[libsigrok.git] / hardware / radioshack-dmm / protocol.c

/*
 * This file is part of the sigrok project.
 *
 * Copyright (C) 2012 Bert Vermeulen <bert@biot.com>
 * Copyright (C) 2012 Alexandru Gagniuc <mr.nuke.me@gmail.com>
 *
 * This program 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 3 of the License, or
 * (at your option) any later version.
 *
 * This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <stdlib.h>
#include <math.h>
#include <string.h>
#include <errno.h>
#include <glib.h>
#include "libsigrok.h"
#include "libsigrok-internal.h"
#include "protocol.h"

/* Byte 1 of the packet, and the modes it represents */
#define IND1_HZ		0x80
#define IND1_OHM	0x40
#define IND1_KILO	0x20
#define IND1_MEGA	0x10
#define IND1_FARAD	0x08
#define IND1_AMP	0x04
#define IND1_VOLT	0x02
#define IND1_MILI	0x01
/* Byte 2 of the packet, and the modes it represents */
#define IND2_MICRO	0x80
#define IND2_NANO	0x40
#define IND2_DBM	0x20
#define IND2_SEC	0x10
#define IND2_DUTY	0x08
#define IND2_HFE	0x04
#define IND2_REL	0x02
#define IND2_MIN	0x01
/* Byte 7 of the packet, and the modes it represents */
#define INFO_BEEP	0x80
#define INFO_DIODE	0x30
#define INFO_BAT	0x20
#define INFO_HOLD	0x10
#define INFO_NEG	0x08
#define INFO_AC		0x04
#define INFO_RS232	0x02
#define INFO_AUTO	0x01
/* Instead of a decimal point, digit 4 carries the MAX flag */
#define DIG4_MAX	0x08
/* Mask to remove the decimal point from a digit */
#define DP_MASK		0x08

/* What the LCD values represent */
#define LCD_0		0xd7
#define LCD_1		0x50
#define LCD_2		0xb5
#define LCD_3		0xf1
#define LCD_4		0x72
#define LCD_5		0xe3
#define LCD_6		0xe7
#define LCD_7		0x51
#define LCD_8		0xf7
#define LCD_9		0xf3

#define LCD_C		0x87
#define LCD_E
#define LCD_F
#define LCD_h		0x66
#define LCD_H		0x76
#define LCD_I
#define LCD_n
#define LCD_P		0x37
#define LCD_r

enum {
	MODE_DC_V	= 0,
	MODE_AC_V	= 1,
	MODE_DC_UA	= 2,
	MODE_DC_MA	= 3,
	MODE_DC_A 	= 4,
	MODE_AC_UA	= 5,
	MODE_AC_MA	= 6,
	MODE_AC_A	= 7,
	MODE_OHM	= 8,
	MODE_FARAD	= 9,
	MODE_HZ		= 10,
	MODE_VOLT_HZ	= 11,
	MODE_AMP_HZ	= 12,
	MODE_DUTY	= 13,
	MODE_VOLT_DUTY	= 14,
	MODE_AMP_DUTY	= 15,
	MODE_WIDTH	= 16,
	MODE_VOLT_WIDTH	= 17,
	MODE_AMP_WIDTH	= 18,
	MODE_DIODE	= 19,
	MODE_CONT	= 20,
	MODE_HFE	= 21,
	MODE_LOGIC	= 22,
	MODE_DBM	= 23,
	// MODE_EF	= 24,
	MODE_TEMP	= 25,
	MODE_INVALID	= 26,
};

enum {
	READ_ALL,
	READ_TEMP,
};

static gboolean checksum_valid(const struct rs_22_812_packet *rs_packet)
{
	uint8_t *raw;
	uint8_t sum = 0;
	int i;

	raw = (void *)rs_packet;

	for (i = 0; i < RS_22_812_PACKET_SIZE - 1; i++)
		sum += raw[i];

	/* This is just a funky constant added to the checksum. */
	sum += 57;
	sum -= rs_packet->checksum;
	return (sum == 0);
}

static gboolean selection_good(const struct rs_22_812_packet *rs_packet)
{
	int count;

	/* Does the packet have more than one multiplier ? */
	count = 0;
	count += (rs_packet->indicatrix1 & IND1_KILO)  ? 1 : 0;
	count += (rs_packet->indicatrix1 & IND1_MEGA)  ? 1 : 0;
	count += (rs_packet->indicatrix1 & IND1_MILI)  ? 1 : 0;
	count += (rs_packet->indicatrix2 & IND2_MICRO) ? 1 : 0;
	count += (rs_packet->indicatrix2 & IND2_NANO)  ? 1 : 0;
	if (count > 1) {
		sr_err("More than one multiplier detected in packet.");
		return FALSE;
	}

