libsigrok/hardware/common/dmm/fs9721.c

431 lines
11 KiB
C

/*
* This file is part of the libsigrok project.
*
* Copyright (C) 2012 Uwe Hermann <uwe@hermann-uwe.de>
* 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 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
*/
/*
* Fortune Semiconductor FS9721_LP3/FS9721B protocol parser.
*
* FS9721_LP3: 4000 counts (3 3/4 digits)
* FS9721B/Q100: 2400 counts (3 2/3 digits)
*
* Same for both chips:
* - Packages: Bare die (78 pins) or QFP-100
* - Communication parameters: Unidirectional, 2400/8n1
* - The protocol seems to be exactly the same.
*/
#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 "fs9721: "
#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)
static int parse_digit(uint8_t b)
{
switch (b) {
case 0x7d:
return 0;
case 0x05:
return 1;
case 0x5b:
return 2;
case 0x1f:
return 3;
case 0x27:
return 4;
case 0x3e:
return 5;
case 0x7e:
return 6;
case 0x15:
return 7;
case 0x7f:
return 8;
case 0x3f:
return 9;
default:
sr_err("Invalid digit byte: 0x%02x.", b);
return -1;
}
}
static gboolean sync_nibbles_valid(const uint8_t *buf)
{
int i;
/* Check the synchronization nibbles, and make sure they all match. */
for (i = 0; i < FS9721_PACKET_SIZE; i++) {
if (((buf[i] >> 4) & 0x0f) != (i + 1)) {
sr_err("Sync nibble in byte %d (0x%02x) is invalid.",
i, buf[i]);
return FALSE;
}
}
return TRUE;
}
static gboolean flags_valid(const struct fs9721_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_hz) ? 1 : 0;
count += (info->is_ohm) ? 1 : 0;
count += (info->is_farad) ? 1 : 0;
count += (info->is_ampere) ? 1 : 0;
count += (info->is_volt) ? 1 : 0;
count += (info->is_percent) ? 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;
}
/* RS232 flag not set? */
if (!info->is_rs232) {
sr_err("No RS232 flag detected in packet.");
return FALSE;
}
return TRUE;
}
static int parse_value(const uint8_t *buf, float *result)
{
int i, sign, intval = 0, digits[4];
uint8_t digit_bytes[4];
float floatval;
/* Byte 1: LCD SEG2 */
sign = ((buf[1] & (1 << 3)) != 0) ? -1 : 1;
/*
* Bytes 1-8: Value (4 decimal digits, sign, decimal point)
*
* Over limit: "0L" (LCD), 0x00 0x7d 0x68 0x00 (digit bytes).
*/
/* Merge the two nibbles for a digit into one byte. */
for (i = 0; i < 4; i++) {
digit_bytes[i] = ((buf[1 + (i * 2)] & 0x0f) << 4);
digit_bytes[i] |= (buf[1 + (i * 2) + 1] & 0x0f);
/* Bit 7 in the byte is not part of the digit. */
digit_bytes[i] &= ~(1 << 7);
}
/* Check for "OL". */
if (digit_bytes[0] == 0x00 && digit_bytes[1] == 0x7d &&
digit_bytes[2] == 0x68 && digit_bytes[3] == 0x00) {
sr_spew("Over limit.");
*result = INFINITY;
return SR_OK;
}
/* Parse the digits. */
for (i = 0; i < 4; i++)
digits[i] = parse_digit(digit_bytes[i]);
sr_spew("Digits: %02x %02x %02x %02x (%d%d%d%d).",
digit_bytes[0], digit_bytes[1], digit_bytes[2], digit_bytes[3],
digits[0], digits[1], digits[2], digits[3]);
/* Merge all digits into an integer value. */
for (i = 0; i < 4; i++) {
intval *= 10;
intval += digits[i];
}
floatval = (float)intval;
/* Decimal point position. */
if ((buf[3] & (1 << 3)) != 0) {
floatval /= 1000;
sr_spew("Decimal point after first digit.");
} else if ((buf[5] & (1 << 3)) != 0) {
floatval /= 100;
sr_spew("Decimal point after second digit.");
} else if ((buf[7] & (1 << 3)) != 0) {
floatval /= 10;
sr_spew("Decimal point after third digit.");
} else {
sr_spew("No decimal point in the number.");
}
/* Apply sign. */
floatval *= sign;
sr_spew("The display value is %f.", floatval);
*result = floatval;
return SR_OK;
}
static void parse_flags(const uint8_t *buf, struct fs9721_info *info)
{
/* Byte 0: LCD SEG1 */
info->is_ac = (buf[0] & (1 << 3)) != 0;
info->is_dc = (buf[0] & (1 << 2)) != 0;
info->is_auto = (buf[0] & (1 << 1)) != 0;
info->is_rs232 = (buf[0] & (1 << 0)) != 0;
/* Byte 1: LCD SEG2 */
info->is_sign = (buf[1] & (1 << 3)) != 0;
/* Byte 9: LCD SEG10 */
info->is_micro = (buf[9] & (1 << 3)) != 0;
info->is_nano = (buf[9] & (1 << 2)) != 0;
info->is_kilo = (buf[9] & (1 << 1)) != 0;
info->is_diode = (buf[9] & (1 << 0)) != 0;
/* Byte 10: LCD SEG11 */
info->is_milli = (buf[10] & (1 << 3)) != 0;
