| 2529 |
kaklik |
1 |
#ifndef OneWire_h |
|
|
2 |
#define OneWire_h |
|
|
3 |
|
|
|
4 |
#include <inttypes.h> |
|
|
5 |
|
|
|
6 |
#if ARDUINO >= 100 |
|
|
7 |
#include "Arduino.h" // for delayMicroseconds, digitalPinToBitMask, etc |
|
|
8 |
#else |
|
|
9 |
#include "WProgram.h" // for delayMicroseconds |
|
|
10 |
#include "pins_arduino.h" // for digitalPinToBitMask, etc |
|
|
11 |
#endif |
|
|
12 |
|
|
|
13 |
// You can exclude certain features from OneWire. In theory, this |
|
|
14 |
// might save some space. In practice, the compiler automatically |
|
|
15 |
// removes unused code (technically, the linker, using -fdata-sections |
|
|
16 |
// and -ffunction-sections when compiling, and Wl,--gc-sections |
|
|
17 |
// when linking), so most of these will not result in any code size |
|
|
18 |
// reduction. Well, unless you try to use the missing features |
|
|
19 |
// and redesign your program to not need them! ONEWIRE_CRC8_TABLE |
|
|
20 |
// is the exception, because it selects a fast but large algorithm |
|
|
21 |
// or a small but slow algorithm. |
|
|
22 |
|
|
|
23 |
// you can exclude onewire_search by defining that to 0 |
|
|
24 |
#ifndef ONEWIRE_SEARCH |
|
|
25 |
#define ONEWIRE_SEARCH 1 |
|
|
26 |
#endif |
|
|
27 |
|
|
|
28 |
// You can exclude CRC checks altogether by defining this to 0 |
|
|
29 |
#ifndef ONEWIRE_CRC |
|
|
30 |
#define ONEWIRE_CRC 1 |
|
|
31 |
#endif |
|
|
32 |
|
|
|
33 |
// Select the table-lookup method of computing the 8-bit CRC |
|
|
34 |
// by setting this to 1. The lookup table enlarges code size by |
|
|
35 |
// about 250 bytes. It does NOT consume RAM (but did in very |
|
|
36 |
// old versions of OneWire). If you disable this, a slower |
|
|
37 |
// but very compact algorithm is used. |
|
|
38 |
#ifndef ONEWIRE_CRC8_TABLE |
|
|
39 |
#define ONEWIRE_CRC8_TABLE 1 |
|
|
40 |
#endif |
|
|
41 |
|
|
|
42 |
// You can allow 16-bit CRC checks by defining this to 1 |
|
|
43 |
// (Note that ONEWIRE_CRC must also be 1.) |
|
|
44 |
#ifndef ONEWIRE_CRC16 |
|
|
45 |
#define ONEWIRE_CRC16 1 |
|
|
46 |
#endif |
|
|
47 |
|
|
|
48 |
#define FALSE 0 |
|
|
49 |
#define TRUE 1 |
|
|
50 |
|
|
|
51 |
// Platform specific I/O definitions |
|
|
52 |
|
|
|
53 |
#if defined(__AVR__) |
|
|
54 |
#define PIN_TO_BASEREG(pin) (portInputRegister(digitalPinToPort(pin))) |
|
|
55 |
#define PIN_TO_BITMASK(pin) (digitalPinToBitMask(pin)) |
|
|
56 |
#define IO_REG_TYPE uint8_t |
|
|
57 |
#define IO_REG_ASM asm("r30") |
|
|
58 |
#define DIRECT_READ(base, mask) (((*(base)) & (mask)) ? 1 : 0) |
|
|
59 |
#define DIRECT_MODE_INPUT(base, mask) ((*(base+1)) &= ~(mask)) |
|
|
60 |
#define DIRECT_MODE_OUTPUT(base, mask) ((*(base+1)) |= (mask)) |
|
|
61 |
#define DIRECT_WRITE_LOW(base, mask) ((*(base+2)) &= ~(mask)) |
|
|
62 |
#define DIRECT_WRITE_HIGH(base, mask) ((*(base+2)) |= (mask)) |
|
|
63 |
|
|
|
64 |
#elif defined(__PIC32MX__) |
|
|
65 |
#include <plib.h> // is this necessary? |
|
