libsigrok/hardware/common/dmm/es51922.c

434 lines
12 KiB
C

/*
* This file is part of the libsigrok project.
*
* Copyright (C) 2012 Uwe Hermann <uwe@hermann-uwe.de>
*
* 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
*/
/*
* Cyrustek ES51922 protocol parser.
*
* Communication parameters: Unidirectional, 19230/7o1
*/
#include <string.h>
#include <ctype.h>
#include <math.h>
#include <glib.h>
#include "libsigrok.h"
#include "libsigrok-internal.h"
/* Message logging helpers with subsystem-specific prefix string. */
#define LOG_PREFIX "es51922: "
#define sr_log(l, s, args...) sr_log(l, LOG_PREFIX s, ## args)
#define sr_spew(s, args...) sr_spew(LOG_PREFIX s, ## args)
#define sr_dbg(s, args...) sr_dbg(LOG_PREFIX s, ## args)
#define sr_info(s, args...) sr_info(LOG_PREFIX s, ## args)
#define sr_warn(s, args...) sr_warn(LOG_PREFIX s, ## args)
#define sr_err(s, args...) sr_err(LOG_PREFIX s, ## args)
/* Factors for the respective measurement mode (0 means "invalid"). */
static const float factors[8][8] = {
{1e-4, 1e-3, 1e-2, 1e-1, 1e-5, 0, 0, 0}, /* V */
{1e-8, 1e-7, 0, 0, 0, 0, 0, 0}, /* uA */
{1e-6, 1e-5, 0, 0, 0, 0, 0, 0}, /* mA */
{1e-3, 0, 0, 0, 0, 0, 0, 0}, /* 22A */
{1e-4, 1e-3, 1e-2, 1e-1, 1, 0, 0, 0}, /* Manual A */
{1e-2, 1e-1, 1, 1e1, 1e2, 1e3, 1e4, 0}, /* Resistance */
{1e-2, 1e-1, 0, 1, 1e1, 1e2, 1e3, 1e4}, /* Frequency */
{1e-12, 1e-11, 1e-10, 1e-9, 1e-8, 1e-7, 1e-6, 1e-5}, /* Capacitance */
};
static int parse_value(const uint8_t *buf, float *result)
{
int sign, intval;
float floatval;
/*
* Bytes 1-5: Value (5 decimal digits)
*
* Over limit: "0L." on the display, "22580" as protocol "digits".
* (chip max. value is 22000, so 22580 is out of range)
*
* Example: "OL.", auto-range mega-ohm mode
* Hex: 36 32 32 35 38 30 33 31 30 30 32 30 0d 0a
* ASCII: 2 2 5 8 0
*/
if (!strncmp((const char *)&buf[1], "22580", 5)) {
sr_spew("Over limit.");
*result = INFINITY;
return SR_OK;
} else if (!isdigit(buf[1]) || !isdigit(buf[2]) ||
!isdigit(buf[3]) || !isdigit(buf[4]) || !isdigit(buf[5])) {
sr_err("Value contained invalid digits: %02x %02x %02x %02x "
"%02x (%c %c %c %c %c).",
buf[1], buf[2], buf[3], buf[4], buf[5]);
return SR_ERR;
}
intval = 0;
intval += (buf[1] - '0') * 10000;
intval += (buf[2] - '0') * 1000;
intval += (buf[3] - '0') * 100;
intval += (buf[4] - '0') * 10;
intval += (buf[5] - '0') * 1;
floatval = (float)intval;
/* Note: The decimal point position will be parsed later. */
/* Byte 7: Sign bit (and other stuff) */
sign = ((buf[7] & (1 << 2)) != 0) ? -1 : 1;
/* Apply sign. */
floatval *= sign;
sr_spew("The display value is %f.", floatval);
*result = floatval;
return SR_OK;
}
static int parse_range(uint8_t b, float *floatval,
const struct es51922_info *info)
{
int idx, mode;
idx = b - '0';
if (!(idx >= 0 && idx <= 7)) {
sr_dbg("Invalid range byte / index: 0x%02x / 0x%02x.", b, idx);
return SR_ERR;
}
/* Parse range byte (depends on the measurement mode). */
if (info->is_voltage)
mode = 0; /* V */
else if (info->is_current && info->is_micro)
mode = 1; /* uA */
else if (info->is_current && info->is_milli)
mode = 2; /* mA */
else if (info->is_current && !info->is_micro && !info->is_milli)
mode = 3; /* 22A */
else if (info->is_current && !info->is_auto)
mode = 4; /* Manual A */
else if (info->is_resistance)
mode = 5; /* Resistance */
