140 lines
3.1 KiB
C
140 lines
3.1 KiB
C
/*
|
|
* This file is part of the libsigrok project.
|
|
*
|
|
* Copyright (C) 2015 Martin Ling <martin-sigrok@earth.li>
|
|
*
|
|
* 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, see <http://www.gnu.org/licenses/>.
|
|
*/
|
|
|
|
/*
|
|
* UNI-T UT372 protocol parser.
|
|
*/
|
|
|
|
#include <config.h>
|
|
#include <stdlib.h>
|
|
#include <stdint.h>
|
|
#include <math.h>
|
|
#include <libsigrok/libsigrok.h>
|
|
#include "libsigrok-internal.h"
|
|
|
|
#define LOG_PREFIX "ut372"
|
|
|
|
static const uint8_t lookup[] = {
|
|
0x7B,
|
|
0x60,
|
|
0x5E,
|
|
0x7C,
|
|
0x65,
|
|
0x3D,
|
|
0x3F,
|
|
0x70,
|
|
0x7F,
|
|
0x7D,
|
|
};
|
|
|
|
#define DECIMAL_POINT_MASK 0x80
|
|
|
|
#define FLAGS1_HOLD_MASK (1 << 2)
|
|
|
|
#define FLAGS2_RPM_MASK (1 << 0)
|
|
#define FLAGS2_COUNT_MASK (1 << 1)
|
|
#define FLAGS2_MAX_MASK (1 << 4)
|
|
#define FLAGS2_MIN_MASK (1 << 5)
|
|
#define FLAGS2_AVG_MASK (1 << 6)
|
|
|
|
/* Decode a pair of characters into a byte. */
|
|
static uint8_t decode_pair(const uint8_t *buf)
|
|
{
|
|
unsigned int i;
|
|
char hex[3];
|
|
|
|
hex[2] = '\0';
|
|
|
|
for (i = 0; i < 2; i++) {
|
|
hex[i] = buf[i];
|
|
if (hex[i] > 0x39)
|
|
hex[i] += 7;
|
|
}
|
|
|
|
return strtol(hex, NULL, 16);
|
|
}
|
|
|
|
SR_PRIV gboolean sr_ut372_packet_valid(const uint8_t *buf)
|
|
{
|
|
uint8_t flags2;
|
|
|
|
if (!(buf[25] == '\r' && buf[26] == '\n'))
|
|
return FALSE;
|
|
|
|
flags2 = decode_pair(buf + 23);
|
|
|
|
if (!(flags2 & (FLAGS2_RPM_MASK | FLAGS2_COUNT_MASK)))
|
|
/* Device is in the setup menu - no valid data shown. */
|
|
return FALSE;
|
|
|
|
return TRUE;
|
|
}
|
|
|
|
SR_PRIV int sr_ut372_parse(const uint8_t *buf, float *floatval,
|
|
struct sr_datafeed_analog *analog, void *info)
|
|
{
|
|
unsigned int i, j, value;
|
|
uint8_t segments, flags1, flags2;
|
|
int exponent;
|
|
|
|
(void) info;
|
|
|
|
flags1 = decode_pair(buf + 21);
|
|
flags2 = decode_pair(buf + 23);
|
|
|
|
if (flags2 & FLAGS2_RPM_MASK) {
|
|
analog->meaning->mq = SR_MQ_FREQUENCY;
|
|
analog->meaning->unit = SR_UNIT_REVOLUTIONS_PER_MINUTE;
|
|
} else if (flags2 & FLAGS2_COUNT_MASK) {
|
|
analog->meaning->mq = SR_MQ_COUNT;
|
|
analog->meaning->unit = SR_UNIT_UNITLESS;
|
|
}
|
|
|
|
if (flags1 & FLAGS1_HOLD_MASK)
|
|
analog->meaning->mqflags |= SR_MQFLAG_HOLD;
|
|
if (flags2 & FLAGS2_MIN_MASK)
|
|
analog->meaning->mqflags |= SR_MQFLAG_MIN;
|
|
if (flags2 & FLAGS2_MAX_MASK)
|
|
analog->meaning->mqflags |= SR_MQFLAG_MAX;
|
|
if (flags2 & FLAGS2_AVG_MASK)
|
|
analog->meaning->mqflags |= SR_MQFLAG_AVG;
|
|
|
|
value = 0;
|
|
exponent = 0;
|
|
|
|
for (i = 0; i < 5; i++) {
|
|
segments = decode_pair(buf + 1 + (2 * i));
|
|
for (j = 0; j < ARRAY_SIZE(lookup); j++) {
|
|
if (lookup[j] == (segments & ~DECIMAL_POINT_MASK)) {
|
|
value += j * pow(10, i);
|
|
break;
|
|
}
|
|
}
|
|
if (segments & DECIMAL_POINT_MASK)
|
|
exponent = -i;
|
|
}
|
|
|
|
*floatval = (float) value * powf(10, exponent);
|
|
|
|
analog->encoding->digits = -exponent;
|
|
analog->spec->spec_digits = -exponent;
|
|
|
|
return SR_OK;
|
|
}
|