	/* Does the packet "measure" more than one type of value? */
	count = 0;
	count += (rs_packet->indicatrix1 & IND1_HZ)    ? 1 : 0;
	count += (rs_packet->indicatrix1 & IND1_OHM)   ? 1 : 0;
	count += (rs_packet->indicatrix1 & IND1_FARAD) ? 1 : 0;
	count += (rs_packet->indicatrix1 & IND1_AMP)   ? 1 : 0;
	count += (rs_packet->indicatrix1 & IND1_VOLT)  ? 1 : 0;
	count += (rs_packet->indicatrix2 & IND2_DBM)   ? 1 : 0;
	count += (rs_packet->indicatrix2 & IND2_SEC)   ? 1 : 0;
	count += (rs_packet->indicatrix2 & IND2_DUTY)  ? 1 : 0;
	count += (rs_packet->indicatrix2 & IND2_HFE)   ? 1 : 0;
	if (count > 1) {
		sr_err("More than one measurement type detected in packet.");
		return FALSE;
	}

	return TRUE;
}

/*
 * Since the 22-812 does not identify itself in any way, shape, or form,
 * we really don't know for sure who is sending the data. We must use every
 * possible check to filter out bad packets, especially since detection of the
 * 22-812 depends on how well we can filter the packets.
 */
SR_PRIV gboolean rs_22_812_packet_valid(const struct rs_22_812_packet *rs_packet)
{
	if (!checksum_valid(rs_packet))
		return FALSE;

	if (!(rs_packet->mode < MODE_INVALID))
		return FALSE;

	if (!selection_good(rs_packet))
		return FALSE;

	return TRUE;
}

static uint8_t decode_digit(uint8_t raw_digit)
{
	/* Take out the decimal point, so we can use a simple switch(). */
	raw_digit &= ~DP_MASK;

	switch (raw_digit) {
	case 0x00:
	case LCD_0:
		return 0;
	case LCD_1:
		return 1;
	case LCD_2:
		return 2;
	case LCD_3:
		return 3;
	case LCD_4:
		return 4;
	case LCD_5:
		return 5;
	case LCD_6:
		return 6;
	case LCD_7:
		return 7;
	case LCD_8:
		return 8;
	case LCD_9:
		return 9;
	default:
		sr_err("Invalid digit byte: 0x%02x.", raw_digit);
		return 0xff;
	}
}

static double lcd_to_double(const struct rs_22_812_packet *rs_packet, int type)
{
	double rawval, multiplier = 1;
	uint8_t digit, raw_digit;
	gboolean dp_reached = FALSE;
	int i, end;

	/* end = 1: Don't parse last digit. end = 0: Parse all digits. */
	end = (type == READ_TEMP) ? 1 : 0;

	/* We have 4 digits, and we start from the most significant. */
	for (i = 3; i >= end; i--) {
		raw_digit = *(&(rs_packet->digit4) + i);
		digit = decode_digit(raw_digit);
		if (digit == 0xff) {
			rawval = NAN;
			break;
		}
		/*
		 * Digit 1 does not have a decimal point. Instead, the decimal
		 * point is used to indicate MAX, so we must avoid testing it.
		 */
		if ((i < 3) && (raw_digit & DP_MASK))
			dp_reached = TRUE;
		if (dp_reached)
			multiplier /= 10;
		rawval = rawval * 10 + digit;
	}
	rawval *= multiplier;
	if (rs_packet->info & INFO_NEG)
		rawval *= -1;

	/* See if we need to multiply our raw value by anything. */
	if (rs_packet->indicatrix1 & IND2_NANO) {
		rawval *= 1E-9;
	} else if (rs_packet->indicatrix2 & IND2_MICRO) {
		rawval *= 1E-6;
	} else if (rs_packet->indicatrix1 & IND1_MILI) {
		rawval *= 1E-3;
	} else if (rs_packet->indicatrix1 & IND1_KILO) {
		rawval *= 1E3;
	} else if (rs_packet->indicatrix1 & IND1_MEGA) {
		rawval *= 1E6;
	}

	return rawval;
}

static gboolean is_celsius(struct rs_22_812_packet *rs_packet)
{
	return ((rs_packet->digit4 & ~DP_MASK) == LCD_C);
}

static gboolean is_shortcirc(struct rs_22_812_packet *rs_packet)
{
	return ((rs_packet->digit2 & ~DP_MASK) == LCD_h);
}

static gboolean is_logic_high(struct rs_22_812_packet *rs_packet)
{
	sr_spew("Digit 2: 0x%02x.", rs_packet->digit2 & ~DP_MASK);
	return ((rs_packet->digit2 & ~DP_MASK) == LCD_H);
}

static void handle_packet(struct rs_22_812_packet *rs_packet,
			  struct dev_context *devc)
{
	double rawval;
	struct sr_datafeed_packet packet;
	struct sr_datafeed_analog *analog;

	rawval = lcd_to_double(rs_packet, READ_ALL);

