1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
|
#ifndef OneWire_h
#define OneWire_h
#include <inttypes.h>
#include <stdbool.h>
#include <avr/pgmspace.h>
// You can exclude certain features from OneWire. In theory, this
// might save some space. In practice, the compiler automatically
// removes unused code (technically, the linker, using -fdata-sections
// and -ffunction-sections when compiling, and Wl,--gc-sections
// when linking), so most of these will not result in any code size
// reduction. Well, unless you try to use the missing features
// and redesign your program to not need them! ONEWIRE_CRC8_TABLE
// is the exception, because it selects a fast but large algorithm
// or a small but slow algorithm.
// you can exclude onewire_search by defining that to 0
#ifndef ONEWIRE_SEARCH
#define ONEWIRE_SEARCH 1
#endif
// You can exclude CRC checks altogether by defining this to 0
#ifndef ONEWIRE_CRC
#define ONEWIRE_CRC 1
#endif
// Select the table-lookup method of computing the 8-bit CRC
// by setting this to 1. The lookup table enlarges code size by
// about 250 bytes. It does NOT consume RAM (but did in very
// old versions of OneWire). If you disable this, a slower
// but very compact algorithm is used.
#ifndef ONEWIRE_CRC8_TABLE
#define ONEWIRE_CRC8_TABLE 1
#endif
// You can allow 16-bit CRC checks by defining this to 1
// (Note that ONEWIRE_CRC must also be 1.)
#ifndef ONEWIRE_CRC16
#define ONEWIRE_CRC16 1
#endif
#define FALSE 0
#define TRUE 1
// Platform specific I/O definitions
#if defined(__AVR__)
#define PIN_TO_BASEREG(pin) (portInputRegister(digitalPinToPort(pin)))
#define PIN_TO_BITMASK(pin) (digitalPinToBitMask(pin))
#define IO_REG_TYPE uint8_t
#define IO_REG_ASM __asm__("r30")
#define DIRECT_READ(base, mask) (((*(base)) & (mask)) ? 1 : 0)
#define DIRECT_MODE_INPUT(base, mask) ((*((base)+1)) &= ~(mask))
#define DIRECT_MODE_OUTPUT(base, mask) ((*((base)+1)) |= (mask))
#define DIRECT_WRITE_LOW(base, mask) ((*((base)+2)) &= ~(mask))
#define DIRECT_WRITE_HIGH(base, mask) ((*((base)+2)) |= (mask))
#elif defined(__MK20DX128__)
#define PIN_TO_BASEREG(pin) (portOutputRegister(pin))
#define PIN_TO_BITMASK(pin) (1)
#define IO_REG_TYPE uint8_t
#define IO_REG_ASM
#define DIRECT_READ(base, mask) (*((base)+512))
#define DIRECT_MODE_INPUT(base, mask) (*((base)+640) = 0)
#define DIRECT_MODE_OUTPUT(base, mask) (*((base)+640) = 1)
#define DIRECT_WRITE_LOW(base, mask) (*((base)+256) = 1)
#define DIRECT_WRITE_HIGH(base, mask) (*((base)+128) = 1)
#elif defined(__SAM3X8E__)
// Arduino 1.5.1 may have a bug in delayMicroseconds() on Arduino Due.
// http://arduino.cc/forum/index.php/topic,141030.msg1076268.html#msg1076268
// If you have trouble with OneWire on Arduino Due, please check the
// status of delayMicroseconds() before reporting a bug in OneWire!
#define PIN_TO_BASEREG(pin) (&(digitalPinToPort(pin)->PIO_PER))
#define PIN_TO_BITMASK(pin) (digitalPinToBitMask(pin))
#define IO_REG_TYPE uint32_t
#define IO_REG_ASM
#define DIRECT_READ(base, mask) (((*((base)+15)) & (mask)) ? 1 : 0)
#define DIRECT_MODE_INPUT(base, mask) ((*((base)+5)) = (mask))
#define DIRECT_MODE_OUTPUT(base, mask) ((*((base)+4)) = (mask))
#define DIRECT_WRITE_LOW(base, mask) ((*((base)+13)) = (mask))
#define DIRECT_WRITE_HIGH(base, mask) ((*((base)+12)) = (mask))
#ifndef PROGMEM
#define PROGMEM
#endif
#ifndef pgm_read_byte
#define pgm_read_byte(addr) (*(const uint8_t *)(addr))
#endif
#elif defined(__PIC32MX__)
#define PIN_TO_BASEREG(pin) (portModeRegister(digitalPinToPort(pin)))
#define PIN_TO_BITMASK(pin) (digitalPinToBitMask(pin))
#define IO_REG_TYPE uint32_t
#define IO_REG_ASM
#define DIRECT_READ(base, mask) (((*(base+4)) & (mask)) ? 1 : 0) //PORTX + 0x10
#define DIRECT_MODE_INPUT(base, mask) ((*(base+2)) = (mask)) //TRISXSET + 0x08
#define DIRECT_MODE_OUTPUT(base, mask) ((*(base+1)) = (mask)) //TRISXCLR + 0x04
#define DIRECT_WRITE_LOW(base, mask) ((*(base+8+1)) = (mask)) //LATXCLR + 0x24
#define DIRECT_WRITE_HIGH(base, mask) ((*(base+8+2)) = (mask)) //LATXSET + 0x28
#else
#error "Please define I/O register types here"
#endif
#ifndef _BV
#define _BV(bit) (1 << (bit))
#endif
void owi_init(uint8_t pin, volatile IO_REG_TYPE *pin_read_port);
uint8_t owi_reset(void);
void owi_select(const uint8_t rom[8]);
// Issue a 1-Wire rom skip command, to address all on bus.
