--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/thermferm/sensors.c Sun May 18 21:24:55 2014 +0200
@@ -0,0 +1,135 @@
+/*****************************************************************************
+ * Copyright (C) 2014
+ *
+ * Michiel Broek <mbroek at mbse dot eu>
+ *
+ * This file is part of the mbsePi-apps
+ *
+ * This is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2, or (at your option) any
+ * later version.
+ *
+ * mbsePi-apps is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with EC-65K; see the file COPYING. If not, write to the Free
+ * Software Foundation, 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
+ *****************************************************************************/
+
+#include "../lib/mbselib.h"
+#include "sensors.h"
+
+#ifdef HAVE_WIRINGPI_H
+
+
+extern bool debug;
+extern sys_config Config;
+extern int my_shutdown;
+
+
+
+PI_THREAD (my_sensors_loop)
+{
+ w1_therm *tmp1, *old1;
+ char *device, line[60], *p = NULL;
+ FILE *fp;
+ int temp, rc, deviation;
+
+ syslog(LOG_NOTICE, "Thread my_sensors_loop started");
+ if (debug)
+ fprintf(stdout, "Thread my_sensors_loop started\n");
+
+ /*
+ * Loop forever until the external shutdown variable is set.
+ */
+ for (;;) {
+ /*
+ * Here send our 1-wire sensors values
+ */
+ for (tmp1 = Config.w1therms; tmp1; tmp1 = old1) {
+ old1 = tmp1->next;
+
+ if (my_shutdown) {
+ syslog(LOG_NOTICE, "Thread my_sensors_loop stopped");
+ if (debug)
+ fprintf(stdout, "Thread my_sensors_loop stopped\n");
+ return 0;
+ }
+
+ /*
+ * Build path to the on-wire sensor
+ */
+ device = xstrcpy((char *)"/sys/bus/w1/devices/");
+ device = xstrcat(device, tmp1->master);
+ device = xstrcat(device, (char *)"/");
+ device = xstrcat(device, tmp1->name);
+ device = xstrcat(device, (char *)"/w1_slave");
+
+ /*
+ * Read sensor data
+ */
+ if ((fp = fopen(device, "r"))) {
+ /*
+ * The output looks like:
+ * 72 01 4b 46 7f ff 0e 10 57 : crc=57 YES
+ * 72 01 4b 46 7f ff 0e 10 57 t=23125
+ */
+ fgets(line, 50, fp);
+ line[strlen(line)-1] = '\0';
+ if ((line[36] == 'Y') && (line[37] == 'E')) {
+ /*
+ * CRC is Ok, continue
+ */
+ fgets(line, 50, fp);
+ line[strlen(line)-1] = '\0';
+ strtok(line, (char *)"=");
+ p = strtok(NULL, (char *)"=");
+ rc = sscanf(p, "%d", &temp);
+ if ((rc == 1) && (tmp1->lastval != temp)) {
+ /*
+ * It is possible to have read errors or extreme values.
+ * This can happen with bad connections so we compare the
+ * value with the previous one. If the difference is too
+ * much, we don't send that value. That also means that if
+ * the next value is ok again, it will be marked invalid too.
+ * Maximum error is 20 degrees for now.
+ */
+ deviation = 20000;
+ if ( (tmp1->lastval == 0) ||
+ (tmp1->lastval && (temp > (tmp1->lastval - deviation)) && (temp < (tmp1->lastval + deviation))) ) {
+ /*
+ * Temperature is changed and valid, set flag.
+ */
+ tmp1->update = TRUE;
+ } else {
+ syslog(LOG_NOTICE, "deviation error deviation=%d, old=%d new=%d", deviation, tmp1->lastval, temp);
+ if (debug) {
+ fprintf(stdout, "deviation error deviation=%d, old=%d new=%d\n", deviation, tmp1->lastval, temp);
+ }
+ }
+ tmp1->lastval = temp;
+ }
+ } else {
+ syslog(LOG_NOTICE, "sensor %s/%s CRC error", tmp1->master, tmp1->name);
+ }
+ fclose(fp);
+ tmp1->present = 1;
+ } else {
+ tmp1->present = 0;
+ if (debug)
+ printf("sensor %s is missing\n", tmp1->name);
+ }
+
+ free(device);
+ device = NULL;
+ }
+ }
+}
+
+
+
+#endif