else if (info->is_frequency)
mode = 6; /* Frequency */
else if (info->is_capacitance)
mode = 7; /* Capacitance */
else {
sr_dbg("Invalid mode, range byte was: 0x%02x.", b);
return SR_ERR;
}
if (factors[mode][idx] == 0) {
sr_dbg("Invalid factor for range byte: 0x%02x.", b);
return SR_ERR;
}
/* Apply respective factor (mode-dependent) on the value. */
*floatval *= factors[mode][idx];
sr_dbg("Applying factor %f, new value is %f.",
factors[mode][idx], *floatval);
return SR_OK;
}
static void parse_flags(const uint8_t *buf, struct es51922_info *info)
{
/* Get is_judge and is_vbar early on, we'll need it. */
info->is_judge = (buf[7] & (1 << 3)) != 0;
info->is_vbar = (buf[11] & (1 << 2)) != 0;
/* Byte 6: Function */
switch (buf[6]) {
case 0x3b: /* V */
info->is_voltage = TRUE;
break;
case 0x3d: /* uA */
info->is_auto = info->is_micro = info->is_current = TRUE;
break;
case 0x3f: /* mA */
info->is_auto = info->is_milli = info->is_current = TRUE;
break;
case 0x30: /* 22A */
info->is_current = TRUE;
break;
case 0x39: /* Manual A */
info->is_auto = FALSE; /* Manual mode */
info->is_current = TRUE;
break;
case 0x33: /* Resistance */
info->is_resistance = TRUE;
break;
case 0x35: /* Continuity */
info->is_continuity = TRUE;
break;
case 0x31: /* Diode */
info->is_diode = TRUE;
break;
case 0x32: /* Frequency / duty cycle */
if (info->is_judge)
info->is_frequency = TRUE;
else
info->is_duty_cycle = TRUE;
break;
case 0x36: /* Capacitance */
info->is_capacitance = TRUE;
break;
case 0x34: /* Temperature */
info->is_temperature = TRUE;
if (info->is_judge)
info->is_celsius = TRUE;
else
info->is_fahrenheit = TRUE;
/* IMPORTANT: The digits always represent Celsius! */
break;
case 0x3e: /* ADP */
info->is_adp = TRUE;
break;
default:
sr_err("Invalid function byte: 0x%02x.", buf[6]);
break;
}
/* Byte 7: Status */
/* Bits [6:4]: Always 0b011 */
info->is_judge = (buf[7] & (1 << 3)) != 0;
info->is_sign = (buf[7] & (1 << 2)) != 0;
info->is_batt = (buf[7] & (1 << 1)) != 0; /* Battery low */
info->is_ol = (buf[7] & (1 << 0)) != 0; /* Input overflow */
/* Byte 8: Option 1 */
/* Bits [6:4]: Always 0b011 */
info->is_max = (buf[8] & (1 << 3)) != 0;
info->is_min = (buf[8] & (1 << 2)) != 0;
info->is_rel = (buf[8] & (1 << 1)) != 0;
info->is_rmr = (buf[8] & (1 << 0)) != 0;
/* Byte 9: Option 2 */
/* Bits [6:4]: Always 0b011 */
info->is_ul = (buf[9] & (1 << 3)) != 0;
info->is_pmax = (buf[9] & (1 << 2)) != 0; /* Max. peak value */
info->is_pmin = (buf[9] & (1 << 1)) != 0; /* Min. peak value */
/* Bit 0: Always 0 */
/* Byte 10: Option 3 */
/* Bits [6:4]: Always 0b011 */
info->is_dc = (buf[10] & (1 << 3)) != 0;
info->is_ac = (buf[10] & (1 << 2)) != 0;
info->is_auto = (buf[10] & (1 << 1)) != 0;
info->is_vahz = (buf[10] & (1 << 0)) != 0;
/* Byte 11: Option 4 */
/* Bits [6:3]: Always 0b0110 */
info->is_vbar = (buf[11] & (1 << 2)) != 0;
info->is_hold = (buf[11] & (1 << 1)) != 0;
info->is_lpf = (buf[11] & (1 << 0)) != 0; /* Low pass filter on */
/* Byte 12: Always '\r' (carriage return, 0x0d, 13) */
/* Byte 13: Always '\n' (newline, 0x0a, 10) */
}
static void handle_flags(struct sr_datafeed_analog *analog,
float *floatval, const struct es51922_info *info)
{
/*
* Note: is_micro etc. are not used directly to multiply/divide
* floatval, this is handled via parse_range() and factors[][].
