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comparison 1wire.c @ 12:4b141cc7cbd4

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- Reduce type widths where possible. - Add URL for Dallas OWPD kit. - Hide more stuff behind OW_DEBUG.
author darius
date Wed, 01 Sep 2004 17:45:24 +0930
parents eb1faf51968e
children 026dc24d85e0
comparison
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11:ccc39c9f320b 12:4b141cc7cbd4
1 /* 1 /*
2 * Various 1 wire routines 2 * Various 1 wire routines
3 * Search routine is copied from the Dallas owpd library with mods. 3 * Search routine is copied from the Dallas owpd library with mods
4 * available from here http://www.ibutton.com/software/1wire/wirekit.html
4 * 5 *
5 * $Id$ 6 * $Id$
6 * 7 *
7 * Copyright (c) 2004 8 * Copyright (c) 2004
8 * Daniel O'Connor <darius@dons.net.au>. All rights reserved. 9 * Daniel O'Connor <darius@dons.net.au>. All rights reserved.
34 #include <avr/pgmspace.h> 35 #include <avr/pgmspace.h>
35 36
36 #include "1wire.h" 37 #include "1wire.h"
37 #include "1wire-delay.h" 38 #include "1wire-delay.h"
38 39
40 #if OW_DEBUG
39 void uart_putsP(const char *addr); 41 void uart_putsP(const char *addr);
40 void uart_puts(const char *addr); 42 void uart_puts(const char *addr);
41 void uart_getc(); 43 void uart_getc();
42 int uart_putc(char c); 44 int uart_putc(char c);
45 #endif
43 46
44 static uint8_t OW_LastDevice = 0; 47 static uint8_t OW_LastDevice = 0;
45 static uint8_t OW_LastDiscrepancy = 0; 48 static uint8_t OW_LastDiscrepancy = 0;
46 static uint8_t OW_LastFamilyDiscrepancy = 0; 49 static uint8_t OW_LastFamilyDiscrepancy = 0;
47 50
49 OWdelay(void) { 52 OWdelay(void) {
50 DELAY_I; 53 DELAY_I;
51 } 54 }
52 55
53 /*----------------------------------------------------------------------------- 56 /*-----------------------------------------------------------------------------
54 * Generate a 1-Wire reset, return 1 if no presence detect was found, 57 * Generate a 1-Wire reset, return 0 if presence pulse was found,
55 * return 0 otherwise. 58 * return 1 otherwise.
56 * (NOTE: Does not handle alarm presence from DS2404/DS1994) 59 * (NOTE: Does not handle alarm presence from DS2404/DS1994)
57 */ 60 */
58 int 61 uint8_t
59 OWTouchReset(void) { 62 OWTouchReset(void) {
60 DELAY_G; 63 DELAY_G;
61 OWIREOUTPORT &= ~(_BV(OWIREOUTPIN)); 64 OWIREOUTPORT &= ~(_BV(OWIREOUTPIN));
62 OWIREDDR |= _BV(OWIREOUTPIN); 65 OWIREDDR |= _BV(OWIREOUTPIN);
63 DELAY_H; 66 DELAY_H;
69 72
70 /*----------------------------------------------------------------------------- 73 /*-----------------------------------------------------------------------------
71 * Send a 1-wire write bit. 74 * Send a 1-wire write bit.
72 */ 75 */
73 void 76 void
74 OWWriteBit(int bit) { 77 OWWriteBit(uint8_t bit) {
75 OWdelay(); 78 OWdelay();
76 if (bit) { 79 if (bit) {
77 OWIREOUTPORT &= ~(_BV(OWIREOUTPIN)); 80 OWIREOUTPORT &= ~(_BV(OWIREOUTPIN));
78 OWIREDDR |= _BV(OWIREOUTPIN); 81 OWIREDDR |= _BV(OWIREOUTPIN);
79 DELAY_A; 82 DELAY_A;
89 } 92 }
90 93
91 /*----------------------------------------------------------------------------- 94 /*-----------------------------------------------------------------------------
92 * Read a bit from the 1-wire bus and return it. 95 * Read a bit from the 1-wire bus and return it.
93 */ 96 */
94 int 97 uint8_t
95 OWReadBit(void) { 98 OWReadBit(void) {
96 OWdelay(); 99 OWdelay();
97 100
98 OWIREOUTPORT &= ~(_BV(OWIREOUTPIN)); 101 OWIREOUTPORT &= ~(_BV(OWIREOUTPIN));
99 OWIREDDR |= _BV(OWIREOUTPIN); 102 OWIREDDR |= _BV(OWIREOUTPIN);
106 /*----------------------------------------------------------------------------- 109 /*-----------------------------------------------------------------------------
107 * Write a byte to the 1-wire bus 110 * Write a byte to the 1-wire bus
108 */ 111 */
109 void 112 void
110 OWWriteByte(uint8_t data) { 113 OWWriteByte(uint8_t data) {
111 int i; 114 uint8_t i;
112 115
113 /* Send LSB first */ 116 /* Send LSB first */
114 for (i = 0; i < 8; i++) { 117 for (i = 0; i < 8; i++) {
115 OWWriteBit(data & 0x01); 118 OWWriteBit(data & 0x01);
116 data >>= 1; 119 data >>= 1;
118 } 121 }
119 122
120 /*----------------------------------------------------------------------------- 123 /*-----------------------------------------------------------------------------
121 * Read a byte from the 1-wire bus 124 * Read a byte from the 1-wire bus
122 */ 125 */
123 int 126 uint8_t
124 OWReadByte(void) { 127 OWReadByte(void) {
125 int i, result = 0; 128 int i, result = 0;
126 129
127 for (i = 0; i < 8; i++) { 130 for (i = 0; i < 8; i++) {
128 result >>= 1; 131 result >>= 1;
133 } 136 }
134 137
135 /*----------------------------------------------------------------------------- 138 /*-----------------------------------------------------------------------------
136 * Write a 1-wire data byte and return the sampled result. 139 * Write a 1-wire data byte and return the sampled result.
