/* Includes ------------------------------------------------------------------*/
#include "stm32l1xx_i2c.h"
#include "i2c_tsensor.h"
#include "stm32l1xx_rcc.h"


__IO uint32_t  LM75_Timeout = LM75_LONG_TIMEOUT; 


/* ------------------------------------*/

void LM75_Init(void)
{
  GPIO_InitTypeDef  GPIO_InitStructure;
  I2C_InitTypeDef   I2C_InitStructure;
  
  RCC_APB1PeriphClockCmd(RCC_APB1Periph_I2C1, ENABLE);
  RCC_AHBPeriphClockCmd(RCC_AHBPeriph_GPIOB, ENABLE);
 
  GPIO_PinAFConfig(GPIOB, GPIO_PinSource6, GPIO_AF_I2C1); 
  GPIO_PinAFConfig(GPIOB, GPIO_PinSource7, GPIO_AF_I2C1);
  
  /*!< Configure LM75_I2C pins: SCL */
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
  GPIO_InitStructure.GPIO_PuPd  = GPIO_PuPd_NOPULL;
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_40MHz;
  GPIO_InitStructure.GPIO_OType = GPIO_OType_OD;
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6|GPIO_Pin_7;
  GPIO_Init(GPIOB, &GPIO_InitStructure);
  
  I2C_DeInit(I2C2);
  
  /*!< LM75_I2C Init */
  I2C_InitStructure.I2C_Mode = I2C_Mode_I2C;
  I2C_InitStructure.I2C_DutyCycle = I2C_DutyCycle_2;
  I2C_InitStructure.I2C_Ack = I2C_Ack_Enable;
  I2C_InitStructure.I2C_AcknowledgedAddress = I2C_AcknowledgedAddress_7bit;
  I2C_InitStructure.I2C_ClockSpeed = 400000;
  I2C_Init(I2C1, &I2C_InitStructure);
  
  /*!< LM75_I2C Init */
  I2C_Cmd(I2C1, ENABLE);
  I2C_Init(I2C1, &I2C_InitStructure);
}
/* ------------------------------------*/

uint16_t LM75_ReadTemp(void)
{   
  uint16_t tmp = 0;
        
  /* Enable the I2C peripheral */
  I2C_GenerateSTART(I2C1, ENABLE);
  
  /* Test on EV5 and clear it */
  while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_MODE_SELECT));
  LCD_GLASS_DisplayString("ACK0"); Delay(1000);
  
  /* Send device address for write */
  I2C_Send7bitAddress(I2C1, 0x90, I2C_Direction_Transmitter);
  
  /* Test on EV6 and clear it */
  while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED));
  LCD_GLASS_DisplayString("ACK1"); Delay(1000);
  
  /* Clear EV6 by setting again the PE bit */
  I2C_Cmd(I2C1, ENABLE);
  
  /* Send the device's internal address to write to */
  I2C_SendData(I2C1, 0x00);  
  
  /* Test on EV8 and clear it */
  while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_BYTE_TRANSMITTED));
  LCD_GLASS_DisplayString("ACK2"); Delay(1000);
  
  /* Send START condition a second time */  
  I2C_GenerateSTART(I2C1, ENABLE);
  
  /* Test on EV5 and clear it */
  while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_MODE_SELECT));
  LCD_GLASS_DisplayString("ACK3"); Delay(1000);
  
  /* Send LM75 address for read */
  I2C_Send7bitAddress(I2C1, 0x90, I2C_Direction_Receiver);
  
  /* Test on EV6 and clear it */
  while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_RECEIVER_MODE_SELECTED));
  LCD_GLASS_DisplayString("ACK4"); Delay(1000);
  
  /* Disable Acknowledgement */
  I2C_AcknowledgeConfig(I2C1, DISABLE);  
  
  /* Send STOP Condition */
  I2C_GenerateSTOP(I2C1, ENABLE);
  while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_BYTE_RECEIVED)){}  
  
  /*!< Store LM75_I2C received data */
  tmp = (I2C_ReceiveData(I2C1)<<8);
  tmp |= I2C_ReceiveData(I2C1);
   
  /*!< Return Temperature value */
  return (uint16_t)(tmp);
}