LM75B.cpp

00001 #include "mbed.h"
00002 #include "LM75B.h"
00003 #include "af_mgr.h"
00004 
00005 /* Register list */
00006 #define PTR_CONF    0x01
00007 #define PTR_TEMP    0x00
00008 #define PTR_TOS     0x03
00009 #define PTR_THYST   0x02
00010 
00011 /* Configuration register */
00012 /* B[7:5] : Reserved */
00013 /* B[4:3] : OS_F_QUE[1:0] OS fault queue value */
00014 #define CONFIG_QUE_1    0x00
00015 #define CONFIG_QUE_2    (0x01 << 3)
00016 #define CONFIG_QUE_4    (0x10 << 3)
00017 #define CONFIG_QUE_6    (0x11 << 3) 
00018 /* B[2] : OS_POL  0 = OS active LOW,  1 = OS active HIGH */
00019 #define CONFIG_OS_POL_L 0x00
00020 #define CONFIG_OS_POL_H (0x01 << 2)
00021 /* B[1] : OS_COMP_INT 0 = OS comparator, 1 = OS interrupt */
00022 #define CONFIG_OS_COMP  0x00
00023 #define CONFIG_OS_INT   (0x01 << 1)
00024 /* B[0] : SHUTDOWN    0 = normal, 1 = shutdown */
00025 #define CONFIG_NORMARL  0x00
00026 #define CONFIG_SHUTDOWN 0x01
00027 
00028 /* Temperature register */
00029 /* D[15:5] = 11 bit data 0.125 * temp data */
00030 /* D[4:0] : reserved */
00031 
00032 /* Tos register */
00033 /* D[15:7] = 9 bit data */
00034 /* D[6:0] : reserved */
00035 
00036 /* Thyst register */
00037 /* D[15:7] = 9 ibt data */
00038 /* D[6:0] : reserved */
00039 
00040 LM75B::LM75B(I2C *i2c, int addr) : m_addr(addr<<1) {
00041     p_i2c = i2c ;
00042     p_i2c->frequency(100000); /* 100kHz */
00043     // activate the peripheral
00044 }
00045 
00046 LM75B::~LM75B() { }
00047 
00048 int LM75B::temp(int8_t *temp)
00049 {
00050     int result ;
00051     char t[1] = { 0x00 } ;
00052     result = p_i2c->write(m_addr, t, 1, true) ;
00053     if (result == 0) {
00054         result = p_i2c->read(m_addr, t, 1) ;
00055     }
00056     if (result == 0) {
00057         *temp = (int8_t)t[0] ;
00058     }
00059     return( result ) ;
00060 }
00061 
00062 int LM75B::getTemp(float *temp)
00063 {
00064     int result ;
00065     char t[2] = { 0, 0 } ;
00066     int16_t iTemp = 0 ;
00067     result = p_i2c->write(m_addr, t, 1) ; /* write pointer byte 0x00 */
00068     if (result == 0) {
00069         result = p_i2c->read(m_addr, t, 2) ; /* read MSB, LSB */
00070     }
00071     if (result == 0) {
00072         iTemp = (t[0] << 8) | t[1] ;
00073         iTemp >>= 5 ;
00074         *temp = 0.125 * iTemp ;
00075     }
00076     return( result ) ;
00077 }
00078 
00079 int LM75B::getConfig(uint8_t ptr_byte, uint8_t *config_data) 
00080 {
00081     int result ;
00082     char config = 0x00 ; /* default value */
00083     result = p_i2c->write(m_addr, (char*)(&ptr_byte), 1, true) ;
00084     if (result == 0) {
00085         result = p_i2c->read(m_addr, &config, 1) ;
00086     }
00087     if (result == 0) {
00088         *config_data = config ;
00089     }
00090     return( result ) ;
00091 }
00092 
00093 int LM75B::setConfig(uint8_t ptr_byte, uint8_t config_data) 
00094 {
00095     int result ;
00096     char t[2] ;
00097     t[0] = ptr_byte ;
00098     t[1] = config_data ;
00099     result = p_i2c->write(m_addr, t, 2, true) ;
00100     return( result ) ;
00101 }
00102 
00103 int LM75B::readRegs(int addr, uint8_t * data, int len) 
00104 {
00105     int result ;
00106     char t[1] = {addr};
00107     __disable_irq() ; // Disable Interrupts
00108     result = p_i2c->write(m_addr, t, 1, true);
00109     if (result == 0) {
00110         result = p_i2c->read(m_addr, (char *)data, len);
00111     }
00112     __enable_irq() ; // Enable Interrupts
00113     return( result ) ;
00114 }
00115 
00116 int LM75B::writeRegs(uint8_t * data, int len) {
00117     int result ;
00118     __disable_irq() ; // Disable Interrupts
00119     result = p_i2c->write(m_addr, (char *)data, len);
00120     __enable_irq() ; // Enable Interrupts
00121     return( result ) ;
00122 }