	/* TODO: Check malloc return value. */
	analog = g_try_malloc0(sizeof(struct sr_datafeed_analog));
	analog->num_samples = 1;
	/* TODO: Check malloc return value. */
	analog->data = g_try_malloc(sizeof(float));
	*analog->data = (float)rawval;
	analog->mq = -1;

	switch (rs_packet->mode) {
	case MODE_DC_V:
		analog->mq = SR_MQ_VOLTAGE;
		analog->unit = SR_UNIT_VOLT;
		analog->mqflags |= SR_MQFLAG_DC;
		break;
	case MODE_AC_V:
		analog->mq = SR_MQ_VOLTAGE;
		analog->unit = SR_UNIT_VOLT;
		analog->mqflags |= SR_MQFLAG_AC;
		break;
	case MODE_DC_UA:
	case MODE_DC_MA:
	case MODE_DC_A:
		analog->mq = SR_MQ_CURRENT;
		analog->unit = SR_UNIT_AMPERE;
		analog->mqflags |= SR_MQFLAG_DC;
		break;
	case MODE_AC_UA:
	case MODE_AC_MA:
	case MODE_AC_A:
		analog->mq = SR_MQ_CURRENT;
		analog->unit = SR_UNIT_AMPERE;
		analog->mqflags |= SR_MQFLAG_AC;
		break;
	case MODE_OHM:
		analog->mq = SR_MQ_RESISTANCE;
		analog->unit = SR_UNIT_OHM;
		break;
	case MODE_FARAD:
		analog->mq = SR_MQ_CAPACITANCE;
		analog->unit = SR_UNIT_FARAD;
		break;
	case MODE_CONT:
		analog->mq = SR_MQ_CONTINUITY;
		analog->unit = SR_UNIT_BOOLEAN;
		*analog->data = is_shortcirc(rs_packet);
		break;
	case MODE_DIODE:
		analog->mq = SR_MQ_VOLTAGE;
		analog->unit = SR_UNIT_VOLT;
		analog->mqflags |= SR_MQFLAG_DIODE | SR_MQFLAG_DC;
		break;
	case MODE_HZ:
	case MODE_VOLT_HZ:
	case MODE_AMP_HZ:
		analog->mq = SR_MQ_FREQUENCY;
		analog->unit = SR_UNIT_HERTZ;
		break;
	case MODE_LOGIC:
		/*
		 * No matter whether or not we have an actual voltage reading,
		 * we are measuring voltage, so we set our MQ as VOLTAGE.
		 */
		analog->mq = SR_MQ_VOLTAGE;
		if (!isnan(rawval)) {
			/* We have an actual voltage. */
			analog->unit = SR_UNIT_VOLT;
		} else {
			/* We have either HI or LOW. */
			analog->unit = SR_UNIT_BOOLEAN;
			*analog->data = is_logic_high(rs_packet);
		}
		break;
	case MODE_HFE:
		analog->mq = SR_MQ_GAIN;
		analog->unit = SR_UNIT_UNITLESS;
		break;
	case MODE_DUTY:
	case MODE_VOLT_DUTY:
	case MODE_AMP_DUTY:
		analog->mq = SR_MQ_DUTY_CYCLE;
		analog->unit = SR_UNIT_PERCENTAGE;
		break;
	case MODE_WIDTH:
	case MODE_VOLT_WIDTH:
	case MODE_AMP_WIDTH:
		analog->mq = SR_MQ_PULSE_WIDTH;
		analog->unit = SR_UNIT_SECOND;
	case MODE_TEMP:
		analog->mq = SR_MQ_TEMPERATURE;
		/* We need to reparse. */
		*analog->data = lcd_to_double(rs_packet, READ_TEMP);
		analog->unit = is_celsius(rs_packet) ?
		               SR_UNIT_CELSIUS : SR_UNIT_FAHRENHEIT;
		break;
	case MODE_DBM:
		analog->mq = SR_MQ_POWER;
		analog->unit = SR_UNIT_DECIBEL_MW;
		analog->mqflags |= SR_MQFLAG_AC;
		break;
	default:
		sr_err("Unknown mode: %d.", rs_packet->mode);
		break;
	}

