]> sigrok.org Git - libsigrok.git/blame - src/dmm/metex14.c
dmm: vc870: support effective voltage & current
[libsigrok.git] / src / dmm / metex14.c
CommitLineData
ac913e5c 1/*
50985c20 2 * This file is part of the libsigrok project.
ac913e5c 3 *
71f1302b 4 * Copyright (C) 2012-2013 Uwe Hermann <uwe@hermann-uwe.de>
ac913e5c
UH
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
19 */
20
e83437ae
MH
21/**
22 * @file
23 *
ac913e5c
UH
24 * Metex 14-bytes ASCII protocol parser.
25 *
e83437ae 26 * @internal
ac913e5c
UH
27 * This should work for various multimeters which use this kind of protocol,
28 * even though there is some variation in which modes each DMM supports.
29 *
30 * It does _not_ work for all Metex DMMs, some use a quite different protocol.
31 */
32
6ec6c43b 33#include <config.h>
ac913e5c 34#include <string.h>
ba464a12 35#include <strings.h>
ac913e5c
UH
36#include <ctype.h>
37#include <math.h>
38#include <glib.h>
c1aae900 39#include <libsigrok/libsigrok.h>
ac913e5c
UH
40#include "libsigrok-internal.h"
41
3544f848 42#define LOG_PREFIX "metex14"
ac913e5c 43
e83437ae
MH
44/** Parse value from buf, byte 2-8. */
45static int parse_value(const uint8_t *buf, struct metex14_info *info,
46 float *result)
ac913e5c 47{
1a807c13
UH
48 int i, is_ol, cnt;
49 char valstr[7 + 1];
50
51 /* Strip all spaces from bytes 2-8. */
52 memset(&valstr, 0, 7 + 1);
53 for (i = 0, cnt = 0; i < 7; i++) {
54 if (buf[2 + i] != ' ')
55 valstr[cnt++] = buf[2 + i];
ac913e5c
UH
56 }
57
58 /* Bytes 5-7: Over limit (various forms) */
59 is_ol = 0;
34577da6
UH
60 is_ol += (!g_ascii_strcasecmp((const char *)&valstr, ".OL")) ? 1 : 0;
61 is_ol += (!g_ascii_strcasecmp((const char *)&valstr, "O.L")) ? 1 : 0;
62 is_ol += (!g_ascii_strcasecmp((const char *)&valstr, "OL.")) ? 1 : 0;
63 is_ol += (!g_ascii_strcasecmp((const char *)&valstr, "OL")) ? 1 : 0;
64 is_ol += (!g_ascii_strcasecmp((const char *)&valstr, "-.OL")) ? 1 : 0;
65 is_ol += (!g_ascii_strcasecmp((const char *)&valstr, "-O.L")) ? 1 : 0;
66 is_ol += (!g_ascii_strcasecmp((const char *)&valstr, "-OL.")) ? 1 : 0;
67 is_ol += (!g_ascii_strcasecmp((const char *)&valstr, "-OL")) ? 1 : 0;
ac913e5c
UH
68 if (is_ol != 0) {
69 sr_spew("Over limit.");
70 *result = INFINITY;
71 return SR_OK;
72 }
73
e83437ae
MH
74 /* Logic functions */
75 if (!strcmp((const char *)&valstr, "READY") ||
76 !strcmp((const char *)&valstr, "FLOAT")) {
77 *result = INFINITY;
78 info->is_logic = TRUE;
79 } else if (!strcmp((const char *)&valstr, "Hi")) {
80 *result = 1.0;
81 info->is_logic = TRUE;
82 } else if (!strcmp((const char *)&valstr, "Lo")) {
83 *result = 0.0;
84 info->is_logic = TRUE;
85 }
86 if (info->is_logic)
87 return SR_OK;
88
1a807c13
UH
89 /* Bytes 2-8: Sign, value (up to 5 digits) and decimal point */
90 sscanf((const char *)&valstr, "%f", result);
ac913e5c 91
1a807c13 92 sr_spew("The display value is %f.", *result);
ac913e5c
UH
93
94 return SR_OK;
95}
96