|
66 |
#define PIN_TO_BASEREG(pin) (portModeRegister(digitalPinToPort(pin))) |
|
|
67 |
#define PIN_TO_BITMASK(pin) (digitalPinToBitMask(pin)) |
|
|
68 |
#define IO_REG_TYPE uint32_t |
|
|
69 |
#define IO_REG_ASM |
|
|
70 |
#define DIRECT_READ(base, mask) (((*(base+4)) & (mask)) ? 1 : 0) //PORTX + 0x10 |
|
|
71 |
#define DIRECT_MODE_INPUT(base, mask) ((*(base+2)) = (mask)) //TRISXSET + 0x08 |
|
|
72 |
#define DIRECT_MODE_OUTPUT(base, mask) ((*(base+1)) = (mask)) //TRISXCLR + 0x04 |
|
|
73 |
#define DIRECT_WRITE_LOW(base, mask) ((*(base+8+1)) = (mask)) //LATXCLR + 0x24 |
|
|
74 |
#define DIRECT_WRITE_HIGH(base, mask) ((*(base+8+2)) = (mask)) //LATXSET + 0x28 |
|
|
75 |
|
|
|
76 |
#else |
|
|
77 |
#error "Please define I/O register types here" |
|
|
78 |
#endif |
|
|
79 |
|
|
|
80 |
|
|
|
81 |
class OneWire |
|
|
82 |
{ |
|
|
83 |
private: |
|
|
84 |
IO_REG_TYPE bitmask; |
|
|
85 |
volatile IO_REG_TYPE *baseReg; |
|
|
86 |
|
|
|
87 |
#if ONEWIRE_SEARCH |
|
|
88 |
// global search state |
|
|
89 |
unsigned char ROM_NO[8]; |
|
|
90 |
uint8_t LastDiscrepancy; |
|
|
91 |
uint8_t LastFamilyDiscrepancy; |
|
|
92 |
uint8_t LastDeviceFlag; |
|
|
93 |
#endif |
|
|
94 |
|
|
|
95 |
public: |
|
|
96 |
OneWire( uint8_t pin); |
|
|
97 |
|
|
|
98 |
// Perform a 1-Wire reset cycle. Returns 1 if a device responds |
|
|
99 |
// with a presence pulse. Returns 0 if there is no device or the |
|
|
100 |
// bus is shorted or otherwise held low for more than 250uS |
|
|
101 |
uint8_t reset(void); |
|
|
102 |
|
|
|
103 |
// Issue a 1-Wire rom select command, you do the reset first. |
|
|
104 |
void select( uint8_t rom[8]); |
|
|
105 |
|
|
|
106 |
// Issue a 1-Wire rom skip command, to address all on bus. |
|
|
107 |
void skip(void); |
|
|
108 |
|
|
|
109 |
// Write a byte. If 'power' is one then the wire is held high at |
|
|
110 |
// the end for parasitically powered devices. You are responsible |
|
|
111 |
// for eventually depowering it by calling depower() or doing |
|
|
112 |
// another read or write. |
|
|
113 |
void write(uint8_t v, uint8_t power = 0); |
|
|
114 |
|
|
|
115 |
void write_bytes(const uint8_t *buf, uint16_t count, bool power = 0); |
|
|
116 |
|
|
|
117 |
// Read a byte. |
|
|
118 |
uint8_t read(void); |
|
|
119 |
|
|
|
120 |
void read_bytes(uint8_t *buf, uint16_t count); |
|
|
121 |
|
|
|
122 |
// Write a bit. The bus is always left powered at the end, see |
|
|
123 |
// note in write() about that. |
|
|
124 |
void write_bit(uint8_t v); |
|
|
125 |
|
|
|
126 |
// Read a bit. |
|
|
127 |
uint8_t read_bit(void); |
|
|
128 |
|
|
|
129 |
// Stop forcing power onto the bus. You only need to do this if |
|
|
130 |
// you used the 'power' flag to write() or used a write_bit() call |
|
|
131 |
// and aren't about to do another read or write. You would rather |
|
|
132 |
// not leave this powered if you don't have to, just in case |
|
|
133 |
// someone shorts your bus. |
|
|
134 |