	if (rs_packet->info & INFO_HOLD)
		analog->mqflags |= SR_MQFLAG_HOLD;
	if (rs_packet->digit4 & DIG4_MAX)
		analog->mqflags |= SR_MQFLAG_MAX;
	if (rs_packet->indicatrix2 & IND2_MIN)
		analog->mqflags |= SR_MQFLAG_MIN;
	if (rs_packet->info & INFO_AUTO)
		analog->mqflags |= SR_MQFLAG_AUTORANGE;

	if (analog->mq != -1) {
		/* Got a measurement. */
		sr_spew("Value: %f.", rawval);
		packet.type = SR_DF_ANALOG;
		packet.payload = analog;
		sr_session_send(devc->cb_data, &packet);
		devc->num_samples++;
	}
	g_free(analog->data);
	g_free(analog);
}

static void handle_new_data(struct dev_context *devc, int fd)
{
	int len;
	size_t i, offset = 0;
	struct rs_22_812_packet *rs_packet;

	/* Try to get as much data as the buffer can hold. */
	len = RS_DMM_BUFSIZE - devc->buflen;
	len = serial_read(fd, devc->buf + devc->buflen, len);
	if (len < 1) {
		sr_err("Serial port read error.");
		return;
	}
	devc->buflen += len;

	/* Now look for packets in that data. */
	while ((devc->buflen - offset) >= RS_22_812_PACKET_SIZE) {
		rs_packet = (void *)(devc->buf + offset);
		if (rs_22_812_packet_valid(rs_packet)) {
			handle_packet(rs_packet, devc);
			offset += RS_22_812_PACKET_SIZE;
		} else {
			offset++;
		}
	}

	/* If we have any data left, move it to the beginning of our buffer. */
	for (i = 0; i < devc->buflen - offset; i++)
		devc->buf[i] = devc->buf[offset + i];
	devc->buflen -= offset;
}

SR_PRIV int radioshack_dmm_receive_data(int fd, int revents, void *cb_data)
{
	struct sr_dev_inst *sdi;
	struct dev_context *devc;

	if (!(sdi = cb_data))
		return TRUE;

	if (!(devc = sdi->priv))
		return TRUE;

	if (revents == G_IO_IN) {
		/* Serial data arrived. */
		handle_new_data(devc, fd);
	}

	if (devc->num_samples >= devc->limit_samples) {
		sdi->driver->dev_acquisition_stop(sdi, cb_data);
		return TRUE;
	}

