OneWire Library lets you access 1-wire devices made by Maxim/Dallas, such as temperature sensors

Dependents:   OneWireTest mbed_blinky Affich_Lum_Moist Projetv0 ... more

#include "mbed.h"
#include "OneWire.h"

OneWire owBus(p21);

int main()
{
    char _id[16];
    DeviceAddresses* devAddresses = owBus.getFoundDevAddresses();
    uint8_t foundNum = owBus.getFoundDevNum();
    printf("OneWire: found %d devices\r\n", foundNum);

    while(1) {
        OneWireDeviceTemperature::startConversationForAll(&owBus, OWTEMP_11_BIT);
        for (uint8_t i = 0; i < foundNum; i++) {
            OneWireDevice* owDevice = OneWireDeviceFactory::init(&owBus, (*devAddresses)[i]);
            
            if (owDevice->getFamily() != ONEWIRE_DS18B20_FAMILY)    // currently only DS18B20 supports
                continue;

            owDevice->generateId(_id);
            printf("OneWire: device #%s = %.4f*C\r\n", _id, (float) owDevice->sendGetCommand(GET_TEMPERATURE));
            delete owDevice;            
        }
        
        wait(5);
    }
 }
Committer:
ivank
Date:
Tue Dec 18 11:40:28 2012 +0000
Revision:
2:07da4deb7135
Parent:
0:b9cd1d4dcc1f
- splited library to seprated files; - fixed bug with GET_TEMPERATURE & IRQ(interrupts) under RTOS

Who changed what in which revision?

UserRevisionLine numberNew contents of line
ivank 0:b9cd1d4dcc1f 1 #ifndef ONEWIRE_H
ivank 0:b9cd1d4dcc1f 2 #define ONEWIRE_H
ivank 0:b9cd1d4dcc1f 3
ivank 0:b9cd1d4dcc1f 4 #include "mbed.h"
ivank 0:b9cd1d4dcc1f 5
ivank 0:b9cd1d4dcc1f 6 #define FALSE 0
ivank 0:b9cd1d4dcc1f 7 #define TRUE 1
ivank 0:b9cd1d4dcc1f 8
ivank 0:b9cd1d4dcc1f 9 #define ONEWIRE_DS18B20_FAMILY 0x28
ivank 0:b9cd1d4dcc1f 10
ivank 0:b9cd1d4dcc1f 11 enum OneWireDeviceCmd {
ivank 0:b9cd1d4dcc1f 12 SET_TEMPERATURE_RESOLUTION = 0,
ivank 0:b9cd1d4dcc1f 13 GET_TEMPERATURE
ivank 0:b9cd1d4dcc1f 14 };
ivank 0:b9cd1d4dcc1f 15
ivank 0:b9cd1d4dcc1f 16 typedef uint8_t DeviceAddress[8];
ivank 0:b9cd1d4dcc1f 17 typedef DeviceAddress* DeviceAddresses;
ivank 0:b9cd1d4dcc1f 18
ivank 0:b9cd1d4dcc1f 19 class OneWire {
ivank 0:b9cd1d4dcc1f 20 public:
ivank 0:b9cd1d4dcc1f 21 OneWire(PinName pin);
ivank 0:b9cd1d4dcc1f 22
ivank 0:b9cd1d4dcc1f 23 uint8_t reset(void);
ivank 0:b9cd1d4dcc1f 24 uint8_t readByte(void);
ivank 0:b9cd1d4dcc1f 25 void writeByte(uint8_t val);
ivank 0:b9cd1d4dcc1f 26 void select(uint8_t* devAddr);
ivank 0:b9cd1d4dcc1f 27 void resetSearch(void);
ivank 0:b9cd1d4dcc1f 28
ivank 0:b9cd1d4dcc1f 29 uint8_t search(uint8_t* devAddr);
ivank 0:b9cd1d4dcc1f 30 void sendGlobalCommand(uint8_t);
ivank 0:b9cd1d4dcc1f 31 DeviceAddresses* getFoundDevAddresses();
ivank 0:b9cd1d4dcc1f 32 uint8_t getFoundDevNum();
ivank 0:b9cd1d4dcc1f 33
ivank 0:b9cd1d4dcc1f 34 private:
ivank 0:b9cd1d4dcc1f 35 DigitalInOut DIO;
ivank 0:b9cd1d4dcc1f 36 static const uint8_t dscrc_table[];
ivank 0:b9cd1d4dcc1f 37
ivank 0:b9cd1d4dcc1f 38 DeviceAddresses* foundDevAdresses;
ivank 0:b9cd1d4dcc1f 39 uint8_t foundDevNum;
ivank 0:b9cd1d4dcc1f 40
ivank 0:b9cd1d4dcc1f 41 uint8_t lastDiscrep;
ivank 0:b9cd1d4dcc1f 42 uint8_t doneFlag;
ivank 0:b9cd1d4dcc1f 43 uint8_t dowcrc;
ivank 0:b9cd1d4dcc1f 44
ivank 0:b9cd1d4dcc1f 45 uint8_t readBit(void);
ivank 0:b9cd1d4dcc1f 46 void writeBit(uint8_t bitval);
ivank 0:b9cd1d4dcc1f 47
ivank 0:b9cd1d4dcc1f 48 void skip();
ivank 0:b9cd1d4dcc1f 49 uint8_t calcCRC(uint8_t x);
ivank 0:b9cd1d4dcc1f 50 void findDevAddresses(void);
ivank 0:b9cd1d4dcc1f 51 };
ivank 0:b9cd1d4dcc1f 52
ivank 2:07da4deb7135 53 #include "OneWireDevice.h"
ivank 0:b9cd1d4dcc1f 54
ivank 0:b9cd1d4dcc1f 55 #endif