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); } }
OneWire.h
- Committer:
- ivank
- Date:
- 2012-12-18
- Revision:
- 2:07da4deb7135
- Parent:
- 0:b9cd1d4dcc1f
File content as of revision 2:07da4deb7135:
#ifndef ONEWIRE_H #define ONEWIRE_H #include "mbed.h" #define FALSE 0 #define TRUE 1 #define ONEWIRE_DS18B20_FAMILY 0x28 enum OneWireDeviceCmd { SET_TEMPERATURE_RESOLUTION = 0, GET_TEMPERATURE }; typedef uint8_t DeviceAddress[8]; typedef DeviceAddress* DeviceAddresses; class OneWire { public: OneWire(PinName pin); uint8_t reset(void); uint8_t readByte(void); void writeByte(uint8_t val); void select(uint8_t* devAddr); void resetSearch(void); uint8_t search(uint8_t* devAddr); void sendGlobalCommand(uint8_t); DeviceAddresses* getFoundDevAddresses(); uint8_t getFoundDevNum(); private: DigitalInOut DIO; static const uint8_t dscrc_table[]; DeviceAddresses* foundDevAdresses; uint8_t foundDevNum; uint8_t lastDiscrep; uint8_t doneFlag; uint8_t dowcrc; uint8_t readBit(void); void writeBit(uint8_t bitval); void skip(); uint8_t calcCRC(uint8_t x); void findDevAddresses(void); }; #include "OneWireDevice.h" #endif