	return TRUE;
}
Commit	Line	Data
d375b3c3 AG	1	/*
	2	* This file is part of the sigrok project.
	3	*
	4	* Copyright (C) 2012 Bert Vermeulen <bert@biot.com>
	5	* Copyright (C) 2012 Alexandru Gagniuc <mr.nuke.me@gmail.com>
	6	*
	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.
	11	*
	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.
	16	*
	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/>.
	19	*/
	20
d375b3c3 AG	21	#include <stdlib.h>
	22	#include <math.h>
	23	#include <string.h>
	24	#include <errno.h>
ba6383f8 UH	25	#include <glib.h>
	26	#include "libsigrok.h"
	27	#include "libsigrok-internal.h"
936e27f1	28	#include "protocol.h"
ba6383f8	29
4e172b8f UH	30	/* Byte 1 of the packet, and the modes it represents */
	31	#define IND1_HZ 0x80
	32	#define IND1_OHM 0x40
	33	#define IND1_KILO 0x20
	34	#define IND1_MEGA 0x10
	35	#define IND1_FARAD 0x08
	36	#define IND1_AMP 0x04
	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
	42	#define IND2_DBM 0x20
	43	#define IND2_SEC 0x10
	44	#define IND2_DUTY 0x08
	45	#define IND2_HFE 0x04
	46	#define IND2_REL 0x02
	47	#define IND2_MIN 0x01
	48	/* Byte 7 of the packet, and the modes it represents */
	49	#define INFO_BEEP 0x80
	50	#define INFO_DIODE 0x30
	51	#define INFO_BAT 0x20
	52	#define INFO_HOLD 0x10
	53	#define INFO_NEG 0x08
	54	#define INFO_AC 0x04
	55	#define INFO_RS232 0x02
	56	#define INFO_AUTO 0x01
	57	/* Instead of a decimal point, digit 4 carries the MAX flag */
	58	#define DIG4_MAX 0x08
	59	/* Mask to remove the decimal point from a digit */
	60	#define DP_MASK 0x08
	61
	62	/* What the LCD values represent */
	63	#define LCD_0 0xd7
	64	#define LCD_1 0x50
	65	#define LCD_2 0xb5
	66	#define LCD_3 0xf1
	67	#define LCD_4 0x72
	68	#define LCD_5 0xe3
	69	#define LCD_6 0xe7
	70	#define LCD_7 0x51
	71	#define LCD_8 0xf7
	72	#define LCD_9 0xf3
	73
	74	#define LCD_C 0x87
	75	#define LCD_E
	76	#define LCD_F
	77	#define LCD_h 0x66
	78	#define LCD_H 0x76
	79	#define LCD_I
	80	#define LCD_n
	81	#define LCD_P 0x37
	82	#define LCD_r
	83
	84	enum {
	85	MODE_DC_V = 0,
	86	MODE_AC_V = 1,
	87	MODE_DC_UA = 2,
	88	MODE_DC_MA = 3,
	89	MODE_DC_A = 4,
	90	MODE_AC_UA = 5,
	91	MODE_AC_MA = 6,
	92	MODE_AC_A = 7,
	93	MODE_OHM = 8,
94	MODE_FARAD = 9,
95	MODE_HZ = 10,
96	MODE_VOLT_HZ = 11,
97	MODE_AMP_HZ = 12,
98	MODE_DUTY = 13,
99	MODE_VOLT_DUTY = 14,
100	MODE_AMP_DUTY = 15,
101	MODE_WIDTH = 16,
102	MODE_VOLT_WIDTH = 17,
103	MODE_AMP_WIDTH = 18,
104	MODE_DIODE = 19,
105	MODE_CONT = 20,
106	MODE_HFE = 21,
107	MODE_LOGIC = 22,
108	MODE_DBM = 23,
109	// MODE_EF = 24,
110	MODE_TEMP = 25,
111	MODE_INVALID = 26,
112	};
113
ba6383f8 UH	114	enum {
	115	READ_ALL,
	116	READ_TEMP,
	117	};
d375b3c3	118
ba6383f8	119	static gboolean checksum_valid(const struct rs_22_812_packet *rs_packet)
d375b3c3	120	{
ba6383f8	121	uint8_t *raw;
d375b3c3	122	uint8_t sum = 0;
ba6383f8 UH	123	int i;
	124
	125	raw = (void *)rs_packet;
	126
	127	for (i = 0; i < RS_22_812_PACKET_SIZE - 1; i++)
d375b3c3	128	sum += raw[i];
ba6383f8 UH	129
ba6383f8 UH	130	/* This is just a funky constant added to the checksum. */
d375b3c3	131	sum += 57;
ba6383f8 UH	132	sum -= rs_packet->checksum;
ba6383f8 UH	133	return (sum == 0);
d375b3c3 AG	134	}
d375b3c3 AG	135
ba6383f8	136	static gboolean selection_good(const struct rs_22_812_packet *rs_packet)
d375b3c3	137	{
ba6383f8	138	int count;
d375b3c3	139
d375b3c3	140	/* Does the packet have more than one multiplier ? */
ba6383f8	141	count = 0;
4e172b8f UH	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;