97static void parse_flags(const char *buf, struct metex14_info *info)
98{
71f1302b
UH
99 int i, cnt;
100 char unit[4 + 1];
101 const char *u;
102
e83437ae
MH
103 /* Bytes 0-1: Measurement mode AC, DC */
104 info->is_ac = !strncmp(buf, "AC", 2);
105 info->is_dc = !strncmp(buf, "DC", 2);
ac913e5c 106
1a807c13 107 /* Bytes 2-8: See parse_value(). */
ac913e5c 108
1a807c13 109 /* Strip all spaces from bytes 9-12. */
71f1302b
UH
110 memset(&unit, 0, 4 + 1);
111 for (i = 0, cnt = 0; i < 4; i++) {
112 if (buf[9 + i] != ' ')
113 unit[cnt++] = buf[9 + i];
114 }
1a807c13
UH
115
116 /* Bytes 9-12: Unit */
71f1302b 117 u = (const char *)&unit;
34577da6 118 if (!g_ascii_strcasecmp(u, "A"))
ac913e5c 119 info->is_ampere = TRUE;
34577da6 120 else if (!g_ascii_strcasecmp(u, "mA"))
ac913e5c 121 info->is_milli = info->is_ampere = TRUE;
34577da6 122 else if (!g_ascii_strcasecmp(u, "uA"))
2477fb95 123 info->is_micro = info->is_ampere = TRUE;
34577da6 124 else if (!g_ascii_strcasecmp(u, "V"))
ac913e5c 125 info->is_volt = TRUE;
34577da6 126 else if (!g_ascii_strcasecmp(u, "mV"))
ac913e5c 127 info->is_milli = info->is_volt = TRUE;
34577da6 128 else if (!g_ascii_strcasecmp(u, "Ohm"))
ac913e5c 129 info->is_ohm = TRUE;
34577da6 130 else if (!g_ascii_strcasecmp(u, "KOhm"))
ac913e5c 131 info->is_kilo = info->is_ohm = TRUE;
34577da6 132 else if (!g_ascii_strcasecmp(u, "MOhm"))
ac913e5c 133 info->is_mega = info->is_ohm = TRUE;
34577da6 134 else if (!g_ascii_strcasecmp(u, "pF"))
c02dc3e2 135 info->is_pico = info->is_farad = TRUE;
34577da6 136 else if (!g_ascii_strcasecmp(u, "nF"))
ac913e5c 137 info->is_nano = info->is_farad = TRUE;
34577da6 138 else if (!g_ascii_strcasecmp(u, "uF"))
ac913e5c 139 info->is_micro = info->is_farad = TRUE;
34577da6 140 else if (!g_ascii_strcasecmp(u, "KHz"))
ac913e5c 141 info->is_kilo = info->is_hertz = TRUE;
34577da6 142 else if (!g_ascii_strcasecmp(u, "C"))
ac913e5c 143 info->is_celsius = TRUE;
34577da6 144 else if (!g_ascii_strcasecmp(u, "DB"))
9871215c 145 info->is_decibel = TRUE;
34577da6 146 else if (!g_ascii_strcasecmp(u, ""))
9871215c 147 info->is_unitless = TRUE;
ac913e5c 148
e83437ae
MH
149 /* Bytes 0-1: Measurement mode, except AC/DC */
150 info->is_resistance = !strncmp(buf, "OH", 2) ||
151 (!strncmp(buf, " ", 2) && info->is_ohm);
152 info->is_capacity = !strncmp(buf, "CA", 2) ||
153 (!strncmp(buf, " ", 2) && info->is_farad);
154 info->is_temperature = !strncmp(buf, "TE", 2);
155 info->is_diode = !strncmp(buf, "DI", 2) ||
156 (!strncmp(buf, " ", 2) && info->is_volt && info->is_milli);
157 info->is_frequency = !strncmp(buf, "FR", 2) ||
158 (!strncmp(buf, " ", 2) && info->is_hertz);
159 info->is_gain = !strncmp(buf, "DB", 2);
160 info->is_hfe = !strncmp(buf, "HF", 2) ||
161 (!strncmp(buf, " ", 2) && !info->is_volt && !info->is_ohm &&
162 !info->is_logic && !info->is_farad && !info->is_hertz);
163 /*
164 * Note:
165 * - Protocol doesn't distinguish "resistance" from "beep" mode.
