AT30TSE75X.cpp

00001 #include "AT30TSE75X.h"
00002 
00003 AT30TSE75X::AT30TSE75X(PinName sda, PinName scl) : at30tse75x_i2c(sda, scl), resolution(AT30TSE_CONFIG_RES_9_bit) {
00004     at30tse75x_i2c.frequency(10000);
00005 }
00006 AT30TSE75X::~AT30TSE75X() { }
00007 
00008 float AT30TSE75X::read_temp() {
00009     uint8_t bufferwrite[1];
00010     uint8_t buffer[2];
00011     float temperature;
00012     uint16_t data;
00013     buffer[0] = 0;
00014     buffer[1] = 0;
00015 
00016     at30tse75x_i2c.read((AT30TSE_TEMPERATURE_TWI_ADDR << 1 ),(char *)buffer,AT30TSE_TEMPERATURE_REG_SIZE,false);
00017 
00018 
00019     data = (buffer[0] << 8) | buffer[1];
00020     int8_t sign = 1;
00021 
00022     /* Check if negative and clear sign bit. */
00023     if (data & (1 << 15)) {
00024         sign *= -1;
00025         data &= ~(1 << 15);
00026     }
00027 
00028     /* Convert to temperature. */
00029     switch (this->resolution) {
00030     case AT30TSE_CONFIG_RES_9_bit:
00031         data = (data >> 7);
00032         (temperature) = data * sign * 0.5;
00033         break;
00034 
00035     case AT30TSE_CONFIG_RES_10_bit:
00036         data = (data >> 6);
00037         (temperature) = data * sign * 0.25;
00038         break;
00039 
00040     case AT30TSE_CONFIG_RES_11_bit:
00041         data = (data >> 5);
00042         (temperature) = data * sign * 0.125;
00043         break;
00044 
00045     case AT30TSE_CONFIG_RES_12_bit:
00046         data = (data >> 4);
00047         (temperature) = data * sign * 0.0625;
00048         break;
00049 
00050     default:
00051         break;
00052     }
00053     return temperature;
00054 }
00055 
00056 uint8_t AT30TSE75X:: read_eeprom(uint8_t *data, uint8_t length, uint8_t word_addr, uint8_t page) {  
00057     uint8_t buff[20];
00058     buff[0]  = (word_addr & 0x0F) | ((0x0F & page) << 4);
00059         
00060     at30tse75x_i2c.write((int)(AT30TSE_EEPROM_TWI_ADDR << 1),(char *)buff,1,false);
00061     return at30tse75x_i2c.read((int)(AT30TSE_EEPROM_TWI_ADDR << 1),(char *)data,length,false);  
00062 }
00063 
00064 uint8_t AT30TSE75X:: write_eeprom(uint8_t *data, uint8_t length, uint8_t word_addr, uint8_t page)
00065 {
00066     uint8_t buff[length+1];;
00067     buff[0] = (word_addr & 0x0F) | ((0x0F & page) << 4);
00068     for(int i = 0; i < length; i++)
00069     {
00070         buff[i+1] = *data++;
00071     }
00072     return  at30tse75x_i2c.write((int)(AT30TSE_EEPROM_TWI_ADDR << 1),(char *)buff,(length + 1),false);
00073 }