bSerial.rxEnd] = UDR;
#else
  bSerial.rxBuffer[bSerial.rxEnd] = UDR0;
#endif
  if (bSerial.rxEnd < RX_BUFF_SIZE) bSerial.rxEnd++;
}

//USART Tx Complete
#if defined(__AVR_ATmega8__)
SIGNAL(SIG_UART_TRANS)
#else
SIGNAL(USART_TX_vect)
#endif
{
  if (bSerial.txEnd != bSerial.txBegin || bSerial.txFull != 0) {
#if defined(__AVR_ATmega8__)
    UDR  = bSerial.txBuffer[bSerial.txBegin];  // Send buffer
#else
    UDR0 = bSerial.txBuffer[bSerial.txBegin];  // Send buffer
#endif
    bSerial.txFull = 0;
    bSerial.txBegin++;
    if (bSerial.txBegin == TX_BUFF_SIZE) bSerial.txBegin = 0;
  }

}

// send byte to serial or buffer if bisy
void BuffSerial::sendByte(uint8_t data) {
  if (txFull) {
    txOverflow++;
  } else {
    uint8_t oldSREG = SREG;
    cli();
#if defined(__AVR_ATmega8__)
    if (txEnd != txBegin || (UCSRA & _BV(UDRE)) == 0) {
#else
    if (txEnd != txBegin || (UCSR0A & _BV(UDRE0)) == 0) {
#endif
      txBuffer[txEnd] = data;
      txEnd++;
      if (txEnd == TX_BUFF_SIZE) txEnd = 0;
      if (txEnd == txBegin) txFull = 1;          // buffer overflow
    } else {
#if defined(__AVR_ATmega8__)
      UDR  = data;
#else
      UDR0 = data;
#endif
    }
    SREG = oldSREG;
  }
}

// print string
void BuffSerial::print(const char *pBuf) {
  while (*pBuf)	{
    sendByte(*pBuf++);
  }
}

void BuffSerial::print(const char pBuf) {
  sendByte(pBuf);
}


void BuffSerial::println(const char *pBuf) {
  print(pBuf);
  println();
}

void BuffSerial::println(const char pBuf) {
  print(pBuf);
  println();
}

void BuffSerial::println(void) {
  print("\r\n");
}

void BuffSerial::printHex4(uint8_t data) {
  uint8_t c = data & 0x0f;
  c += c < 10 ? '0' : 'A' - 10 ;
  sendByte(c);
}

void BuffSerial::printHex8(uint8_t data) {
  printHex4(data >> 4);
  printHex4(data);
}

void BuffSerial::printDec(uint8_t data) {
  uint8_t buf[3];
  uint8_t i = 0;
  if (data == 0) {
    sendByte('0');
    return;
  }

  while (data > 0) {
    buf[i++] = data % 10;
    data /= 10;
  }
  for (; i > 0; i--)
    sendByte((buf[i - 1] < 10 ? '0' + buf[i - 1] : 'A' + buf[i - 1] - 10));
}

// check rx buffer not empty
bool BuffSerial::rxEnabled(void) {
  return rxEnd;
}

uint8_t BuffSerial::rxRead(void) {
#if defined(__AVR_ATmega8__)
  cbi(UCSRB, RXCIE);                           // disable RX complete interrupt
#else
  cbi(UCSR0B, RXCIE0);                         // disable RX complete interrupt
#endif
  uint8_t readkey = rxBuffer[rxBegin];         // read begin of received Buffer
  rxBegin++;
  if (rxBegin == rxEnd) rxBegin = rxEnd = 0;   // if Buffer is empty reset Buffer
#if defined(__AVR_ATmega8__)
  sbi(UCSRB, RXCIE);                           // enable RX complete interrupt
#else
  sbi(UCSR0B, RXCIE0);                         // enable RX complete interrupt
#endif

  return readkey;
}

BuffSerial bSerial;