mash/sensors.c

changeset 538
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parent 537
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child 539
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equal deleted inserted replaced
537:4eebab50993e 538:6d139c21e22c
1 /*****************************************************************************
2 * Copyright (C) 2014
3 *
4 * Michiel Broek <mbroek at mbse dot eu>
5 *
6 * This file is part of the mbsePi-apps
7 *
8 * This is free software; you can redistribute it and/or modify it
9 * under the terms of the GNU General Public License as published by the
10 * Free Software Foundation; either version 2, or (at your option) any
11 * later version.
12 *
13 * mbsePi-apps is distributed in the hope that it will be useful, but
14 * WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with EC-65K; see the file COPYING. If not, write to the Free
20 * Software Foundation, 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
21 *****************************************************************************/
22
23 #include "mash.h"
24 #include "xutil.h"
25
26
27 #ifdef HAVE_WIRINGPI_H
28
29 /* wiringPi */
30 #include <wiringPi.h>
31 #include <pcf8574.h>
32 #include <lcd.h>
33
34 extern int debug;
35 extern sys_config Config;
36 extern int my_shutdown;
37
38
39
40 PI_THREAD (my_sensors_loop)
41 {
42 w1_therm *tmp1, *old1;
43 char *device, line[60], *p = NULL;
44 FILE *fp;
45 int temp, rc, deviation;
46
47 syslog(LOG_NOTICE, "Thread my_sensors_loop started");
48 if (debug)
49 fprintf(stdout, "Thread my_sensors_loop started\n");
50
51 /*
52 * Loop forever until the external shutdown variable is set.
53 */
54 for (;;) {
55 /*
56 * Here send our 1-wire sensors values
57 */
58 for (tmp1 = Config.w1therms; tmp1; tmp1 = old1) {
59 old1 = tmp1->next;
60
61 if (my_shutdown) {
62 syslog(LOG_NOTICE, "Thread my_sensors_loop stopped");
63 if (debug)
64 fprintf(stdout, "Thread my_sensors_loop stopped\n");
65 return 0;
66 }
67
68 /*
69 * Build path to the on-wire sensor
70 */
71 device = xstrcpy((char *)"/sys/bus/w1/devices/");
72 device = xstrcat(device, tmp1->master);
73 device = xstrcat(device, (char *)"/");
74 device = xstrcat(device, tmp1->name);
75 device = xstrcat(device, (char *)"/w1_slave");
76
77 /*
78 * Read sensor data
79 */
80 if ((fp = fopen(device, "r"))) {
81 /*
82 * The output looks like:
83 * 72 01 4b 46 7f ff 0e 10 57 : crc=57 YES
84 * 72 01 4b 46 7f ff 0e 10 57 t=23125
85 */
86 fgets(line, 50, fp);
87 line[strlen(line)-1] = '\0';
88 if ((line[36] == 'Y') && (line[37] == 'E')) {
89 /*
90 * CRC is Ok, continue
91 */
92 fgets(line, 50, fp);
93 line[strlen(line)-1] = '\0';
94 strtok(line, (char *)"=");
95 p = strtok(NULL, (char *)"=");
96 rc = sscanf(p, "%d", &temp);
97 if ((rc == 1) && (tmp1->lastval != temp)) {
98 /*
99 * It is possible to have read errors or extreme values.
100 * This can happen with bad connections so we compare the
101 * value with the previous one. If the difference is too
102 * much, we don't send that value. That also means that if
103 * the next value is ok again, it will be marked invalid too.
104 * Maximum error is 20 degrees for now.
105 */
106 deviation = 20000;
107 if ( (tmp1->lastval == 0) ||
108 (tmp1->lastval && (temp > (tmp1->lastval - deviation)) && (temp < (tmp1->lastval + deviation))) ) {
109 /*
110 * Temperature is changed and valid, set flag.
111 */
112 tmp1->update = TRUE;
113 } else {
114 syslog(LOG_NOTICE, "deviation error deviation=%d, old=%d new=%d", deviation, tmp1->lastval, temp);
115 if (debug) {
116 fprintf(stdout, "deviation error deviation=%d, old=%d new=%d\n", deviation, tmp1->lastval, temp);
117 }
118 }
119 tmp1->lastval = temp;
120 }
121 } else {
122 syslog(LOG_NOTICE, "sensor %s/%s CRC error", tmp1->master, tmp1->name);
123 }
124 fclose(fp);
125 tmp1->present = 1;
126 } else {
127 tmp1->present = 0;
128 if (debug)
129 printf("sensor %s is missing\n", tmp1->name);
130 }
131
132 free(device);
133 device = NULL;
134 }
135 }
136 }
137
138
139
140 #endif

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