282212b114f0c1832a4401663825aebf0678715c
1 /**
2 * collectd - src/ted.c
3 * Copyright (C) 2009 Eric Reed
4 *
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License as published by the
7 * Free Software Foundation; either version 2 of the License, or (at your
8 * option) any later version.
9 *
10 * This program is distributed in the hope that it will be useful, but
11 * WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License along
16 * with this program; if not, write to the Free Software Foundation, Inc.,
17 * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
18 *
19 * Authors:
20 * Eric Reed <ericr at reedhome.net>
21 *
22 * This is a collectd module for The Energy Detective: A low-cost whole
23 * house energy monitoring system. For more information on TED, see
24 * http://theenergydetective.com
25 *
26 * This module was not created by Energy, Inc. nor is it supported by
27 * them in any way. It was created using information from two sources:
28 * David Satterfield's TED module for Misterhouse, and Micah Dowty's TED
29 * Python Module.
30 *
31 * This has only tested with the model 1001 RDU, with
32 * firmware version 9.01U. The USB port is uses the very common FTDI
33 * USB-to-serial chip, so the RDU will show up as a serial device on
34 * Windows, Mac OS, or Linux.
35 **/
37 #include "collectd.h"
38 #include "common.h"
39 #include "plugin.h"
40 #include "configfile.h"
42 #if HAVE_TERMIOS_H && HAVE_SYS_IOCTL_H && HAVE_MATH_H
43 # include <termios.h>
44 # include <sys/ioctl.h>
45 # include <math.h>
46 #else
47 # error "No applicable input method."
48 #endif
50 #define EXPECTED_PACKAGE_LENGTH 278
51 #define ESCAPE 0x10
52 #define PKT_BEGIN 0x04
53 #define PKT_END 0x03
55 #define DEFAULT_DEVICE "/dev/ttyUSB0"
57 static char *conf_device = NULL;
58 static int conf_retries = 0;
60 static int fd = -1;
62 static const char *config_keys[] =
63 {
64 "Device",
65 "Retries"
66 };
67 static int config_keys_num = STATIC_ARRAY_SIZE (config_keys);
69 static int ted_read_value(double *ret_power, double *ret_voltage)
70 {
71 unsigned char receive_buffer[300];
72 unsigned char package_buffer[300];
73 unsigned char pkt_request[1] = {0xAA};
74 int package_buffer_pos;
76 fd_set input;
78 /* Initialize timeout structure, set to 2 seconds */
79 struct timeval timeout = {
80 .tv_sec = 2
81 };
83 int end_flag;
84 int escape_flag;
86 int status;
88 assert (fd >= 0);
90 /* Initialize the input set*/
91 FD_ZERO (&input);
92 FD_SET (fd, &input);
94 /* clear out anything in the buffer */
95 tcflush (fd, TCIFLUSH);
97 status = write (fd, pkt_request, sizeof(pkt_request));
98 if (status <= 0)
99 {
100 ERROR ("ted plugin: swrite failed.");
101 return (-1);
102 }
104 /* Loop until we find the end of the package */
105 end_flag = 0;
106 package_buffer_pos = 0;
107 while (end_flag == 0)
108 {
109 ssize_t receive_buffer_length;
110 ssize_t i;
112 /* check for timeout or input error*/
113 status = select (fd + 1, &input, NULL, NULL, &timeout);
114 if (status == 0) /* Timeout */
115 {
116 WARNING ("ted plugin: Timeout while waiting for file descriptor "
117 "to become ready.");
118 return (-1);
119 }
120 else if ((status < 0) && ((errno == EAGAIN) || (errno == EINTR)))
121 {
122 /* Some signal or something. Start over.. */
123 continue;
124 }
125 else if (status < 0)
126 {
127 char errbuf[1024];
128 ERROR ("ted plugin: select failed: %s",
129 sstrerror (errno, errbuf, sizeof (errbuf)));
130 return (-1);
131 }
133 receive_buffer_length = read (fd, receive_buffer, sizeof (receive_buffer));
134 if (receive_buffer_length < 0)
135 {
136 char errbuf[1024];
137 if ((errno == EAGAIN) || (errno == EINTR))
138 continue;
139 ERROR ("ted plugin: read(2) failed: %s",
140 sstrerror (errno, errbuf, sizeof (errbuf)));
141 return (-1);
142 }
143 else if (receive_buffer_length == 0)
144 {
145 /* Should we close the FD in this case? */
146 WARNING ("ted plugin: Received EOF from file descriptor.");
147 return (-1);
148 }
149 else if (((size_t) receive_buffer_length) > sizeof (receive_buffer))
150 {
151 ERROR ("ted plugin: read(2) returned invalid value %zi.",
152 receive_buffer_length);
153 return (-1);
154 }
156 /*
157 * packet filter loop
158 *
159 * Handle escape sequences in `receive_buffer' and put the
160 * result in `package_buffer'.