137 */ 140 */
138 int 141 uint8_t
139 OWTouchByte(uint8_t data) { 142 OWTouchByte(uint8_t data) {
140 int i, result = 0; 143 uint8_t i, result = 0;
141 144
142 for (i = 0; i < 8; i++) { 145 for (i = 0; i < 8; i++) {
143 result >>= 1; 146 result >>= 1;
144 147
145 /* If sending a 1 then read a bit, otherwise write a 0 */ 148 /* If sending a 1 then read a bit, otherwise write a 0 */
171 /*----------------------------------------------------------------------------- 174 /*-----------------------------------------------------------------------------
172 * Send a 1 wire command to a device, or all if no ROM ID provided 175 * Send a 1 wire command to a device, or all if no ROM ID provided
173 */ 176 */
174 void 177 void
175 OWSendCmd(uint8_t *ROM, uint8_t cmd) { 178 OWSendCmd(uint8_t *ROM, uint8_t cmd) {
176 int i; 179 uint8_t i;
177 180
178 OWTouchReset(); 181 OWTouchReset();
179 182
180 if (ROM == NULL) 183 if (ROM == NULL)
181 OWWriteByte(OW_SKIP_ROM_CMD); 184 OWWriteByte(OW_SKIP_ROM_CMD);
196 * 0 no more modules 199 * 0 no more modules
197 * -1 if no presense pulse, 200 * -1 if no presense pulse,
198 * -2 if bad CRC, 201 * -2 if bad CRC,
199 * -3 if bad wiring. 202 * -3 if bad wiring.
200 */ 203 */
201 int 204 uint8_t
202 OWFirst(uint8_t *ROM, uint8_t do_reset, uint8_t alarm_only) { 205 OWFirst(uint8_t *ROM, uint8_t do_reset, uint8_t alarm_only) {
203 /* Reset state */ 206 /* Reset state */
204 OW_LastDiscrepancy = 0; 207 OW_LastDiscrepancy = 0;
205 OW_LastDevice = 0; 208 OW_LastDevice = 0;
206 OW_LastFamilyDiscrepancy = 0; 209 OW_LastFamilyDiscrepancy = 0;
208 /* Go looking */ 211 /* Go looking */
209 return (OWNext(ROM, do_reset, alarm_only)); 212 return (OWNext(ROM, do_reset, alarm_only));
210 } 213 }
211 214
212 /* Returns 1 when something is found, 0 if nothing left */ 215 /* Returns 1 when something is found, 0 if nothing left */
213 int 216 uint8_t
214 OWNext(uint8_t *ROM, uint8_t do_reset, uint8_t alarm_only) { 217 OWNext(uint8_t *ROM, uint8_t do_reset, uint8_t alarm_only) {
215 uint8_t bit_test, search_direction, bit_number; 218 uint8_t bit_test, search_direction, bit_number;
216 uint8_t last_zero, rom_byte_number, rom_byte_mask; 219 uint8_t last_zero, rom_byte_number, rom_byte_mask;
217 uint8_t lastcrc8, crcaccum; 220 uint8_t lastcrc8, crcaccum;
218 int next_result; 221 int8_t next_result;
219 char errstr[30];
220 222
221 /* Init for search */ 223 /* Init for search */
222 bit_number = 1; 224 bit_number = 1;
223 last_zero = 0; 225 last_zero = 0;
224 rom_byte_number = 0; 226 rom_byte_number = 0;
328 } while (rom_byte_number < 8); /* loop until through all ROM bytes 0-7 */ 330 } while (rom_byte_number < 8); /* loop until through all ROM bytes 0-7 */
329 331
330 /* if the search was successful then */ 332 /* if the search was successful then */
331 if (!(bit_number < 65) || lastcrc8) { 333 if (!(bit_number < 65) || lastcrc8) {
332 if (lastcrc8) { 334 if (lastcrc8) {
335 #if OW_DEBUG
333 sprintf_P(errstr, PSTR("Bad CRC (%d)\n\r"), lastcrc8); 336 sprintf_P(errstr, PSTR("Bad CRC (%d)\n\r"), lastcrc8);
334 uart_puts(errstr); 337 uart_puts(errstr);
338 #endif
335 next_result = OW_BADCRC; 339 next_result = OW_BADCRC;
336 } else { 340 } else {
337 /* search successful so set LastDiscrepancy,LastDevice,next_result */ 341 /* search successful so set LastDiscrepancy,LastDevice,next_result */
338 OW_LastDiscrepancy = last_zero; 342 OW_LastDiscrepancy = last_zero;
339 OW_LastDevice = (OW_LastDiscrepancy == 0); 343 OW_LastDevice = (OW_LastDiscrepancy == 0);