Rob Dobson / Onewire

Library to communicate with Maxim OneWire protocol devices Modified timings and IRQ overrides

Dependents:   RdGasUseMonitor

Fork of Onewire by Simon Barker

Onewire.h@6:d2452e9b169b, 2015-10-05 (annotated)

Committer:
Bobty
Date:
Mon Oct 05 14:03:29 2015 +0000
Revision:
6:d2452e9b169b
Parent:
4:b678c7c8203c
Child:
7:0a87f8c2d9e6
Changed return code from search to be more meaningful about the reason for failure

Who changed what in which revision?

UserRevisionLine numberNew contents of line
simonbarker 0:d961f715d82b 1 #ifndef Onewire_h
simonbarker 0:d961f715d82b 2 #define Onewire_h
simonbarker 0:d961f715d82b 3
simonbarker 0:d961f715d82b 4 #include "mbed.h"
simonbarker 0:d961f715d82b 5
Bobty 4:b678c7c8203c 6 #define ONEWIRE_ADDR_BYTES 8
Bobty 4:b678c7c8203c 7
Bobty 6:d2452e9b169b 8 const int ONEWIRE_OK = 0;
Bobty 6:d2452e9b169b 9 const int ONEWIRE_SEARCH_ALL_DONE = 1;
Bobty 6:d2452e9b169b 10 const int ONEWIRE_SEARCH_INIT_FAIL = 2;
Bobty 6:d2452e9b169b 11 const int ONEWIRE_SEARCH_NOT_FOUND = 3;
simonbarker 0:d961f715d82b 12
Bobty 6:d2452e9b169b 13 class Onewire
Bobty 6:d2452e9b169b 14 {
Bobty 6:d2452e9b169b 15
Bobty 6:d2452e9b169b 16 public:
Bobty 1:8e9464e05ddf 17 Onewire(PinName oneBus);
Bobty 1:8e9464e05ddf 18 void writeBit(int bit);
simonbarker 0:d961f715d82b 19 int readBit();
simonbarker 0:d961f715d82b 20 int init();
simonbarker 0:d961f715d82b 21 int readByte();
simonbarker 0:d961f715d82b 22 void writeByte(char data);
simonbarker 0:d961f715d82b 23 unsigned char CRC(unsigned char* addr, unsigned char len);
simonbarker 0:d961f715d82b 24
Bobty 1:8e9464e05ddf 25 // Clear the search state so that if will start from the beginning again.
Bobty 1:8e9464e05ddf 26 void reset_search();
Bobty 6:d2452e9b169b 27 // Look for the next device.
Bobty 6:d2452e9b169b 28 // Returns
Bobty 6:d2452e9b169b 29 // ONEWIRE_OK if a new address has been returned.
Bobty 6:d2452e9b169b 30 // ONEWIRE_SEARCH_ALL_DONE = all devices found
Bobty 6:d2452e9b169b 31 // ONEWIRE_SEARCH_INIT_FAIL = failed to init
Bobty 6:d2452e9b169b 32 // ONEWIRE_SEARCH_NOT_FOUND = no devices found
Bobty 6:d2452e9b169b 33 // It might be a good idea to check the CRC to make sure you didn't
Bobty 1:8e9464e05ddf 34 // get garbage. The order is deterministic. You will always get
Bobty 1:8e9464e05ddf 35 // the same devices in the same order.
Bobty 1:8e9464e05ddf 36 uint8_t search(uint8_t *newAddr);
Bobty 1:8e9464e05ddf 37
simonbarker 0:d961f715d82b 38 private:
Bobty 1:8e9464e05ddf 39 DigitalInOut oneBus_;
Bobty 1:8e9464e05ddf 40
Bobty 1:8e9464e05ddf 41 // search state
Bobty 1:8e9464e05ddf 42 unsigned char _search_ROM_NO[8];
Bobty 1:8e9464e05ddf 43 uint8_t _search_LastDiscrepancy;
Bobty 1:8e9464e05ddf 44 uint8_t _search_LastFamilyDiscrepancy;
Bobty 1:8e9464e05ddf 45 uint8_t _search_LastDeviceFlag;
simonbarker 0:d961f715d82b 46 };
simonbarker 0:d961f715d82b 47 #endif