161 */
162 /* We need to see the begin sequence first. When we receive `ESCAPE
163 * PKT_BEGIN', we set `package_buffer_pos' to zero to signal that
164 * the beginning of the package has been found. */
166 escape_flag = 0;
167 for (i = 0; i < receive_buffer_length; i++)
168 {
169 /* Check if previous byte was the escape byte. */
170 if (escape_flag == 1)
171 {
172 escape_flag = 0;
173 /* escape escape = single escape */
174 if ((receive_buffer[i] == ESCAPE)
175 && (package_buffer_pos >= 0))
176 {
177 package_buffer[package_buffer_pos] = ESCAPE;
178 package_buffer_pos++;
179 }
180 else if (receive_buffer[i] == PKT_BEGIN)
181 {
182 package_buffer_pos = 0;
183 }
184 else if (receive_buffer[i] == PKT_END)
185 {
186 end_flag = 1;
187 break;
188 }
189 else
190 {
191 DEBUG ("ted plugin: Unknown escaped byte: %#x",
192 (unsigned int) receive_buffer[i]);
193 }
194 }
195 else if (receive_buffer[i] == ESCAPE)
196 {
197 escape_flag = 1;
198 }
199 /* if we are in a package add byte to buffer
200 * otherwise throw away */
201 else if (package_buffer_pos >= 0)
202 {
203 package_buffer[package_buffer_pos] = receive_buffer[i];
204 package_buffer_pos++;
205 }
206 } /* for (i = 0; i < receive_buffer_length; i++) */
207 } /* while (end_flag == 0) */
209 /* Check for errors inside the loop. */
210 if ((end_flag == 0) || (package_buffer_pos != EXPECTED_PACKAGE_LENGTH))
211 return (-1);
213 /*
214 * Power is at positions 247 and 248 (LSB first) in [10kW].
215 * Voltage is at positions 251 and 252 (LSB first) in [.1V].
216 *
217 * Power is in 10 Watt steps
218 * Voltage is in volts
219 */
220 *ret_power = 10.0 * (double) ((((int) package_buffer[248]) * 256)
221 + ((int) package_buffer[247]));
222 *ret_voltage = 0.1 * (double) ((((int) package_buffer[252]) * 256)
223 + ((int) package_buffer[251]));
225 /* success */
226 return (0);
227 } /* int ted_read_value */
229 static int ted_open_device (void)
230 {
231 const char *dev;
232 struct termios options;
234 if (fd >= 0)
235 return (0);
237 dev = DEFAULT_DEVICE;
238 if (conf_device != NULL)
239 dev = conf_device;
241 fd = open (dev, O_RDWR | O_NOCTTY | O_NDELAY | O_NONBLOCK);
242 if (fd < 0)
243 {
244 ERROR ("ted plugin: Unable to open device %s.", dev);
245 return (-1);
246 }
248 /* Get the current options for the port... */
249 tcgetattr(fd, &options);
250 options.c_cflag = B19200 | CS8 | CSTOPB | CREAD | CLOCAL;
251 options.c_iflag = IGNBRK | IGNPAR;
252 options.c_oflag = 0;
253 options.c_lflag = 0;
254 options.c_cc[VTIME] = 20;
255 options.c_cc[VMIN] = 250;
257 /* Set the new options for the port... */
258 tcflush(fd, TCIFLUSH);
259 tcsetattr(fd, TCSANOW, &options);
261 INFO ("ted plugin: Successfully opened %s.", dev);
262 return (0);
263 } /* int ted_open_device */
265 static void ted_submit (const char *type, double value)
266 {
267 value_t values[1];
268 value_list_t vl = VALUE_LIST_INIT;
270 values[0].gauge = value;
272 vl.values = values;
273 vl.values_len = 1;
274 sstrncpy (vl.host, hostname_g, sizeof (vl.host));
275 sstrncpy (vl.plugin, "ted", sizeof (vl.plugin));
276 sstrncpy (vl.type, type, sizeof (vl.type));
278 plugin_dispatch_values (&vl);
279 }
281 static int ted_config (const char *key, const char *value)
282 {
283 if (strcasecmp ("Device", key) == 0)
284 {
285 sfree (conf_device);
286 conf_device = sstrdup (value);
287 }
288 else if (strcasecmp ("Retries", key) == 0)
289 {
290 int tmp;
292 tmp = atoi (value);
293 if (tmp < 0)
294 {
295 WARNING ("ted plugin: Invalid retry count: %i", tmp);
296 return (1);
297 }
298 conf_retries = tmp;
299 }
300 else
301 {
302 ERROR ("ted plugin: Unknown config option: %s", key);
303 return (-1);
304 }
306 return (0);
307 } /* int ted_config */
309 static int ted_read (void)
310 {
311 double power;
312 double voltage;
313 int status;
314 int i;
316 status = ted_open_device ();
317 if (status != 0)
318 return (-1);
320 power = NAN;
321 voltage = NAN;
322 for (i = 0; i <= conf_retries; i++)
323 {
324 status = ted_read_value (&power, &voltage);
325 if (status == 0)
326 break;
327 }
329 if (status != 0)
330 return (-1);
332 ted_submit ("power", power);
333 ted_submit ("voltage", voltage);
335 return (0);
336 } /* int ted_read */
338 static int ted_shutdown (void)
339 {
340 if (fd >= 0)
341 {
342 close (fd);
343 fd = -1;
344 }
346 return (0);
347 } /* int ted_shutdown */
349 void module_register (void)
350 {
351 plugin_register_config ("ted", ted_config,
352 config_keys, config_keys_num);
353 plugin_register_read ("ted", ted_read);
354 plugin_register_shutdown ("ted", ted_shutdown);
355 } /* void module_register */
357 /* vim: set sw=4 et : */