--- /dev/null
+/*
+ * This file is part of the libsigrok project.
+ *
+ * Copyright (C) 2015 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
+ */
+
+/*
+ * KERN scale protocol parser.
+ */
+
+#include <string.h>
+#include <ctype.h>
+#include <math.h>
+#include <glib.h>
+#include <libsigrok/libsigrok.h>
+#include "libsigrok-internal.h"
+
+#define LOG_PREFIX "kern"
+
+static int get_buflen(const uint8_t *buf)
+{
+ /* Find out whether it's a 14-byte or 15-byte packet. */
+ if (buf[12] == '\r' && buf[13] == '\n')
+ return 14;
+ else if (buf[13] == '\r' && buf[14] == '\n')
+ return 15;
+ else
+ return -1;
+}
+
+static int parse_value(const uint8_t *buf, float *result,
+ const struct kern_info *info)
+{
+ char *strval;
+ float floatval;
+ int s2, len;
+
+ s2 = (info->buflen == 14) ? 11 : 12;
+ len = (info->buflen == 14) ? 8 : 9;
+
+ if (buf[s2] == 'E') {
+ /* Display: "o-Err" or "u-Err", but protocol only has 'E'. */
+ sr_spew("Over/under limit.");
+ *result = INFINITY;
+ return SR_OK;
+ }
+
+ strval = g_strndup((const char *)buf, len);
+ floatval = g_ascii_strtod(strval, NULL);
+ g_free(strval);
+ *result = floatval;
+
+ return SR_OK;
+}
+
+static void parse_flags(const uint8_t *buf, struct kern_info *info)
+{
+ int u1, u2, s2;
+
+ u1 = (info->buflen == 14) ? 8 : 9;
+ u2 = (info->buflen == 14) ? 9 : 10;
+ s2 = (info->buflen == 14) ? 11 : 12;
+
+ /* Bytes U1, U2: Unit */
+ info->is_gram = (buf[u1] == ' ' && buf[u2] == 'G');
+ info->is_carat = (buf[u1] == 'C' && buf[u2] == 'T');
+ info->is_ounce = (buf[u1] == 'O' && buf[u2] == 'Z');
+ info->is_pound = (buf[u1] == 'L' && buf[u2] == 'B');
+ info->is_troy_ounce = (buf[u1] == 'O' && buf[u2] == 'T');
+ info->is_pennyweight = (buf[u1] == 'D' && buf[u2] == 'W');
+ info->is_grain = (buf[u1] == 'G' && buf[u2] == 'R');
+ info->is_tael = (buf[u1] == 'T' && buf[u2] == 'L');
+ info->is_momme = (buf[u1] == 'M' && buf[u2] == 'O');
+ info->is_tola = (buf[u1] == 't' && buf[u2] == 'o');
+ info->is_percentage = (buf[u1] == ' ' && buf[u2] == '%');
+ info->is_piece = (buf[u1] == 'P' && buf[u2] == 'C');
+
+ /*
+ * Note: The display can show 3 different variants for Tael:
+ * "Hong Kong", "Singapore, Malaysia", and "Taiwan". However,
+ * in the protocol only one Tael value ('T', 'L') is used, thus
+ * we cannot distinguish between them.
+ */
+
+ /* Byte S1: Result / data type (currently unused) */
+
+ /* Byte S2: Status of the data */
+ info->is_unstable = (buf[s2] == 'U');
+ info->is_stable = (buf[s2] == 'S');
+ info->is_error = (buf[s2] == 'E');
+ /* Space: no special status. */
+
+ /* Byte CR: Always '\r' (carriage return, 0x0d, 13) */
+
+ /* Byte LF: Always '\n' (newline, 0x0a, 10) */
+}
+
+static void handle_flags(struct sr_datafeed_analog *analog, float *floatval,
+ const struct kern_info *info)
+{
+ (void)floatval;
+
+ /* Measured quantity: mass. */
+ analog->mq = SR_MQ_MASS;
+
+ /* Unit */
+ if (info->is_gram)
+ analog->unit = SR_UNIT_GRAM;
+ if (info->is_carat)
+ analog->unit = SR_UNIT_CARAT;
+ if (info->is_ounce)
+ analog->unit = SR_UNIT_OUNCE;
+ if (info->is_pound)
+ analog->unit = SR_UNIT_POUND;
+ if (info->is_troy_ounce)
+ analog->unit = SR_UNIT_TROY_OUNCE;
+ if (info->is_pennyweight)
+ analog->unit = SR_UNIT_PENNYWEIGHT;
+ if (info->is_grain)
+ analog->unit = SR_UNIT_GRAIN;
+ if (info->is_tael)
+ analog->unit = SR_UNIT_TAEL;
+ if (info->is_momme)
+ analog->unit = SR_UNIT_MOMME;
+ if (info->is_tola)
+ analog->unit = SR_UNIT_TOLA;
+ if (info->is_percentage)
+ analog->unit = SR_UNIT_PERCENTAGE;
+ if (info->is_piece)
+ analog->unit = SR_UNIT_PIECE;
+
+ /* Measurement related flags */
+ if (info->is_unstable)
+ analog->mqflags |= SR_MQFLAG_UNSTABLE;
+}
+
+SR_PRIV gboolean sr_kern_packet_valid(const uint8_t *buf)
+{
+ int buflen, s1, s2, cr, lf;
+
+ if ((buflen = get_buflen(buf)) < 0)
+ return FALSE;
+
+ s1 = (buflen == 14) ? 10 : 11;
+ s2 = (buflen == 14) ? 11 : 12;
+ cr = (buflen == 14) ? 12 : 13;
+ lf = (buflen == 14) ? 13 : 14;
+
+ /* Byte 0: Sign (must be '+' or '-' or ' '). */
+ if (buf[0] != '+' && buf[0] != '-' && buf[0] != ' ')
+ return FALSE;
+
+ /* Byte S1: Must be 'L' or 'G' or 'H' or ' '. */
+ if (buf[s1] != 'L' && buf[s1] != 'G' && buf[s1] != 'H' && buf[s1] != ' ')
+ return FALSE;
+
+ /* Byte S2: Must be 'U' or 'S' or 'E' or ' '. */
+ if (buf[s2] != 'U' && buf[s2] != 'S' && buf[s2] != 'E' && buf[s2] != ' ')
+ return FALSE;
+
+ /* Byte CR: Always '\r' (carriage return, 0x0d, 13) */
+ /* Byte LF: Always '\n' (newline, 0x0a, 10) */
+ if (buf[cr] != '\r' || buf[lf] != '\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 kern_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_kern_parse(const uint8_t *buf, float *floatval,
+ struct sr_datafeed_analog *analog, void *info)
+{
+ int ret;
+ struct kern_info *info_local;
+
+ info_local = (struct kern_info *)info;
+
+ info_local->buflen = get_buflen(buf);
+
+ if ((ret = parse_value(buf, floatval, info_local)) != SR_OK) {
+ sr_dbg("Error parsing value: %d.", ret);
+ return ret;
+ }
+
+ parse_flags(buf, info_local);
+ handle_flags(analog, floatval, info_local);
+
+ return SR_OK;
+}
projects / libsigrok.git / commitdiff