# Backend files
libsigrok_la_SOURCES = \
src/backend.c \
+ src/conversion.c \
src/device.c \
src/session.c \
src/session_file.c \
return QuantityFlag::flags_from_mask(_structure->meaning->mqflags);
}
+shared_ptr<Logic> Analog::get_logic_via_threshold(float threshold,
+ uint8_t *data_ptr) const
+{
+ auto datafeed = g_new(struct sr_datafeed_logic, 1);
+ datafeed->length = num_samples();
+ datafeed->unitsize = 1;
+
+ if (data_ptr)
+ datafeed->data = data_ptr;
+ else
+ datafeed->data = g_malloc(datafeed->length);
+
+ shared_ptr<Logic> logic =
+ shared_ptr<Logic>{new Logic{datafeed}, default_delete<Logic>{}};
+
+ check(sr_a2l_threshold(_structure, threshold,
+ (uint8_t*)datafeed->data, datafeed->length));
+
+ return logic;
+}
+
+shared_ptr<Logic> Analog::get_logic_via_schmitt_trigger(float lo_thr,
+ float hi_thr, uint8_t *state, uint8_t *data_ptr) const
+{
+ auto datafeed = g_new(struct sr_datafeed_logic, 1);
+ datafeed->length = num_samples();
+ datafeed->unitsize = 1;
+
+ if (data_ptr)
+ datafeed->data = data_ptr;
+ else
+ datafeed->data = g_malloc(datafeed->length);
+
+ shared_ptr<Logic> logic =
+ shared_ptr<Logic>{new Logic{datafeed}, default_delete<Logic>{}};
+
+ check(sr_a2l_schmitt_trigger(_structure, lo_thr, hi_thr, state,
+ (uint8_t*)datafeed->data, datafeed->length));
+
+ return logic;
+}
+
Rational::Rational(const struct sr_rational *structure) :
_structure(structure)
{
const struct sr_datafeed_logic *_structure;
friend class Packet;
+ friend class Analog;
+ friend struct std::default_delete<Logic>;
};
/** Payload of a datafeed packet with analog data */
const Unit *unit() const;
/** Measurement flags associated with the samples in this packet. */
vector<const QuantityFlag *> mq_flags() const;
+ /**
+ * Provides a Logic packet that contains a conversion of the analog
+ * data using a simple threshold.
+ *
+ * @param threshold Threshold to use.
+ * @param data_ptr Pointer to num_samples() bytes where the logic
+ * samples are stored. When nullptr, memory for
+ * logic->data_pointer() will be allocated and must
+ * be freed by the caller.
+ */
+ shared_ptr<Logic> get_logic_via_threshold(float threshold,
+ uint8_t *data_ptr=nullptr) const;
+ /**
+ * Provides a Logic packet that contains a conversion of the analog
+ * data using a Schmitt-Trigger.
+ *
+ * @param lo_thr Low threshold to use (anything below this is low).
+ * @param hi_thr High threshold to use (anything above this is high).
+ * @param state Points to a byte that contains the current state of the
+ * converter. For best results, set to value of logic
+ * sample n-1.
+ * @param data_ptr Pointer to num_samples() bytes where the logic
+ * samples are stored. When nullptr, memory for
+ * logic->data_pointer() will be allocated and must be
+ * freed by the caller.
+ */
+ shared_ptr<Logic> get_logic_via_schmitt_trigger(float lo_thr,
+ float hi_thr, uint8_t *state, uint8_t *data_ptr=nullptr) const;
private:
explicit Analog(const struct sr_datafeed_analog *structure);
~Analog();
SR_API char *sr_buildinfo_host_get(void);
SR_API char *sr_buildinfo_scpi_backends_get(void);
+/*--- conversion.c ----------------------------------------------------------*/
+
+SR_API int sr_a2l_threshold(const struct sr_datafeed_analog *analog,
+ float threshold, uint8_t *output, uint64_t count);
+SR_API int sr_a2l_schmitt_trigger(const struct sr_datafeed_analog *analog,
+ float lo_thr, float hi_thr, uint8_t *state, uint8_t *output,
+ uint64_t count);
+
/*--- log.c -----------------------------------------------------------------*/
typedef int (*sr_log_callback)(void *cb_data, int loglevel,
--- /dev/null
+/*
+ * This file is part of the libsigrok project.
+ *
+ * Copyright (C) 2017 Soeren Apel <soeren@apelpie.net>
+ *
+ * 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/>.
+ */
+
+/**
+ * @file
+ *
+ * Conversion helper functions.
+ */
+
+#include <libsigrok/libsigrok.h>
+#include "libsigrok-internal.h"
+
+#define LOG_PREFIX "conv"
+
+/**
+ * Convert analog values to logic values by using a fixed threshold.
+ *
+ * @param[in] analog The analog input values.
+ * @param[in] threshold The threshold to use.
+ * @param[out] output The converted output values; either 0 or 1. Must provide
+ * space for count bytes.
+ * @param[in] count The number of samples to process.
+ *
+ * @return SR_OK on success or SR_ERR on failure.
+ */
+SR_API int sr_a2l_threshold(const struct sr_datafeed_analog *analog,
+ float threshold, uint8_t *output, uint64_t count)
+{
+ float *input;
+
+ if (!analog->encoding->is_float) {
+ input = g_try_malloc(sizeof(float) * count);
+ if (!input)
+ return SR_ERR;
+
+ sr_analog_to_float(analog, input);
+ } else
+ input = analog->data;
+
+ for (uint64_t i = 0; i < count; i++)
+ output[i] = (input[i] >= threshold) ? 1 : 0;
+
+ if (!analog->encoding->is_float)
+ g_free(input);
+
+ return SR_OK;
+}
+
+/**
+ * Convert analog values to logic values by using a Schmitt-trigger algorithm.
+ *
+ * @param analog The analog input values.
+ * @param lo_thr The low threshold - result becomes 0 below it.
+ * @param lo_thr The high threshold - result becomes 1 above it.
+ * @param state The internal converter state. Must contain the state of logic
+ * sample n-1, will contain the state of logic sample n+count upon exit.
+ * @param output The converted output values; either 0 or 1. Must provide
+ * space for count bytes.
+ * @param count The number of samples to process.
+ *
+ * @return SR_OK on success or SR_ERR on failure.
+ */
+SR_API int sr_a2l_schmitt_trigger(const struct sr_datafeed_analog *analog,
+ float lo_thr, float hi_thr, uint8_t *state, uint8_t *output,
+ uint64_t count)
+{
+ float *input;
+
+ if (!analog->encoding->is_float) {
+ input = g_try_malloc(sizeof(float) * count);
+ if (!input)
+ return SR_ERR;
+
+ sr_analog_to_float(analog, input);
+ } else
+ input = analog->data;
+
+ for (uint64_t i = 0; i < count; i++) {
+ if (input[i] < lo_thr)
+ *state = 0;
+ else if (input[i] > hi_thr)
+ *state = 1;
+
+ output[i] = *state;
+ }
+
+ if (!analog->encoding->is_float)
+ g_free(input);
+
+ return SR_OK;
+}
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