2 * This file is part of the sigrok project.
4 * Copyright (C) 2012 Bert Vermeulen <bert@biot.com>
5 * Copyright (C) 2012 Alexandru Gagniuc <mr.nuke.me@gmail.com>
7 * This program is free software: you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation, either version 3 of the License, or
10 * (at your option) any later version.
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with this program. If not, see <http://www.gnu.org/licenses/>.
26 #include "libsigrok.h"
27 #include "libsigrok-internal.h"
30 /* Byte 1 of the packet, and the modes it represents */
33 #define IND1_KILO 0x20
34 #define IND1_MEGA 0x10
35 #define IND1_FARAD 0x08
37 #define IND1_VOLT 0x02
38 #define IND1_MILI 0x01
39 /* Byte 2 of the packet, and the modes it represents */
40 #define IND2_MICRO 0x80
41 #define IND2_NANO 0x40
44 #define IND2_DUTY 0x08
48 /* Byte 7 of the packet, and the modes it represents */
49 #define INFO_BEEP 0x80
50 #define INFO_DIODE 0x30
52 #define INFO_HOLD 0x10
55 #define INFO_RS232 0x02
56 #define INFO_AUTO 0x01
57 /* Instead of a decimal point, digit 4 carries the MAX flag */
59 /* Mask to remove the decimal point from a digit */
62 /* What the LCD values represent */
102 MODE_VOLT_WIDTH = 17,
119 static gboolean checksum_valid(const struct rs_22_812_packet *rs_packet)
125 raw = (void *)rs_packet;
127 for (i = 0; i < RS_22_812_PACKET_SIZE - 1; i++)
130 /* This is just a funky constant added to the checksum. */
132 sum -= rs_packet->checksum;
136 static gboolean selection_good(const struct rs_22_812_packet *rs_packet)
140 /* Does the packet have more than one multiplier ? */
142 count += (rs_packet->indicatrix1 & IND1_KILO) ? 1 : 0;
143 count += (rs_packet->indicatrix1 & IND1_MEGA) ? 1 : 0;
144 count += (rs_packet->indicatrix1 & IND1_MILI) ? 1 : 0;
145 count += (rs_packet->indicatrix2 & IND2_MICRO) ? 1 : 0;
146 count += (rs_packet->indicatrix2 & IND2_NANO) ? 1 : 0;
148 sr_err("More than one multiplier detected in packet.");
152 /* Does the packet "measure" more than one type of value? */
154 count += (rs_packet->indicatrix1 & IND1_HZ) ? 1 : 0;
155 count += (rs_packet->indicatrix1 & IND1_OHM) ? 1 : 0;
156 count += (rs_packet->indicatrix1 & IND1_FARAD) ? 1 : 0;
157 count += (rs_packet->indicatrix1 & IND1_AMP) ? 1 : 0;
158 count += (rs_packet->indicatrix1 & IND1_VOLT) ? 1 : 0;
159 count += (rs_packet->indicatrix2 & IND2_DBM) ? 1 : 0;
160 count += (rs_packet->indicatrix2 & IND2_SEC) ? 1 : 0;
161 count += (rs_packet->indicatrix2 & IND2_DUTY) ? 1 : 0;
162 count += (rs_packet->indicatrix2 & IND2_HFE) ? 1 : 0;
164 sr_err("More than one measurement type detected in packet.");
172 * Since the 22-812 does not identify itself in any way, shape, or form,
173 * we really don't know for sure who is sending the data. We must use every
174 * possible check to filter out bad packets, especially since detection of the
175 * 22-812 depends on how well we can filter the packets.
