MSS / LM75B

LM75B Digital temperature sensor and thermal watchdog

Dependents:   testLM75B testSensor TCPSocket_Client

LM75B.cpp@0:1cf64e89f29d, 2016-07-06 (annotated)

Committer:
Rhyme
Date:
Wed Jul 06 07:02:52 2016 +0000
Revision:
0:1cf64e89f29d
Child:
1:61987c319606
First working version, only temp mode is implemented.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
Rhyme 0:1cf64e89f29d 1 #include "mbed.h"
Rhyme 0:1cf64e89f29d 2 #include "LM75B.h"
Rhyme 0:1cf64e89f29d 3
Rhyme 0:1cf64e89f29d 4 /* Register list */
Rhyme 0:1cf64e89f29d 5 #define PTR_CONF 0x01
Rhyme 0:1cf64e89f29d 6 #define PTR_TEMP 0x00
Rhyme 0:1cf64e89f29d 7 #define PTR_TOS 0x03
Rhyme 0:1cf64e89f29d 8 #define PTR_THYST 0x02
Rhyme 0:1cf64e89f29d 9
Rhyme 0:1cf64e89f29d 10 /* Configuration register */
Rhyme 0:1cf64e89f29d 11 /* B[7:5] : Reserved */
Rhyme 0:1cf64e89f29d 12 /* B[4:3] : OS_F_QUE[1:0] OS fault queue value */
Rhyme 0:1cf64e89f29d 13 #define CONFIG_QUE_1 0x00
Rhyme 0:1cf64e89f29d 14 #define CONFIG_QUE_2 (0x01 << 3)
Rhyme 0:1cf64e89f29d 15 #define CONFIG_QUE_4 (0x10 << 3)
Rhyme 0:1cf64e89f29d 16 #define CONFIG_QUE_6 (0x11 << 3)
Rhyme 0:1cf64e89f29d 17 /* B[2] : OS_POL 0 = OS active LOW, 1 = OS active HIGH */
Rhyme 0:1cf64e89f29d 18 #define CONFIG_OS_POL_L 0x00
Rhyme 0:1cf64e89f29d 19 #define CONFIG_OS_POL_H (0x01 << 2)
Rhyme 0:1cf64e89f29d 20 /* B[1] : OS_COMP_INT 0 = OS comparator, 1 = OS interrupt */
Rhyme 0:1cf64e89f29d 21 #define CONFIG_OS_COMP 0x00
Rhyme 0:1cf64e89f29d 22 #define CONFIG_OS_INT (0x01 << 1)
Rhyme 0:1cf64e89f29d 23 /* B[0] : SHUTDOWN 0 = normal, 1 = shutdown */
Rhyme 0:1cf64e89f29d 24 #define CONFIG_NORMARL 0x00
Rhyme 0:1cf64e89f29d 25 #define CONFIG_SHUTDOWN 0x01
Rhyme 0:1cf64e89f29d 26
Rhyme 0:1cf64e89f29d 27 /* Temperature register */
Rhyme 0:1cf64e89f29d 28 /* D[15:5] = 11 bit data 0.125 * temp data */
Rhyme 0:1cf64e89f29d 29 /* D[4:0] : reserved */
Rhyme 0:1cf64e89f29d 30
Rhyme 0:1cf64e89f29d 31
Rhyme 0:1cf64e89f29d 32
Rhyme 0:1cf64e89f29d 33 LM75B::LM75B(PinName sda, PinName scl, int addr) : m_i2c(sda, scl), m_addr(addr<<1) {
Rhyme 0:1cf64e89f29d 34 // activate the peripheral
Rhyme 0:1cf64e89f29d 35 }
Rhyme 0:1cf64e89f29d 36
Rhyme 0:1cf64e89f29d 37 LM75B::~LM75B() { }
Rhyme 0:1cf64e89f29d 38
Rhyme 0:1cf64e89f29d 39 int8_t LM75B::temp(void)
Rhyme 0:1cf64e89f29d 40 {
Rhyme 0:1cf64e89f29d 41 char t[1] = { 0x00 } ;
Rhyme 0:1cf64e89f29d 42 int8_t temp ;
Rhyme 0:1cf64e89f29d 43 m_i2c.write(m_addr, t, 1, true) ;
Rhyme 0:1cf64e89f29d 44 m_i2c.read(m_addr, t, 1) ;
Rhyme 0:1cf64e89f29d 45 temp = (int8_t)t[0] ;
Rhyme 0:1cf64e89f29d 46 return( temp ) ;
Rhyme 0:1cf64e89f29d 47 }
Rhyme 0:1cf64e89f29d 48
Rhyme 0:1cf64e89f29d 49 void LM75B::getTemp(float *temp)
Rhyme 0:1cf64e89f29d 50 {
Rhyme 0:1cf64e89f29d 51 char t[2] ;
Rhyme 0:1cf64e89f29d 52 int16_t iTemp = 0 ;
Rhyme 0:1cf64e89f29d 53 m_i2c.read(m_addr, t, 2) ; /* read MSB, LSB */
Rhyme 0:1cf64e89f29d 54 iTemp = (t[0] << 8) | t[1] ;
Rhyme 0:1cf64e89f29d 55 iTemp >>= 5 ;
Rhyme 0:1cf64e89f29d 56 *temp = 0.125 * iTemp ;
Rhyme 0:1cf64e89f29d 57 }
Rhyme 0:1cf64e89f29d 58
Rhyme 0:1cf64e89f29d 59 uint8_t LM75B::getConfig(uint8_t ptr_byte)
Rhyme 0:1cf64e89f29d 60 {
Rhyme 0:1cf64e89f29d 61 char config ;
Rhyme 0:1cf64e89f29d 62 m_i2c.write(m_addr, (char*)(&ptr_byte), 1, true) ;
Rhyme 0:1cf64e89f29d 63 m_i2c.read(m_addr, &config, 1) ;
Rhyme 0:1cf64e89f29d 64 return( config ) ;
Rhyme 0:1cf64e89f29d 65 }
Rhyme 0:1cf64e89f29d 66
Rhyme 0:1cf64e89f29d 67 void LM75B::setConfig(uint8_t ptr_byte, uint8_t config_data)
Rhyme 0:1cf64e89f29d 68 {
Rhyme 0:1cf64e89f29d 69 char t[2] ;
Rhyme 0:1cf64e89f29d 70 t[0] = ptr_byte ;
Rhyme 0:1cf64e89f29d 71 t[1] = config_data ;
Rhyme 0:1cf64e89f29d 72 m_i2c.write(m_addr, t, 2, true) ;
Rhyme 0:1cf64e89f29d 73 }
Rhyme 0:1cf64e89f29d 74
Rhyme 0:1cf64e89f29d 75 void LM75B::readRegs(int addr, uint8_t * data, int len) {
Rhyme 0:1cf64e89f29d 76 char t[1] = {addr};
Rhyme 0:1cf64e89f29d 77 m_i2c.write(m_addr, t, 1, true);
Rhyme 0:1cf64e89f29d 78 m_i2c.read(m_addr, (char *)data, len);
Rhyme 0:1cf64e89f29d 79 }
Rhyme 0:1cf64e89f29d 80
Rhyme 0:1cf64e89f29d 81 void LM75B::writeRegs(uint8_t * data, int len) {
Rhyme 0:1cf64e89f29d 82 m_i2c.write(m_addr, (char *)data, len);
Rhyme 0:1cf64e89f29d 83 }