info->is_percent = (buf[10] & (1 << 2)) != 0;
info->is_mega = (buf[10] & (1 << 1)) != 0;
info->is_beep = (buf[10] & (1 << 0)) != 0;
/* Byte 11: LCD SEG12 */
info->is_farad = (buf[11] & (1 << 3)) != 0;
info->is_ohm = (buf[11] & (1 << 2)) != 0;
info->is_rel = (buf[11] & (1 << 1)) != 0;
info->is_hold = (buf[11] & (1 << 0)) != 0;
/* Byte 12: LCD SEG13 */
info->is_ampere = (buf[12] & (1 << 3)) != 0;
info->is_volt = (buf[12] & (1 << 2)) != 0;
info->is_hz = (buf[12] & (1 << 1)) != 0;
info->is_bat = (buf[12] & (1 << 0)) != 0;
/* Byte 13: LCD SEG14 */
info->is_c2c1_11 = (buf[13] & (1 << 3)) != 0;
info->is_c2c1_10 = (buf[13] & (1 << 2)) != 0;
info->is_c2c1_01 = (buf[13] & (1 << 1)) != 0;
info->is_c2c1_00 = (buf[13] & (1 << 0)) != 0;
}
static void handle_flags(struct sr_datafeed_analog *analog, float *floatval,
const struct fs9721_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_hz) {
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_beep) {
analog->mq = SR_MQ_CONTINUITY;
analog->unit = SR_UNIT_BOOLEAN;
*floatval = (*floatval == INFINITY) ? 0.0 : 1.0;
}
if (info->is_diode) {
analog->mq = SR_MQ_VOLTAGE;
analog->unit = SR_UNIT_VOLT;
}
if (info->is_percent) {
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)
analog->mqflags |= SR_MQFLAG_HOLD;
if (info->is_rel)
analog->mqflags |= SR_MQFLAG_RELATIVE;
/* Other flags */
if (info->is_rs232)
sr_spew("RS232 enabled.");
if (info->is_bat)
sr_spew("Battery is low.");
if (info->is_c2c1_00)
sr_spew("User-defined LCD symbol 0 is active.");
if (info->is_c2c1_01)
sr_spew("User-defined LCD symbol 1 is active.");
if (info->is_c2c1_10)
sr_spew("User-defined LCD symbol 2 is active.");
if (info->is_c2c1_11)
sr_spew("User-defined LCD symbol 3 is active.");
}
SR_PRIV gboolean sr_fs9721_packet_valid(const uint8_t *buf)
{
struct fs9721_info info;
parse_flags(buf, &info);
return (sync_nibbles_valid(buf) && flags_valid(&info));
}
/**
* Parse a protocol packet.
*
* @param buf Buffer containing the 14-byte protocol packet. Must not be NULL.
* @param floatval Pointer to a float variable. That variable will contain the
* result value upon parsing success. Mut 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 fs9721_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_fs9721_parse(const uint8_t *buf, float *floatval,
struct sr_datafeed_analog *analog, void *info)
{
int ret;
struct fs9721_info *info_local;
info_local = (struct fs9721_info *)info;
if ((ret = parse_value(buf, floatval)) != SR_OK) {
sr_err("Error parsing value: %d.", ret);
return ret;
}
parse_flags(buf, info_local);
handle_flags(analog, floatval, info_local);
return SR_OK;
}
SR_PRIV void sr_fs9721_00_temp_c(struct sr_datafeed_analog *analog, void *info)
{
struct fs9721_info *info_local;
info_local = (struct fs9721_info *)info;
/* User-defined FS9721_LP3 flag 'c2c1_00' means temperature (C). */
if (info_local->is_c2c1_00) {
analog->mq = SR_MQ_TEMPERATURE;
analog->unit = SR_UNIT_CELSIUS;
}
}
SR_PRIV void sr_fs9721_01_temp_c(struct sr_datafeed_analog *analog, void *info)
{
struct fs9721_info *info_local;
info_local = (struct fs9721_info *)info;
/* User-defined FS9721_LP3 flag 'c2c1_01' means temperature (C). */
if (info_local->is_c2c1_01) {
analog->mq = SR_MQ_TEMPERATURE;
analog->unit = SR_UNIT_CELSIUS;
}
}
SR_PRIV void sr_fs9721_10_temp_c(struct sr_datafeed_analog *analog, void *info)
{
struct fs9721_info *info_local;
info_local = (struct fs9721_info *)info;
/* User-defined FS9721_LP3 flag 'c2c1_10' means temperature (C). */
if (info_local->is_c2c1_10) {
analog->mq = SR_MQ_TEMPERATURE;
analog->unit = SR_UNIT_CELSIUS;
}
}
SR_PRIV void sr_fs9721_01_10_temp_f_c(struct sr_datafeed_analog *analog, void *info)
{
struct fs9721_info *info_local;
info_local = (struct fs9721_info *)info;
/* User-defined FS9721_LP3 flag 'c2c1_01' means temperature (F). */
if (info_local->is_c2c1_01) {
analog->mq = SR_MQ_TEMPERATURE;
analog->unit = SR_UNIT_FAHRENHEIT;
}
/* User-defined FS9721_LP3 flag 'c2c1_10' means temperature (C). */
if (info_local->is_c2c1_10) {
analog->mq = SR_MQ_TEMPERATURE;
analog->unit = SR_UNIT_CELSIUS;
}
}