From: Uwe Hermann Date: Wed, 14 Nov 2012 17:38:26 +0000 (+0100) Subject: Add Metex 14-byte ASCII protocol parser. X-Git-Tag: dsupstream~538 X-Git-Url: https://sigrok.org/gitaction?a=commitdiff_plain;h=ac913e5c3522fcf5a5633eaa8e19f6579dda554c;p=libsigrok.git Add Metex 14-byte ASCII protocol parser. --- diff --git a/hardware/common/dmm/Makefile.am b/hardware/common/dmm/Makefile.am index ff434562..ee550270 100644 --- a/hardware/common/dmm/Makefile.am +++ b/hardware/common/dmm/Makefile.am @@ -22,7 +22,8 @@ noinst_LTLIBRARIES = libsigrok_hw_common_dmm.la libsigrok_hw_common_dmm_la_SOURCES = \ fs9721.c \ - fs9922.c + fs9922.c \ + metex14.c libsigrok_hw_common_dmm_la_CFLAGS = \ -I$(top_srcdir) diff --git a/hardware/common/dmm/metex14.c b/hardware/common/dmm/metex14.c new file mode 100644 index 00000000..9c6fd62e --- /dev/null +++ b/hardware/common/dmm/metex14.c @@ -0,0 +1,296 @@ +/* + * This file is part of the sigrok project. + * + * Copyright (C) 2012 Uwe Hermann + * + * 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 2 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, write to the Free Software + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + */ + +/* + * Metex 14-bytes ASCII protocol parser. + * + * This should work for various multimeters which use this kind of protocol, + * even though there is some variation in which modes each DMM supports. + * + * It does _not_ work for all Metex DMMs, some use a quite different protocol. + */ + +#include +#include +#include +#include +#include "libsigrok.h" +#include "libsigrok-internal.h" + +/* Message logging helpers with driver-specific prefix string. */ +#define DRIVER_LOG_DOMAIN "metex14: " +#define sr_log(l, s, args...) sr_log(l, DRIVER_LOG_DOMAIN s, ## args) +#define sr_spew(s, args...) sr_spew(DRIVER_LOG_DOMAIN s, ## args) +#define sr_dbg(s, args...) sr_dbg(DRIVER_LOG_DOMAIN s, ## args) +#define sr_info(s, args...) sr_info(DRIVER_LOG_DOMAIN s, ## args) +#define sr_warn(s, args...) sr_warn(DRIVER_LOG_DOMAIN s, ## args) +#define sr_err(s, args...) sr_err(DRIVER_LOG_DOMAIN s, ## args) + +static int parse_value(const uint8_t *buf, float *result) +{ + int i, sign, intval = 0, factor, decimal_point = 0, is_ol; + float floatval; + uint8_t digit; + + /* Byte 3: Sign (' ' or '-') */ + if (buf[3] == ' ') { + sign = 1; + } else if (buf[3] == '-') { + sign = -1; + } else { + sr_err("Invalid sign byte: 0x%02x.", buf[3]); + return SR_ERR; + } + + /* Bytes 5-7: Over limit (various forms) */ + is_ol = 0; + is_ol += !strncmp((char *)&buf[5], ".OL", 3); + is_ol += !strncmp((char *)&buf[5], "O.L", 3); + is_ol += !strncmp((char *)&buf[5], "OL.", 3); + is_ol += !strncmp((char *)&buf[5], " OL", 3); + if (is_ol != 0) { + sr_spew("Over limit."); + *result = INFINITY; + return SR_OK; + } + + /* Bytes 4-8: Value (up to 4 digits) and decimal point */ + factor = 1000; + for (i = 0; i < 5; i++) { + digit = buf[4 + i]; + if (digit == '.') { + decimal_point = i; + } else if (isdigit(digit)) { + intval += (digit - '0') * factor; + factor /= 10; + } else { + sr_err("Invalid digit byte: 0x%02x.", digit); + return