166 * - "DB" shows the logarithmic ratio of input voltage to a
167 * pre-stored (user-changeable) value in the DMM.
168 */
169
ac913e5c
UH
170 /* Byte 13: Always '\r' (carriage return, 0x0d, 13) */
171}
172
5faebab2 173static void handle_flags(struct sr_datafeed_analog_old *analog, float *floatval,
ac913e5c
UH
174 const struct metex14_info *info)
175{
176 /* Factors */
c02dc3e2
UH
177 if (info->is_pico)
178 *floatval /= 1000000000000ULL;
ac913e5c
UH
179 if (info->is_nano)
180 *floatval /= 1000000000;
181 if (info->is_micro)
182 *floatval /= 1000000;
183 if (info->is_milli)
184 *floatval /= 1000;
185 if (info->is_kilo)
186 *floatval *= 1000;
187 if (info->is_mega)
188 *floatval *= 1000000;
189
190 /* Measurement modes */
191 if (info->is_volt) {
192 analog->mq = SR_MQ_VOLTAGE;
193 analog->unit = SR_UNIT_VOLT;
194 }
195 if (info->is_ampere) {
196 analog->mq = SR_MQ_CURRENT;
197 analog->unit = SR_UNIT_AMPERE;
198 }
199 if (info->is_ohm) {
200 analog->mq = SR_MQ_RESISTANCE;
201 analog->unit = SR_UNIT_OHM;
202 }
203 if (info->is_hertz) {
204 analog->mq = SR_MQ_FREQUENCY;
205 analog->unit = SR_UNIT_HERTZ;
206 }
207 if (info->is_farad) {
208 analog->mq = SR_MQ_CAPACITANCE;
209 analog->unit = SR_UNIT_FARAD;
210 }
211 if (info->is_celsius) {
212 analog->mq = SR_MQ_TEMPERATURE;
213 analog->unit = SR_UNIT_CELSIUS;
214 }
215 if (info->is_diode) {
216 analog->mq = SR_MQ_VOLTAGE;
217 analog->unit = SR_UNIT_VOLT;
218 }
9871215c
UH
219 if (info->is_gain) {
220 analog->mq = SR_MQ_GAIN;
221 analog->unit = SR_UNIT_DECIBEL_VOLT;
222 }
223 if (info->is_hfe) {
224 analog->mq = SR_MQ_GAIN;
225 analog->unit = SR_UNIT_UNITLESS;
226 }
e83437ae
MH
227 if (info->is_logic) {
228 analog->mq = SR_MQ_GAIN;
229 analog->unit = SR_UNIT_UNITLESS;
230 }
ac913e5c
UH
231
232 /* Measurement related flags */
233 if (info->is_ac)
234 analog->mqflags |= SR_MQFLAG_AC;
235 if (info->is_dc)
236 analog->mqflags |= SR_MQFLAG_DC;
a6ed50f4
UH
237 if (info->is_diode)
238 analog->mqflags |= SR_MQFLAG_DIODE;
ac913e5c
UH
239}
240
241static gboolean flags_valid(const struct metex14_info *info)
242{
243 int count;
244
245 /* Does the packet have more than one multiplier? */
246 count = 0;
c02dc3e2 247 count += (info->is_pico) ? 1 : 0;
ac913e5c
UH
248 count += (info->is_nano) ? 1 : 0;
249 count += (info->is_micro) ? 1 : 0;
250 count += (info->is_milli) ? 1 : 0;
251 count += (info->is_kilo) ? 1 : 0;
252 count += (info->is_mega) ? 1 : 0;
253 if (count > 1) {
ec5186f9 254 sr_dbg("More than one multiplier detected in packet.");
ac913e5c
UH
255 return FALSE;
256 }
257
258 /* Does the packet "measure" more than one type of value? */
259 count = 0;
260 count += (info->is_ac) ? 1 : 0;
261 count += (info->is_dc) ? 1 : 0;
262 count += (info->is_resistance) ? 1 : 0;