*/
/* Measurement modes */
if (info->is_voltage) {
analog->mq = SR_MQ_VOLTAGE;
analog->unit = SR_UNIT_VOLT;
}
if (info->is_current) {
analog->mq = SR_MQ_CURRENT;
analog->unit = SR_UNIT_AMPERE;
}
if (info->is_resistance) {
analog->mq = SR_MQ_RESISTANCE;
analog->unit = SR_UNIT_OHM;
}
if (info->is_frequency) {
analog->mq = SR_MQ_FREQUENCY;
analog->unit = SR_UNIT_HERTZ;
}
if (info->is_capacitance) {
analog->mq = SR_MQ_CAPACITANCE;
analog->unit = SR_UNIT_FARAD;
}
if (info->is_temperature && info->is_celsius) {
analog->mq = SR_MQ_TEMPERATURE;
analog->unit = SR_UNIT_CELSIUS;
}
if (info->is_temperature && info->is_fahrenheit) {
analog->mq = SR_MQ_TEMPERATURE;
analog->unit = SR_UNIT_FAHRENHEIT;
}
if (info->is_continuity) {
analog->mq = SR_MQ_CONTINUITY;
analog->unit = SR_UNIT_BOOLEAN;
*floatval = (*floatval < 0.0) ? 0.0 : 1.0;
}
if (info->is_diode) {
analog->mq = SR_MQ_VOLTAGE;
analog->unit = SR_UNIT_VOLT;
}
if (info->is_duty_cycle) {
analog->mq = SR_MQ_DUTY_CYCLE;
analog->unit = SR_UNIT_PERCENTAGE;
}
/* Measurement related flags */
if (info->is_ac)
analog->mqflags |= SR_MQFLAG_AC;
if (info->is_dc)
analog->mqflags |= SR_MQFLAG_DC;
if (info->is_auto)
analog->mqflags |= SR_MQFLAG_AUTORANGE;
if (info->is_diode)
analog->mqflags |= SR_MQFLAG_DIODE;
if (info->is_hold)
/*
* Note: HOLD only affects the number displayed on the LCD,
* but not the value sent via the protocol! It also does not
* affect the bargraph on the LCD.
*/
analog->mqflags |= SR_MQFLAG_HOLD;
if (info->is_max)
analog->mqflags |= SR_MQFLAG_MAX;
if (info->is_min)
analog->mqflags |= SR_MQFLAG_MIN;
if (info->is_rel)
analog->mqflags |= SR_MQFLAG_RELATIVE;
/* Other flags */
if (info->is_judge)
sr_spew("Judge bit is set.");
if (info->is_batt)
sr_spew("Battery is low.");
if (info->is_ol)
sr_spew("Input overflow.");
if (info->is_pmax)
sr_spew("pMAX active, LCD shows max. peak value.");
if (info->is_pmin)
sr_spew("pMIN active, LCD shows min. peak value.");
if (info->is_vahz)
sr_spew("VAHZ active.");
if (info->is_vbar)
sr_spew("VBAR active.");
if (info->is_lpf)
sr_spew("Low-pass filter feature is active.");
}
static gboolean flags_valid(const struct es51922_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;
/* Note: No 'kilo' or 'mega' bits per se in this protocol. */
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_voltage) ? 1 : 0;
count += (info->is_current) ? 1 : 0;
count += (info->is_resistance) ? 1 : 0;
count += (info->is_frequency) ? 1 : 0;
count += (info->is_capacitance) ? 1 : 0;
count += (info->is_temperature) ? 1 : 0;
count += (info->is_continuity) ? 1 : 0;
count += (info->is_diode) ? 1 : 0;
count += (info->is_duty_cycle) ? 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_es51922_packet_valid(const uint8_t *buf)
{
struct es51922_info info;
memset(&info, 0x00, sizeof(struct es51922_info));
parse_flags(buf, &info);
if (!flags_valid(&info))
return FALSE;
if (buf[12] != '\r' || buf[13] != '\n') {
sr_spew("Packet doesn't end with \\r\\n.");
return FALSE;
}
return TRUE;
}
/**
* Parse a protocol packet.
*
* @param buf Buffer containing the protocol packet. Must not be NULL.
* @param floatval Pointer to a float variable. That variable will contain the
* result value upon parsing success. Must not be NULL.
* @param analog Pointer to a struct sr_datafeed_analog. The struct will be
* filled with data according to the protocol packet.
* Must not be NULL.
* @param info Pointer to a struct es51922_info. The struct will be filled
* with data according to the protocol packet. Must not be NULL.
*
* @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_es51922_parse(const uint8_t *buf, float *floatval,
struct sr_datafeed_analog *analog, void *info)
{
int ret;
struct es51922_info *info_local;
info_local = (struct es51922_info *)info;
if ((ret = parse_value(buf, floatval)) != SR_OK) {
sr_err("Error parsing value: %d.", ret);
return ret;
}
memset(info_local, 0x00, sizeof(struct es51922_info));
parse_flags(buf, info_local);
handle_flags(analog, floatval, info_local);
return parse_range(buf[0], floatval, info_local);
}