SR_ERR; + } + } + + floatval = (float)intval; + + /* Decimal point position */ + if (decimal_point == 0 || decimal_point == 4) { + /* TODO: Doesn't happen? */ + } else if (decimal_point == 1) { + floatval /= 1000; + } else if (decimal_point == 2) { + floatval /= 100; + } else if (decimal_point == 3) { + floatval /= 10; + } else { + sr_err("Invalid decimal point position: %d.", decimal_point); + return SR_ERR; + } + + /* Apply sign. */ + floatval *= sign; + + sr_spew("The display value is %f.", floatval); + + *result = floatval; + + return SR_OK; +} + +static void parse_flags(const char *buf, struct metex14_info *info) +{ + /* Bytes 0-1: Measurement mode */ + /* Note: Protocol doesn't distinguish "resistance" from "beep" mode. */ + info->is_ac = !strncmp(buf, "AC", 2); + info->is_dc = !strncmp(buf, "DC", 2); + info->is_resistance = !strncmp(buf, "OH", 2); + info->is_capacity = !strncmp(buf, "CA", 2); + info->is_temperature = !strncmp(buf, "TE", 2); + info->is_diode = !strncmp(buf, "DI", 2); + info->is_frequency = !strncmp(buf, "FR", 2); + + if (info->is_dc || info->is_ac) + info->is_volt = TRUE; + + /* Byte 2: Always space (0x20). */ + + /* Bytes 3-8: See parse_value(). */ + + /* Bytes 9-12: Unit */ + if (!strcmp(buf + 9, " A")) + info->is_ampere = TRUE; + else if (!strcmp(buf + 9, " mA")) + info->is_milli = info->is_ampere = TRUE; + else if (!strcmp(buf + 9, " V")) + info->is_volt = TRUE; + else if (!strcmp(buf + 9, " mV")) + info->is_milli = info->is_volt = TRUE; + else if (!strcmp(buf + 9, " Ohm")) + info->is_ohm = TRUE; + else if (!strcmp(buf + 9, "KOhm")) + info->is_kilo = info->is_ohm = TRUE; + else if (!strcmp(buf + 9, "MOhm")) + info->is_mega = info->is_ohm = TRUE; + else if (!strcmp(buf + 9, " nF")) + info->is_nano = info->is_farad = TRUE; + else if (!strcmp(buf + 9, " uF")) + info->is_micro = info->is_farad = TRUE; + else if (!strcmp(buf + 9, " KHz")) + info->is_kilo = info->is_hertz = TRUE; + else if (!strcmp(buf + 9, " C")) + info->is_celsius = TRUE; + + /* Byte 13: Always '\r' (carriage return, 0x0d, 13) */ +} + +static void handle_flags(struct sr_datafeed_analog *analog, float *floatval, + const struct metex14_info *info) +{ + /* Factors */ + if (info->is_nano) + *floatval /= 1000000000; + if (info->is_micro) + *floatval /= 1000000; + if (info->is_milli) + *floatval /= 1000; + if (info->is_kilo) + *floatval *= 1000; + if (info->is_mega) + *floatval *= 1000000; + + /* Measurement modes */ + if (info->is_volt) { + analog->mq = SR_MQ_VOLTAGE; + analog->unit = SR_UNIT_VOLT; + } + if (info->is_ampere) { + analog->mq = SR_MQ_CURRENT; + analog->unit = SR_UNIT_AMPERE; + } + if (info->is_ohm) { + analog->mq = SR_MQ_RESISTANCE; + analog->unit = SR_UNIT_OHM; + } + if (info->is_hertz) { + analog->mq = SR_MQ_FREQUENCY; + analog->unit = SR_UNIT_HERTZ; + } + if (info->is_farad) { + analog->mq = SR_MQ_CAPACITANCE; + analog->unit = SR_UNIT_FARAD; + } + if (info->is_celsius) { + analog->mq = SR_MQ_TEMPERATURE; + analog->unit = SR_UNIT_CELSIUS; + } + if (info->is_diode) { + analog->mq = SR_MQ_VOLTAGE; + analog->unit = SR_UNIT_VOLT; + } + + /* Measurement related flags */ + if (info->is_ac) + analog->mqflags |= SR_MQFLAG_AC; + if (info->is_dc) + analog->mqflags |= SR_MQFLAG_DC; +} + +static gboolean flags_valid(const struct metex14_info *info) +{ + int count; + + /* Does the packet have more than one multiplier? */ + count = 0; + count += (info->is_nano) ? 