void depower(void); |
|
|
135 |
|
|
|
136 |
#if ONEWIRE_SEARCH |
|
|
137 |
// Clear the search state so that if will start from the beginning again. |
|
|
138 |
void reset_search(); |
|
|
139 |
|
|
|
140 |
// Look for the next device. Returns 1 if a new address has been |
|
|
141 |
// returned. A zero might mean that the bus is shorted, there are |
|
|
142 |
// no devices, or you have already retrieved all of them. It |
|
|
143 |
// might be a good idea to check the CRC to make sure you didn't |
|
|
144 |
// get garbage. The order is deterministic. You will always get |
|
|
145 |
// the same devices in the same order. |
|
|
146 |
uint8_t search(uint8_t *newAddr); |
|
|
147 |
#endif |
|
|
148 |
|
|
|
149 |
#if ONEWIRE_CRC |
|
|
150 |
// Compute a Dallas Semiconductor 8 bit CRC, these are used in the |
|
|
151 |
// ROM and scratchpad registers. |
|
|
152 |
static uint8_t crc8( uint8_t *addr, uint8_t len); |
|
|
153 |
|
|
|
154 |
#if ONEWIRE_CRC16 |
|
|
155 |
// Compute the 1-Wire CRC16 and compare it against the received CRC. |
|
|
156 |
// Example usage (reading a DS2408): |
|
|
157 |
// // Put everything in a buffer so we can compute the CRC easily. |
|
|
158 |
// uint8_t buf[13]; |
|
|
159 |
// buf[0] = 0xF0; // Read PIO Registers |
|
|
160 |
// buf[1] = 0x88; // LSB address |
|
|
161 |
// buf[2] = 0x00; // MSB address |
|
|
162 |
// WriteBytes(net, buf, 3); // Write 3 cmd bytes |
|
|
163 |
// ReadBytes(net, buf+3, 10); // Read 6 data bytes, 2 0xFF, 2 CRC16 |
|
|
164 |
// if (!CheckCRC16(buf, 11, &buf[11])) { |
|
|
165 |
// // Handle error. |
|
|
166 |
// } |
|
|
167 |
// |
|
|
168 |
// @param input - Array of bytes to checksum. |
|
|
169 |
// @param len - How many bytes to use. |
|
|
170 |
// @param inverted_crc - The two CRC16 bytes in the received data. |
|
|
171 |
// This should just point into the received data, |
|
|
172 |
// *not* at a 16-bit integer. |
|
|
173 |
// @return True, iff the CRC matches. |
|
|
174 |
static bool check_crc16(uint8_t* input, uint16_t len, uint8_t* inverted_crc); |
|
|
175 |
|
|
|
176 |
// Compute a Dallas Semiconductor 16 bit CRC. This is required to check |
|
|
177 |
// the integrity of data received from many 1-Wire devices. Note that the |
|
|
178 |
// CRC computed here is *not* what you'll get from the 1-Wire network, |
|
|
179 |
// for two reasons: |
|
|
180 |
// 1) The CRC is transmitted bitwise inverted. |
|
|
181 |
// 2) Depending on the endian-ness of your processor, the binary |
|
|
182 |
// representation of the two-byte return value may have a different |
|
|
183 |
// byte order than the two bytes you get from 1-Wire. |
|
|
184 |
// @param input - Array of bytes to checksum. |
|
|
185 |
// @param len - How many bytes to use. |
|
|
186 |
// @return The CRC16, as defined by Dallas Semiconductor. |
|
|
187 |
static uint16_t crc16(uint8_t* input, uint16_t len); |
|
|
188 |
#endif |
|
|
189 |
#endif |
|
|
190 |
}; |
|
|
191 |
|
|
|
192 |
#endif |