177 SR_PRIV gboolean rs_22_812_packet_valid(const struct rs_22_812_packet *rs_packet)
179 if (!checksum_valid(rs_packet))
182 if (!(rs_packet->mode < MODE_INVALID))
185 if (!selection_good(rs_packet))
191 static uint8_t decode_digit(uint8_t raw_digit)
193 /* Take out the decimal point, so we can use a simple switch(). */
194 raw_digit &= ~DP_MASK;
219 sr_err("Invalid digit byte: 0x%02x.", raw_digit);
224 static double lcd_to_double(const struct rs_22_812_packet *rs_packet, int type)
226 double rawval, multiplier = 1;
227 uint8_t digit, raw_digit;
228 gboolean dp_reached = FALSE;
231 /* end = 1: Don't parse last digit. end = 0: Parse all digits. */
232 end = (type == READ_TEMP) ? 1 : 0;
234 /* We have 4 digits, and we start from the most significant. */
235 for (i = 3; i >= end; i--) {
236 raw_digit = *(&(rs_packet->digit4) + i);
237 digit = decode_digit(raw_digit);
243 * Digit 1 does not have a decimal point. Instead, the decimal
244 * point is used to indicate MAX, so we must avoid testing it.
246 if ((i < 3) && (raw_digit & DP_MASK))
250 rawval = rawval * 10 + digit;
252 rawval *= multiplier;
253 if (rs_packet->info & INFO_NEG)
256 /* See if we need to multiply our raw value by anything. */
257 if (rs_packet->indicatrix1 & IND2_NANO) {
259 } else if (rs_packet->indicatrix2 & IND2_MICRO) {
261 } else if (rs_packet->indicatrix1 & IND1_MILI) {
263 } else if (rs_packet->indicatrix1 & IND1_KILO) {
265 } else if (rs_packet->indicatrix1 & IND1_MEGA) {
272 static gboolean is_celsius(struct rs_22_812_packet *rs_packet)
274 return ((rs_packet->digit4 & ~DP_MASK) == LCD_C);
277 static gboolean is_shortcirc(struct rs_22_812_packet *rs_packet)
279 return ((rs_packet->digit2 & ~DP_MASK) == LCD_h);
282 static gboolean is_logic_high(struct rs_22_812_packet *rs_packet)
284 sr_spew("Digit 2: 0x%02x.", rs_packet->digit2 & ~DP_MASK);
285 return ((rs_packet->digit2 & ~DP_MASK) == LCD_H);
288 static void handle_packet(struct rs_22_812_packet *rs_packet,
289 struct dev_context *devc)
292 struct sr_datafeed_packet packet;
293 struct sr_datafeed_analog *analog;
295 rawval = lcd_to_double(rs_packet, READ_ALL);
297 /* TODO: Check malloc return value. */
298 analog = g_try_malloc0(sizeof(struct sr_datafeed_analog));
299 analog->num_samples = 1;
300 /* TODO: Check malloc return value. */
301 analog->data = g_try_malloc(sizeof(float));
302 *analog->data = (float)rawval;
305 switch (rs_packet->mode) {
307 analog->mq = SR_MQ_VOLTAGE;
308 analog->unit = SR_UNIT_VOLT;
309 analog->mqflags |= SR_MQFLAG_DC;
312 analog->mq = SR_MQ_VOLTAGE;
313 analog->unit = SR_UNIT_VOLT;
314 analog->mqflags |= SR_MQFLAG_AC;
319 analog->mq = SR_MQ_CURRENT;
320 analog->unit = SR_UNIT_AMPERE;
321 analog->mqflags |= SR_MQFLAG_DC;
326 analog->mq = SR_MQ_CURRENT;
327 analog->unit = SR_UNIT_AMPERE;
328 analog->mqflags |= SR_MQFLAG_AC;
331 analog->mq = SR_MQ_RESISTANCE;
332 analog->unit = SR_UNIT_OHM;
335 analog->mq = SR_MQ_CAPACITANCE;
336 analog->unit = SR_UNIT_FARAD;
339 analog->mq = SR_MQ_CONTINUITY;
340 analog->unit = SR_UNIT_BOOLEAN;
341 *analog->data = is_shortcirc(rs_packet);
344 analog->mq = SR_MQ_VOLTAGE;
345 analog->unit = SR_UNIT_VOLT;
346 analog->mqflags |= SR_MQFLAG_DIODE | SR_MQFLAG_DC;
351 analog->mq = SR_MQ_FREQUENCY;
352 analog->unit = SR_UNIT_HERTZ;
356 * No matter whether or not we have an actual voltage reading,
357 * we are measuring voltage, so we set our MQ as VOLTAGE.