263 count += (info->is_capacity) ? 1 : 0;
264 count += (info->is_temperature) ? 1 : 0;
265 count += (info->is_diode) ? 1 : 0;
266 count += (info->is_frequency) ? 1 : 0;
267 if (count > 1) {
ec5186f9 268 sr_dbg("More than one measurement type detected in packet.");
ac913e5c
UH
269 return FALSE;
270 }
271
272 /* Both AC and DC set? */
273 if (info->is_ac && info->is_dc) {
ec5186f9 274 sr_dbg("Both AC and DC flags detected in packet.");
ac913e5c
UH
275 return FALSE;
276 }
277
278 return TRUE;
279}
280
c4f2dfd0 281#ifdef HAVE_LIBSERIALPORT
e90cf076
UH
282SR_PRIV int sr_metex14_packet_request(struct sr_serial_dev_inst *serial)
283{
284 const uint8_t wbuf = 'D';
285
286 sr_spew("Requesting DMM packet.");
287
4277ac34 288 return (serial_write_nonblocking(serial, &wbuf, 1) == 1) ? SR_OK : SR_ERR;
e90cf076 289}
c4f2dfd0 290#endif
e90cf076 291
ac913e5c
UH
292SR_PRIV gboolean sr_metex14_packet_valid(const uint8_t *buf)
293{
294 struct metex14_info info;
295
296 memset(&info, 0x00, sizeof(struct metex14_info));
297 parse_flags((const char *)buf, &info);
298
299 if (!flags_valid(&info))
300 return FALSE;
301
302 if (buf[13] != '\r')
303 return FALSE;
304
305 return TRUE;
306}
307
308/**
309 * Parse a protocol packet.
310 *
1fbab466 311 * @param buf Buffer containing the protocol packet. Must not be NULL.
ac913e5c 312 * @param floatval Pointer to a float variable. That variable will be modified
1fbab466 313 * in-place depending on the protocol packet. Must not be NULL.
5faebab2 314 * @param analog Pointer to a struct sr_datafeed_analog_old. The struct will be
ac913e5c 315 * filled with data according to the protocol packet.
1fbab466
UH
316 * Must not be NULL.
317 * @param info Pointer to a struct metex14_info. The struct will be filled
318 * with data according to the protocol packet. Must not be NULL.
ac913e5c
UH
319 *
320 * @return SR_OK upon success, SR_ERR upon failure. Upon errors, the
321 * 'analog' variable contents are undefined and should not be used.
322 */
323SR_PRIV int sr_metex14_parse(const uint8_t *buf, float *floatval,
5faebab2 324 struct sr_datafeed_analog_old *analog, void *info)
ac913e5c
UH
325{
326 int ret;
1fbab466
UH
327 struct metex14_info *info_local;
328
329 info_local = (struct metex14_info *)info;
ac913e5c 330
e82d7dbc
AG
331 /* Don't print byte 13. That one contains the carriage return. */
332 sr_dbg("DMM packet: \"%.13s\"", buf);
333
e83437ae
MH
334 memset(info_local, 0x00, sizeof(struct metex14_info));
335
336 if ((ret = parse_value(buf, info_local, floatval)) != SR_OK) {
ec5186f9 337 sr_dbg("Error parsing value: %d.", ret);
ac913e5c
UH
338 return ret;
339 }
340
1fbab466
UH
341 parse_flags((const char *)buf, info_local);
342 handle_flags(analog, floatval, info_local);
ac913e5c
UH
343
344 return SR_OK;
345}