ba6383f8 UH	147	if (count > 1) {
ba6383f8 UH	148	sr_err("More than one multiplier detected in packet.");
d375b3c3	149	return FALSE;
ba6383f8	150	}
d375b3c3	151
ba6383f8 UH	152	/* Does the packet "measure" more than one type of value? */
ba6383f8 UH	153	count = 0;
4e172b8f UH	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;
ba6383f8 UH	163	if (count > 1) {
ba6383f8 UH	164	sr_err("More than one measurement type detected in packet.");
d375b3c3	165	return FALSE;
ba6383f8	166	}
d375b3c3	167
d375b3c3 AG	168	return TRUE;
	169	}
	170
ba6383f8 UH	171	/*
ba6383f8 UH	172	* Since the 22-812 does not identify itself in any way, shape, or form,
d375b3c3 AG	173	* we really don't know for sure who is sending the data. We must use every
d375b3c3 AG	174	* possible check to filter out bad packets, especially since detection of the
ba6383f8 UH	175	* 22-812 depends on how well we can filter the packets.
	176	*/
	177	SR_PRIV gboolean rs_22_812_packet_valid(const struct rs_22_812_packet *rs_packet)
d375b3c3	178	{
ba6383f8	179	if (!checksum_valid(rs_packet))
d375b3c3 AG	180	return FALSE;
d375b3c3 AG	181
4e172b8f	182	if (!(rs_packet->mode < MODE_INVALID))
d375b3c3 AG	183	return FALSE;
d375b3c3 AG	184
ba6383f8	185	if (!selection_good(rs_packet))
d375b3c3	186	return FALSE;
ba6383f8	187
d375b3c3 AG	188	return TRUE;
	189	}
	190
ba6383f8	191	static uint8_t decode_digit(uint8_t raw_digit)
d375b3c3	192	{
ba6383f8	193	/* Take out the decimal point, so we can use a simple switch(). */
4e172b8f	194	raw_digit &= ~DP_MASK;
ba6383f8 UH	195
ba6383f8 UH	196	switch (raw_digit) {
d375b3c3	197	case 0x00:
4e172b8f	198	case LCD_0:
d375b3c3	199	return 0;
4e172b8f	200	case LCD_1:
d375b3c3	201	return 1;
4e172b8f	202	case LCD_2:
d375b3c3	203	return 2;
4e172b8f	204	case LCD_3:
d375b3c3	205	return 3;
4e172b8f	206	case LCD_4:
d375b3c3	207	return 4;
4e172b8f	208	case LCD_5:
d375b3c3	209	return 5;
4e172b8f	210	case LCD_6:
d375b3c3	211	return 6;
4e172b8f	212	case LCD_7:
d375b3c3	213	return 7;
4e172b8f	214	case LCD_8:
d375b3c3	215	return 8;
4e172b8f	216	case LCD_9:
d375b3c3 AG	217	return 9;
d375b3c3 AG	218	default:
ba6383f8	219	sr_err("Invalid digit byte: 0x%02x.", raw_digit);
d375b3c3 AG	220	return 0xff;
	221	}
	222	}
	223
4e172b8f	224	static double lcd_to_double(const struct rs_22_812_packet *rs_packet, int type)
d375b3c3	225	{
ba6383f8 UH	226	double rawval, multiplier = 1;
ba6383f8 UH	227	uint8_t digit, raw_digit;
d375b3c3 AG	228	gboolean dp_reached = FALSE;
d375b3c3 AG	229	int i, end;
ba6383f8 UH	230
	231	/* end = 1: Don't parse last digit. end = 0: Parse all digits. */
	232	end = (type == READ_TEMP) ? 1 : 0;
	233
	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);
	238	if (digit == 0xff) {
d375b3c3 AG	239	rawval = NAN;
	240	break;
	241	}
ba6383f8 UH	242	/*
	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.
	245	*/
4e172b8f	246	if ((i < 3) && (raw_digit & DP_MASK))
d375b3c3	247	dp_reached = TRUE;
ba6383f8 UH	248	if (dp_reached)
ba6383f8 UH	249	multiplier /= 10;
d375b3c3 AG	250	rawval = rawval * 10 + digit;
	251	}
	252	rawval *= multiplier;
4e172b8f	253	if (rs_packet->info & INFO_NEG)
d375b3c3 AG	254	rawval *= -1;
d375b3c3 AG	255
ba6383f8	256	/* See if we need to multiply our raw value by anything. */
4e172b8f	257	if (rs_packet->indicatrix1 & IND2_NANO) {
d375b3c3	258	rawval *= 1E-9;
4e172b8f	259	} else if (rs_packet->indicatrix2 & IND2_MICRO) {
d375b3c3	260	rawval *= 1E-6;
4e172b8f	261	} else if (rs_packet->indicatrix1 & IND1_MILI) {
