/*
 * rtc1308.cpp
 *
 *  Created on: Nov 4, 2014
 *      Author: Alan Aguilar Sologuren
 */

#include <rtc1308.h>
#include <Wire.h>

namespace te_rtc{

/*!
 * \fn initialization
 * \brief Inicializacion del modulo que controlara al RTC DS1308.
 */
void initialization(void) {

	pinMode(CLKIN,OUTPUT);
	attachInterrupt(PPS,ISR_gnss_pps, RISING);
}

/*!
 * \fn configure
 * \brief Configura el IC DS1308 para operacion con un PPS de GNSS como tick.
 * \param rtc estructura que contien informacion de configuracion.
 * \see rtc_config_struct
 */
void configure(rtc_config_struct &rtc) {

	uint8_t *ctl_byte = (uint8_t*)&rtc.ctl_byte;
	uint8_t *clk_halt = (uint8_t*)&rtc.clk_halt;

	Wire.beginTransmission(DS1308_CTRL_ID);
	Wire.write(DS1308_CTL_ADD);
	Wire.write(*clk_halt);
	Wire.endTransmission();

	Wire.beginTransmission(DS1308_CTRL_ID);
	Wire.write(DS1308_CTL_ADD);
	// CLKIN com 1Hz de entrada (1PPS)
	Wire.write(*ctl_byte);
	//Wire.write(1<<ECLK|0<<OSF|0<<LOS|0<<BBCLK|0<<RS1|0<<RS0);
	Wire.endTransmission();
}

/*!
 * \fn set_time
 * \brief Setea el tiempo especificado en tm, en el IC DS1308.
 * \param tm estructura que contien informacion de tiempo.
 * \see tmElements_t
 */
void set_time(tmElements_t &tm) {

	Wire.beginTransmission(DS1308_CTRL_ID);
	// start with Clock Control and the Seconds register
	Wire.write(DS1308_SEC_ADD);
	Wire.write((uint8_t)0x80); // Set clock control bit to 1. This stops the clock
	Wire.write(dec2bcd(tm.Minute));
	Wire.write(dec2bcd(tm.Hour));      // sets 24 hour format
	Wire.write(dec2bcd(tm.Wday));
	Wire.write(dec2bcd(tm.Day));
	Wire.write(dec2bcd(tm.Month));
	Wire.write(dec2bcd(tmYearToY2k(tm.Year)));
	Wire.endTransmission();

	Wire.beginTransmission(DS1308_CTRL_ID);
	// Address the Clock Control and the Seconds register
	Wire.write(DS1308_SEC_ADD);
	// Set clock control bit to 0 and number of seconds.  This starts the clock
	Wire.write(dec2bcd(tm.Second));
	Wire.endTransmission();
}

/*!
 * \fn activate_pps
 * \brief Activa la generacion de una senal de 1Hz (PPS) desde el RTC DS1308. Este
 * PPS debe estar sincronizado con el PPS del GNSS.
 */
void activate_pps(void) {
	Wire.beginTransmission(DS1308_CTRL_ID);
	Wire.write(DS1308_CTL_ADD);
	// CLKIN com 1Hz de salida (1PPS)
	Wire.write(0<<ECLK|0<<OSF|1<<SQWE|0<<LOS|0<<BBCLK|0<<RS1|0<<RS0);
	Wire.endTransmission();
}

///////////////////////////////////////////////////////////////////////////////


/*!
 * \fn read_ram
 * \brief Lee un buffer de la memoria RAM interna del RTC DS1308, de la
 * direccion especificada.
 * \param addr direccion relativa a la RAM (0 es la primera) del registro
 * en DS1308.
 * \param buff  Direccion del buffer al cual se copiaran los valores.
 * \param cnt  Numero de elementos acpiar del DS1308.
 * \return estatus
 *  0 success
 *  2 error: address send, nack received
 *  3 error: data send, nack received
 *  4 other twi error
 */
uint8_t read_ram(uint8_t regaddr, uint8_t *pbuf, uint8_t cnt) {

	uint8_t nread=0;
	while( (cnt > 0) && ( regaddr < DS1308_RAM_REGS ) ) {
		Wire.beginTransmission(DS1308_CTRL_ID);
		Wire.write(regaddr+DS1308_RAM_BASE);
		Wire.endTransmission();
		Wire.requestFrom((uint8_t)DS1308_CTRL_ID, cnt);
		while(Wire.available() && (cnt > 0) && (regaddr < DS1308_RAM_REGS) ) {
			pbuf[nread] = Wire.read();
			nread++; cnt--; regaddr++;
		}  /* while */
	}
	return (nread);
}

/*!
 * \fn write_ram
 * \brief Escribe un valor en la memoria RAM interna del RTC DS1308, en la
 * direccion especificada.
 * \param addr direccion relativa a la RAM (0 es la primera) del registro
 * en DS1308.
 * \param val  valor que se desea escribir en el registro.
 * \return estatus
 *  0 success
 *  2 error: address send, nack received
 *  3 error: data send, nack received
 *  4 other twi error
 */
uint8_t write_ram(uint8_t regaddr, uint8_t val) {

	uint8_t rc=0;
	if (regaddr >= DS1308_RAM_REGS) return (DS1308_RAM_REGS); // 0 thru 51
	Wire.beginTransmission(DS1308_CTRL_ID);
	Wire.write(regaddr+DS1308_RAM_BASE);
	Wire.write(val);
	rc = Wire.endTransmission();
	return(rc);
}

/*!
 * \fn write_ram
 * \brief Escribe el contenido de un buffer de cnt elementos en la memoria
 * RAM interna del RTC DS1308, en la direccion especificada.
 * \param addr direccion relativa a la RAM (0 es la primera) del inicio del
 * buffer en DS1308.
 * \param pbuf direccion del buffer a copiar en la RAM del DS1308.
 * \param cnt  Numero de elementos a copiar.
 * \return estatus
 *  0 success
 *  2 error: address send, nack received
 *  3 error: data send, nack received
 *  4 other twi error
 */
uint8_t write_ram(uint8_t regaddr, const uint8_t *pbuf,uint8_t cnt) {

	uint8_t nbytes, rc=0;
	if (regaddr >= DS1308_RAM_REGS) return (DS1308_RAM_REGS); // 0 thru 55
	if (regaddr+cnt > DS1308_RAM_REGS) cnt = DS1308_RAM_REGS-regaddr;
	while (cnt > 0) {
		nbytes = min(cnt, BUFFER_LENGTH-1);
		Wire.beginTransmission(DS1308_CTRL_ID);
		Wire.write(regaddr+DS1308_RAM_BASE);
		Wire.write((uint8_t*)pbuf, nbytes);
		rc = Wire.endTransmission();
		cnt -=nbytes;
		regaddr+=nbytes;
		pbuf +=nbytes;
	}
	return(rc);
}


// Convert Decimal to Binary Coded Decimal (BCD). 2 digits only
inline uint8_t dec2bcd(uint8_t val) {
	return val + 6 * (val / 10);
}


}// end namespace rtc