void owi_skip(void);
// Write a byte. If 'power' is one then the wire is held high at
// the end for parasitically powered devices. You are responsible
// for eventually depowering it by calling depower() or doing
// another read or write.
void owi_write(uint8_t v, uint8_t power);
void owi_write_bytes(const uint8_t *buf, uint16_t count, bool power);
// Read a byte.
uint8_t owi_read(void);
void owi_read_bytes(uint8_t *buf, uint16_t count);
// Write a bit. The bus is always left powered at the end, see
// note in write() about that.
void owi_write_bit(uint8_t v);
// Read a bit.
uint8_t owi_read_bit(void);
// Stop forcing power onto the bus. You only need to do this if
// you used the 'power' flag to write() or used a write_bit() call
// and aren't about to do another read or write. You would rather
// not leave this powered if you don't have to, just in case
// someone shorts your bus.
void owi_depower(void);
#if ONEWIRE_SEARCH
// Clear the search state so that if will start from the beginning again.
void owi_reset_search(void);
// Setup the search to find the device type 'family_code' on the next call
// to search(*newAddr) if it is present.
void owi_target_search(uint8_t family_code);
// Look for the next device. Returns 1 if a new address has been
// returned. A zero might mean that the bus is shorted, there are
// no devices, or you have already retrieved all of them. It
// might be a good idea to check the CRC to make sure you didn't
// get garbage. The order is deterministic. You will always get
// the same devices in the same order.
uint8_t owi_search(uint8_t *newAddr);
#endif
#if ONEWIRE_CRC
// Compute a Dallas Semiconductor 8 bit CRC, these are used in the
// ROM and scratchpad registers.
uint8_t owi_crc8(const uint8_t *addr, uint8_t len);
#if ONEWIRE_CRC16
// Compute the 1-Wire CRC16 and compare it against the received CRC.
// Example usage (reading a DS2408):
// // Put everything in a buffer so we can compute the CRC easily.
// uint8_t buf[13];
// buf[0] = 0xF0; // Read PIO Registers
// buf[1] = 0x88; // LSB address
// buf[2] = 0x00; // MSB address
// WriteBytes(net, buf, 3); // Write 3 cmd bytes
// ReadBytes(net, buf+3, 10); // Read 6 data bytes, 2 0xFF, 2 CRC16
// if (!CheckCRC16(buf, 11, &buf[11])) {
// // Handle error.
// }
//
// @param input - Array of bytes to checksum.
// @param len - How many bytes to use.
// @param inverted_crc - The two CRC16 bytes in the received data.
// This should just point into the received data,
// *not* at a 16-bit integer.
// @param crc - The crc starting value (optional)
// @return True, iff the CRC matches.
bool owi_check_crc16(const uint8_t* input, uint16_t len, const uint8_t* inverted_crc, uint16_t crc);
// Compute a Dallas Semiconductor 16 bit CRC. This is required to check
// the integrity of data received from many 1-Wire devices. Note that the
// CRC computed here is *not* what you'll get from the 1-Wire network,
// for two reasons:
// 1) The CRC is transmitted bitwise inverted.
// 2) Depending on the endian-ness of your processor, the binary
// representation of the two-byte return value may have a different
// byte order than the two bytes you get from 1-Wire.
// @param input - Array of bytes to checksum.
// @param len - How many bytes to use.
// @param crc - The crc starting value (optional)
// @return The CRC16, as defined by Dallas Semiconductor.
uint16_t owi_crc16(const uint8_t* input, uint16_t len, uint16_t crc);
#endif
#endif
#endif
|