d375b3c3	262	rawval *= 1E-3;
4e172b8f	263	} else if (rs_packet->indicatrix1 & IND1_KILO) {
d375b3c3	264	rawval *= 1E3;
4e172b8f	265	} else if (rs_packet->indicatrix1 & IND1_MEGA) {
d375b3c3 AG	266	rawval *= 1E6;
	267	}
	268
	269	return rawval;
	270	}
	271
ba6383f8	272	static gboolean is_celsius(struct rs_22_812_packet *rs_packet)
d375b3c3	273	{
4e172b8f	274	return ((rs_packet->digit4 & ~DP_MASK) == LCD_C);
d375b3c3 AG	275	}
d375b3c3 AG	276
ba6383f8	277	static gboolean is_shortcirc(struct rs_22_812_packet *rs_packet)
d375b3c3	278	{
4e172b8f	279	return ((rs_packet->digit2 & ~DP_MASK) == LCD_h);
d375b3c3 AG	280	}
d375b3c3 AG	281
ba6383f8	282	static gboolean is_logic_high(struct rs_22_812_packet *rs_packet)
7c41dc47	283	{
4e172b8f UH	284	sr_spew("Digit 2: 0x%02x.", rs_packet->digit2 & ~DP_MASK);
4e172b8f UH	285	return ((rs_packet->digit2 & ~DP_MASK) == LCD_H);
7c41dc47 AG	286	}
7c41dc47 AG	287
ba6383f8 UH	288	static void handle_packet(struct rs_22_812_packet *rs_packet,
ba6383f8 UH	289	struct dev_context *devc)
d375b3c3	290	{
ba6383f8	291	double rawval;
d375b3c3 AG	292	struct sr_datafeed_packet packet;
	293	struct sr_datafeed_analog *analog;
	294
4e172b8f	295	rawval = lcd_to_double(rs_packet, READ_ALL);
ba6383f8	296
886a52b6	297	/* TODO: Check malloc return value. */
d375b3c3 AG	298	analog = g_try_malloc0(sizeof(struct sr_datafeed_analog));
d375b3c3 AG	299	analog->num_samples = 1;
886a52b6	300	/* TODO: Check malloc return value. */
d375b3c3 AG	301	analog->data = g_try_malloc(sizeof(float));
	302	*analog->data = (float)rawval;
	303	analog->mq = -1;
	304
ba6383f8	305	switch (rs_packet->mode) {
4e172b8f	306	case MODE_DC_V:
d375b3c3 AG	307	analog->mq = SR_MQ_VOLTAGE;
	308	analog->unit = SR_UNIT_VOLT;
	309	analog->mqflags \|= SR_MQFLAG_DC;
	310	break;
4e172b8f	311	case MODE_AC_V:
d375b3c3 AG	312	analog->mq = SR_MQ_VOLTAGE;
	313	analog->unit = SR_UNIT_VOLT;
	314	analog->mqflags \|= SR_MQFLAG_AC;
	315	break;
4e172b8f UH	316	case MODE_DC_UA:
	317	case MODE_DC_MA:
	318	case MODE_DC_A:
d375b3c3 AG	319	analog->mq = SR_MQ_CURRENT;
	320	analog->unit = SR_UNIT_AMPERE;
	321	analog->mqflags \|= SR_MQFLAG_DC;
	322	break;
4e172b8f UH	323	case MODE_AC_UA:
	324	case MODE_AC_MA:
	325	case MODE_AC_A:
d375b3c3 AG	326	analog->mq = SR_MQ_CURRENT;
	327	analog->unit = SR_UNIT_AMPERE;
	328	analog->mqflags \|= SR_MQFLAG_AC;
	329	break;
4e172b8f	330	case MODE_OHM:
d375b3c3 AG	331	analog->mq = SR_MQ_RESISTANCE;
	332	analog->unit = SR_UNIT_OHM;
	333	break;
4e172b8f	334	case MODE_FARAD:
d375b3c3 AG	335	analog->mq = SR_MQ_CAPACITANCE;
	336	analog->unit = SR_UNIT_FARAD;
	337	break;
4e172b8f	338	case MODE_CONT:
d375b3c3 AG	339	analog->mq = SR_MQ_CONTINUITY;
d375b3c3 AG	340	analog->unit = SR_UNIT_BOOLEAN;
ba6383f8	341	*analog->data = is_shortcirc(rs_packet);
d375b3c3	342	break;
4e172b8f	343	case MODE_DIODE:
d375b3c3 AG	344	analog->mq = SR_MQ_VOLTAGE;
	345	analog->unit = SR_UNIT_VOLT;
	346	analog->mqflags \|= SR_MQFLAG_DIODE \| SR_MQFLAG_DC;
	347	break;
4e172b8f UH	348	case MODE_HZ:
	349	case MODE_VOLT_HZ:
	350	case MODE_AMP_HZ:
d375b3c3 AG	351	analog->mq = SR_MQ_FREQUENCY;
	352	analog->unit = SR_UNIT_HERTZ;
	353	break;
4e172b8f	354	case MODE_LOGIC:
ba6383f8 UH	355	/*
	356	* No matter whether or not we have an actual voltage reading,
	357	* we are measuring voltage, so we set our MQ as VOLTAGE.
	358	*/
7c41dc47	359	analog->mq = SR_MQ_VOLTAGE;
ba6383f8 UH	360	if (!isnan(rawval)) {
ba6383f8 UH	361	/* We have an actual voltage. */
7c41dc47 AG	362	analog->unit = SR_UNIT_VOLT;
