LM75B.cpp

00001 #include "mbed.h"
00002 #include "LM75B.h"
00003 
00004 /* Register list */
00005 #define PTR_CONF    0x01
00006 #define PTR_TEMP    0x00
00007 #define PTR_TOS     0x03
00008 #define PTR_THYST   0x02
00009 
00010 /* Configuration register */
00011 /* B[7:5] : Reserved */
00012 /* B[4:3] : OS_F_QUE[1:0] OS fault queue value */
00013 #define CONFIG_QUE_1    0x00
00014 #define CONFIG_QUE_2    (0x01 << 3)
00015 #define CONFIG_QUE_4    (0x10 << 3)
00016 #define CONFIG_QUE_6    (0x11 << 3) 
00017 /* B[2] : OS_POL  0 = OS active LOW,  1 = OS active HIGH */
00018 #define CONFIG_OS_POL_L 0x00
00019 #define CONFIG_OS_POL_H (0x01 << 2)
00020 /* B[1] : OS_COMP_INT 0 = OS comparator, 1 = OS interrupt */
00021 #define CONFIG_OS_COMP  0x00
00022 #define CONFIG_OS_INT   (0x01 << 1)
00023 /* B[0] : SHUTDOWN    0 = normal, 1 = shutdown */
00024 #define CONFIG_NORMARL  0x00
00025 #define CONFIG_SHUTDOWN 0x01
00026 
00027 /* Temperature register */
00028 /* D[15:5] = 11 bit data 0.125 * temp data */
00029 /* D[4:0] : reserved */
00030 
00031 /* Tos register */
00032 /* D[15:7] = 9 bit data */
00033 /* D[6:0] : reserved */
00034 
00035 /* Thyst register */
00036 /* D[15:7] = 9 ibt data */
00037 /* D[6:0] : reserved */
00038 
00039 LM75B::LM75B(PinName sda, PinName scl, int addr) : m_i2c(sda, scl), m_addr(addr<<1) {
00040     m_i2c.frequency(I2C_FREQ_100KHZ);
00041     // activate the peripheral
00042 }
00043 
00044 LM75B::~LM75B() { }
00045 
00046 int8_t LM75B::temp(void)
00047 {
00048     char t[1] = { 0x00 } ;
00049     int8_t temp ;
00050     m_i2c.write(m_addr, t, 1, true) ;
00051     m_i2c.read(m_addr, t, 1) ;
00052     temp = (int8_t)t[0] ;
00053     return( temp ) ;
00054 }
00055 
00056 void LM75B::getTemp(float *temp)
00057 {
00058     char t[2] ;
00059     int16_t iTemp = 0 ;
00060     m_i2c.read(m_addr, t, 2) ; /* read MSB, LSB */
00061     iTemp = (t[0] << 8) | t[1] ;
00062     iTemp >>= 5 ;
00063     *temp = 0.125 * iTemp ;
00064 }
00065 
00066 uint8_t LM75B::getConfig(uint8_t ptr_byte) 
00067 {
00068     char config ;
00069     m_i2c.write(m_addr, (char*)(&ptr_byte), 1, true) ;
00070     m_i2c.read(m_addr, &config, 1) ;
00071     return( config ) ;
00072 }
00073 
00074 void LM75B::setConfig(uint8_t ptr_byte, uint8_t config_data) 
00075 {
00076     char t[2] ;
00077     t[0] = ptr_byte ;
00078     t[1] = config_data ;
00079     m_i2c.write(m_addr, t, 2, true) ;
00080 }
00081 
00082 void LM75B::readRegs(int addr, uint8_t * data, int len) {
00083     char t[1] = {addr};
00084     m_i2c.write(m_addr, t, 1, true);
00085     m_i2c.read(m_addr, (char *)data, len);
00086 }
00087 
00088 void LM75B::writeRegs(uint8_t * data, int len) {
00089     m_i2c.write(m_addr, (char *)data, len);
00090 }