1 : 0; + count += (info->is_micro) ? 1 : 0; + count += (info->is_milli) ? 1 : 0; + count += (info->is_kilo) ? 1 : 0; + count += (info->is_mega) ? 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 += (info->is_ac) ? 1 : 0; + count += (info->is_dc) ? 1 : 0; + count += (info->is_resistance) ? 1 : 0; + count += (info->is_capacity) ? 1 : 0; + count += (info->is_temperature) ? 1 : 0; + count += (info->is_diode) ? 1 : 0; + count += (info->is_frequency) ? 1 : 0; + if (count > 1) { + sr_err("More than one measurement type detected in packet."); + return FALSE; + } + + /* Both AC and DC set? */ + if (info->is_ac && info->is_dc) { + sr_err("Both AC and DC flags detected in packet."); + return FALSE; + } + + return TRUE; +} + +SR_PRIV gboolean sr_metex14_packet_valid(const uint8_t *buf) +{ + struct metex14_info info; + + memset(&info, 0x00, sizeof(struct metex14_info)); + parse_flags((const char *)buf, &info); + + if (!flags_valid(&info)) + return FALSE; + + if (buf[13] != '\r') + return FALSE; + + return TRUE; +} + +/** + * Parse a protocol packet. + * + * @param buf Buffer containing the protocol packet. + * @param floatval Pointer to a float variable. That variable will be modified + * in-place depending on the protocol packet. + * @param analog Pointer to a struct sr_datafeed_analog. The struct will be + * filled with data according to the protocol packet. + * + * @return SR_OK upon success, SR_ERR upon failure. Upon errors, the + * 'analog' variable contents are undefined and should not be used. + */ +SR_PRIV int sr_metex14_parse(const uint8_t *buf, float *floatval, + struct sr_datafeed_analog *analog, + struct metex14_info *info) +{ + int ret; + + if ((ret = parse_value(buf, floatval)) != SR_OK) { + sr_err("Error parsing value: %d.", ret); + return ret; + } + + memset(info, 0x00, sizeof(struct metex14_info)); + parse_flags((const char *)buf, info); + handle_flags(analog, floatval, info); + + return SR_OK; +} diff --git a/libsigrok-internal.h b/libsigrok-internal.h index e312ab70..d96803cb 100644 --- a/libsigrok-internal.h +++ b/libsigrok-internal.h @@ -184,4 +184,20 @@ SR_PRIV int sr_fs9721_parse(const uint8_t *buf, float *floatval, struct sr_datafeed_analog *analog, struct fs9721_info *info); +/*--- hardware/common/dmm/metex14.c -----------------------------------------*/ + +#define METEX14_PACKET_SIZE 14 + +struct metex14_info { + gboolean is_ac, is_dc, is_resistance, is_capacity, is_temperature; + gboolean is_diode, is_frequency, is_ampere, is_volt, is_farad; + gboolean is_hertz, is_ohm, is_celsius, is_nano, is_micro, is_milli; + gboolean is_kilo, is_mega; +}; + +SR_PRIV gboolean sr_metex14_packet_valid(const uint8_t *buf); +SR_PRIV int sr_metex14_parse(const uint8_t *buf, float *floatval, + struct sr_datafeed_analog *analog, + struct metex14_info *info); + #endif