7c41dc47 AG	363	} else {
ba6383f8	364	/* We have either HI or LOW. */
7c41dc47	365	analog->unit = SR_UNIT_BOOLEAN;
ba6383f8	366	*analog->data = is_logic_high(rs_packet);
7c41dc47	367	}
d375b3c3	368	break;
4e172b8f	369	case MODE_HFE:
d375b3c3 AG	370	analog->mq = SR_MQ_GAIN;
	371	analog->unit = SR_UNIT_UNITLESS;
	372	break;
4e172b8f UH	373	case MODE_DUTY:
	374	case MODE_VOLT_DUTY:
	375	case MODE_AMP_DUTY:
d375b3c3 AG	376	analog->mq = SR_MQ_DUTY_CYCLE;
	377	analog->unit = SR_UNIT_PERCENTAGE;
	378	break;
4e172b8f UH	379	case MODE_WIDTH:
	380	case MODE_VOLT_WIDTH:
	381	case MODE_AMP_WIDTH:
d375b3c3 AG	382	analog->mq = SR_MQ_PULSE_WIDTH;
d375b3c3 AG	383	analog->unit = SR_UNIT_SECOND;
4e172b8f	384	case MODE_TEMP:
d375b3c3	385	analog->mq = SR_MQ_TEMPERATURE;
ba6383f8	386	/* We need to reparse. */
4e172b8f	387	*analog->data = lcd_to_double(rs_packet, READ_TEMP);
ba6383f8 UH	388	analog->unit = is_celsius(rs_packet) ?
ba6383f8 UH	389	SR_UNIT_CELSIUS : SR_UNIT_FAHRENHEIT;
d375b3c3	390	break;
4e172b8f	391	case MODE_DBM:
d375b3c3 AG	392	analog->mq = SR_MQ_POWER;
	393	analog->unit = SR_UNIT_DECIBEL_MW;
	394	analog->mqflags \|= SR_MQFLAG_AC;
	395	break;
	396	default:
ba6383f8	397	sr_err("Unknown mode: %d.", rs_packet->mode);
d375b3c3 AG	398	break;
	399	}
	400
4e172b8f	401	if (rs_packet->info & INFO_HOLD)
d375b3c3	402	analog->mqflags \|= SR_MQFLAG_HOLD;
4e172b8f	403	if (rs_packet->digit4 & DIG4_MAX)
d375b3c3	404	analog->mqflags \|= SR_MQFLAG_MAX;
4e172b8f	405	if (rs_packet->indicatrix2 & IND2_MIN)
d375b3c3	406	analog->mqflags \|= SR_MQFLAG_MIN;
4e172b8f	407	if (rs_packet->info & INFO_AUTO)
d375b3c3	408	analog->mqflags \|= SR_MQFLAG_AUTORANGE;
d375b3c3 AG	409
	410	if (analog->mq != -1) {
	411	/* Got a measurement. */
dccbd0ed	412	sr_spew("Value: %f.", rawval);
d375b3c3 AG	413	packet.type = SR_DF_ANALOG;
	414	packet.payload = analog;
	415	sr_session_send(devc->cb_data, &packet);
	416	devc->num_samples++;
	417	}
	418	g_free(analog->data);
	419	g_free(analog);
	420	}
	421
ba6383f8	422	static void handle_new_data(struct dev_context *devc, int fd)
d375b3c3 AG	423	{
d375b3c3 AG	424	int len;
ba6383f8 UH	425	size_t i, offset = 0;
	426	struct rs_22_812_packet *rs_packet;
	427
	428	/* Try to get as much data as the buffer can hold. */
d375b3c3 AG	429	len = RS_DMM_BUFSIZE - devc->buflen;
	430	len = serial_read(fd, devc->buf + devc->buflen, len);
	431	if (len < 1) {
ba6383f8	432	sr_err("Serial port read error.");
d375b3c3 AG	433	return;
	434	}
	435	devc->buflen += len;
	436
ba6383f8 UH	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);
d375b3c3 AG	442	offset += RS_22_812_PACKET_SIZE;
	443	} else {
	444	offset++;
	445	}
	446	}
	447
ba6383f8 UH	448	/* If we have any data left, move it to the beginning of our buffer. */
ba6383f8 UH	449	for (i = 0; i < devc->buflen - offset; i++)
d375b3c3 AG	450	devc->buf[i] = devc->buf[offset + i];
	451	devc->buflen -= offset;
	452	}
	453
ba6383f8	454	SR_PRIV int radioshack_dmm_receive_data(int fd, int revents, void *cb_data)
d375b3c3	455	{
642e9d62	456	struct sr_dev_inst *sdi;
d375b3c3 AG	457	struct dev_context *devc;
	458
	459	if (!(sdi = cb_data))
	460	return TRUE;
	461
	462	if (!(devc = sdi->priv))
	463	return TRUE;
	464
ba6383f8	465	if (revents == G_IO_IN) {
d375b3c3 AG	466	/* Serial data arrived. */
	467	handle_new_data(devc, fd);
	468	}
	469
	470	if (devc->num_samples >= devc->limit_samples) {
	471	sdi->driver->dev_acquisition_stop(sdi, cb_data);
	472	return TRUE;
	473	}
	474
	475	return TRUE;
	476	}