1wire.h

00001 #ifndef _1WIRE_H
00002 #define _1WIRE_H
00003 
00004 /* Dallas 1-wire driver with DS18B20 temperature sensor support
00005  *
00006  * Copyright (c) 2014 Ales Povalac, MIT License
00007  *
00008  * Permission is hereby granted, free of charge, to any person obtaining a copy of this software 
00009  * and associated documentation files (the "Software"), to deal in the Software without restriction, 
00010  * including without limitation the rights to use, copy, modify, merge, publish, distribute, 
00011  * sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is 
00012  * furnished to do so, subject to the following conditions:
00013  *
00014  * The above copyright notice and this permission notice shall be included in all copies or 
00015  * substantial portions of the Software.
00016  *
00017  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING 
00018  * BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 
00019  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, 
00020  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 
00021  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
00022  */
00023 
00024 class OneWire
00025 {
00026 public:
00027     OneWire(PinName OwUp, PinName OwDn, PinName OwIn);
00028 
00029     void ConvertAll(bool wait);
00030     int ReadTemperature(uint8_t *ROMID, int *result);
00031     
00032     int First(uint8_t *ROMID);
00033     int Next(uint8_t *ROMID);
00034 
00035     void WriteByte(uint8_t data);
00036     uint8_t ReadByte(void);
00037     void SendCmd(uint8_t *ROMID, uint8_t cmd);
00038     void CRC(uint8_t x, uint8_t *crc);
00039     
00040 private:
00041     DigitalOut _OwUp;
00042     DigitalOut _OwDn;
00043     DigitalIn _OwIn;
00044 
00045     uint8_t OW_LastDevice;
00046     uint8_t OW_LastDiscrepancy;
00047     uint8_t OW_LastFamilyDiscrepancy;
00048 
00049     int Reset(void);
00050     void WriteBit(int bit);
00051     int ReadBit(void);
00052 };
00053         
00054 
00055 /* INTERNAL CONSTANTS everything below this line */
00056 
00057 #define ERR_BADCRC      0x8000
00058 #define ERR_BADFAMILY   0x8001
00059 
00060 /* Return codes for OWFirst()/OWNext() */
00061 #define OW_BADWIRE      -3
00062 #define OW_BADCRC       -2
00063 #define OW_NOPRESENCE   -1
00064 #define OW_NOMODULES    0
00065 #define OW_FOUND        1
00066 
00067 /* General 1 wire commands */
00068 #define OW_SEARCH_ROM_CMD   0xF0
00069 #define OW_READ_ROM_CMD     0x33
00070 #define OW_MATCH_ROM_CMD    0x55
00071 #define OW_SKIP_ROM_CMD     0xCC
00072 
00073 /* DS1820 commands */
00074 #define OW_CONVERT_T_CMD    0x44
00075 #define OW_RD_SCR_CMD       0xBE
00076 #define OW_WR_SCR_CMD       0x4E
00077 
00078 
00079 /* 1-wire delays */
00080 #define DELAY_A() wait_us(6)
00081 #define DELAY_B() wait_us(64)
00082 #define DELAY_C() wait_us(60)
00083 #define DELAY_D() wait_us(10)
00084 #define DELAY_E() wait_us(9)
00085 #define DELAY_F() wait_us(55)
00086 #define DELAY_G()
00087 #define DELAY_H() wait_us(480)
00088 #define DELAY_I() wait_us(70) 
00089 #define DELAY_J() wait_us(410)
00090 
00091 /* Other */
00092 #define CONVERT_T_DELAY 750
00093 
00094 #endif