359 analog->mq = SR_MQ_VOLTAGE;
360 if (!isnan(rawval)) {
361 /* We have an actual voltage. */
362 analog->unit = SR_UNIT_VOLT;
364 /* We have either HI or LOW. */
365 analog->unit = SR_UNIT_BOOLEAN;
366 *analog->data = is_logic_high(rs_packet);
370 analog->mq = SR_MQ_GAIN;
371 analog->unit = SR_UNIT_UNITLESS;
376 analog->mq = SR_MQ_DUTY_CYCLE;
377 analog->unit = SR_UNIT_PERCENTAGE;
380 case MODE_VOLT_WIDTH:
382 analog->mq = SR_MQ_PULSE_WIDTH;
383 analog->unit = SR_UNIT_SECOND;
385 analog->mq = SR_MQ_TEMPERATURE;
386 /* We need to reparse. */
387 *analog->data = lcd_to_double(rs_packet, READ_TEMP);
388 analog->unit = is_celsius(rs_packet) ?
389 SR_UNIT_CELSIUS : SR_UNIT_FAHRENHEIT;
392 analog->mq = SR_MQ_POWER;
393 analog->unit = SR_UNIT_DECIBEL_MW;
394 analog->mqflags |= SR_MQFLAG_AC;
397 sr_err("Unknown mode: %d.", rs_packet->mode);
401 if (rs_packet->info & INFO_HOLD)
402 analog->mqflags |= SR_MQFLAG_HOLD;
403 if (rs_packet->digit4 & DIG4_MAX)
404 analog->mqflags |= SR_MQFLAG_MAX;
405 if (rs_packet->indicatrix2 & IND2_MIN)
406 analog->mqflags |= SR_MQFLAG_MIN;
407 if (rs_packet->info & INFO_AUTO)
408 analog->mqflags |= SR_MQFLAG_AUTORANGE;
410 if (analog->mq != -1) {
411 /* Got a measurement. */
412 sr_spew("Value: %f.", rawval);
413 packet.type = SR_DF_ANALOG;
414 packet.payload = analog;
415 sr_session_send(devc->cb_data, &packet);
418 g_free(analog->data);
422 static void handle_new_data(struct dev_context *devc, int fd)
425 size_t i, offset = 0;
426 struct rs_22_812_packet *rs_packet;
428 /* Try to get as much data as the buffer can hold. */
429 len = RS_DMM_BUFSIZE - devc->buflen;
430 len = serial_read(fd, devc->buf + devc->buflen, len);
432 sr_err("Serial port read error.");
437 /* Now look for packets in that data. */
438 while ((devc->buflen - offset) >= RS_22_812_PACKET_SIZE) {
439 rs_packet = (void *)(devc->buf + offset);
440 if (rs_22_812_packet_valid(rs_packet)) {
441 handle_packet(rs_packet, devc);
442 offset += RS_22_812_PACKET_SIZE;
448 /* If we have any data left, move it to the beginning of our buffer. */
449 for (i = 0; i < devc->buflen - offset; i++)
450 devc->buf[i] = devc->buf[offset + i];
451 devc->buflen -= offset;
454 SR_PRIV int radioshack_dmm_receive_data(int fd, int revents, void *cb_data)
456 struct sr_dev_inst *sdi;
457 struct dev_context *devc;
459 if (!(sdi = cb_data))
462 if (!(devc = sdi->priv))
465 if (revents == G_IO_IN) {
466 /* Serial data arrived. */
467 handle_new_data(devc, fd);
470 if (devc->num_samples >= devc->limit_samples) {
471 sdi->driver->dev_acquisition_stop(sdi, cb_data);