3 * Copyright (C) 2009 Eric Reed
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.
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.
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
20 * Eric Reed <ericr at reedhome.net>
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
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
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.
40 #include "configfile.h"
42 #if HAVE_TERMIOS_H && HAVE_SYS_IOCTL_H && HAVE_MATH_H
44 # include <sys/ioctl.h>
47 # error "No applicable input method."
50 #define EXPECTED_PACKAGE_LENGTH 278
52 #define PKT_BEGIN 0x04
55 #define DEFAULT_DEVICE "/dev/ttyUSB0"
57 static char *conf_device = NULL;
58 static int conf_retries = 0;
62 static const char *config_keys[] =
67 static int config_keys_num = STATIC_ARRAY_SIZE (config_keys);
69 static int ted_read_value(double *ret_power, double *ret_voltage)
71 unsigned char receive_buffer[300];
72 unsigned char package_buffer[300];
73 unsigned char pkt_request[1] = {0xAA};
74 int package_buffer_pos;
78 /* Initialize timeout structure, set to 2 seconds */
79 struct timeval timeout = {
90 /* Initialize the input set*/
94 /* clear out anything in the buffer */
95 tcflush (fd, TCIFLUSH);
97 status = write (fd, pkt_request, sizeof(pkt_request));
100 ERROR ("ted plugin: swrite failed.");
104 /* Loop until we find the end of the package */
106 package_buffer_pos = 0;
107 while (end_flag == 0)
109 ssize_t receive_buffer_length;
112 /* check for timeout or input error*/
113 status = select (fd + 1, &input, NULL, NULL, &timeout);
114 if (status == 0) /* Timeout */
116 WARNING ("ted plugin: Timeout while waiting for file descriptor "
120 else if ((status < 0) && ((errno == EAGAIN) || (errno == EINTR)))
122 /* Some signal or something. Start over.. */
128 ERROR ("ted plugin: select failed: %s",
129 sstrerror (errno, errbuf, sizeof (errbuf)));
133 receive_buffer_length = read (fd, receive_buffer, sizeof (receive_buffer));
134 if (receive_buffer_length < 0)
137 if ((errno == EAGAIN) || (errno == EINTR))
139 ERROR ("ted plugin: read(2) failed: %s",
140 sstrerror (errno, errbuf, sizeof (errbuf)));
143 else if (receive_buffer_length == 0)
145 /* Should we close the FD in this case? */
146 WARNING ("ted plugin: Received EOF from file descriptor.");
149 else if (((size_t) receive_buffer_length) > sizeof (receive_buffer))
151 ERROR ("ted plugin: read(2) returned invalid value %zi.",
152 receive_buffer_length);
159 * Handle escape sequences in `receive_buffer' and put the
160 * result in `package_buffer'.
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. */
167 for (i = 0; i < receive_buffer_length; i++)
169 /* Check if previous byte was the escape byte. */
170 if (escape_flag == 1)
173 /* escape escape = single escape */
174 if ((receive_buffer[i] == ESCAPE)
175 && (package_buffer_pos >= 0))
177 package_buffer[package_buffer_pos] = ESCAPE;
178 package_buffer_pos++;
180 else if (receive_buffer[i] == PKT_BEGIN)
182 package_buffer_pos = 0;
184 else if (receive_buffer[i] == PKT_END)
191 DEBUG ("ted plugin: Unknown escaped byte: %#x",
192 (unsigned int) receive_buffer[i]);
195 else if (receive_buffer[i] == ESCAPE)
199 /* if we are in a package add byte to buffer
200 * otherwise throw away */
201 else if (package_buffer_pos >= 0)
203 package_buffer[package_buffer_pos] = receive_buffer[i];
204 package_buffer_pos++;
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))
214 * Power is at positions 247 and 248 (LSB first) in [10kW].
215 * Voltage is at positions 251 and 252 (LSB first) in [.1V].
217 * Power is in 10 Watt steps
218 * Voltage is in volts
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]));
227 } /* int ted_read_value */
229 static int ted_open_device (void)
232 struct termios options;
237 dev = DEFAULT_DEVICE;
238 if (conf_device != NULL)
241 fd = open (dev, O_RDWR | O_NOCTTY | O_NDELAY | O_NONBLOCK);
244 ERROR ("ted plugin: Unable to open device %s.", dev);
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;
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);
263 } /* int ted_open_device */
265 static void ted_submit (const char *type, double value)
268 value_list_t vl = VALUE_LIST_INIT;
270 values[0].gauge = value;
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);
281 static int ted_config (const char *key, const char *value)
283 if (strcasecmp ("Device", key) == 0)
286 conf_device = sstrdup (value);
288 else if (strcasecmp ("Retries", key) == 0)
295 WARNING ("ted plugin: Invalid retry count: %i", tmp);
302 ERROR ("ted plugin: Unknown config option: %s", key);
307 } /* int ted_config */
309 static int ted_read (void)
316 status = ted_open_device ();
322 for (i = 0; i <= conf_retries; i++)
324 status = ted_read_value (&power, &voltage);
332 ted_submit ("power", power);
333 ted_submit ("voltage", voltage);
338 static int ted_shutdown (void)
347 } /* int ted_shutdown */
349 void module_register (void)
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 : */