X-Git-Url: https://git.rvb.name/rtl-433.git/blobdiff_plain/ca13278b24eb61443559bcb61e64627fba3d8823..6d15c6f967221af825cf84e3ed12b96c763b127b:/src/devices/efergy_e2_classic.c

diff --git a/src/devices/efergy_e2_classic.c b/src/devices/efergy_e2_classic.c
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+/* Efergy e2 classic (electricity meter)
+ *
+ * This electricity meter periodically reports current power consumption
+ * on frequency ~433.55 MHz. The data that is transmitted consists of 8
+ * bytes:
+ *
+ * Byte 1-4: Start bits (0000), then static data (probably device id)
+ * Byte 5-7: Current power consumption
+ * Byte 8: Checksum
+ *
+ * Power calculations come from Nathaniel Elijah's program EfergyRPI_001.
+ *
+ *
+ * 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.
+ */
+
+#include "rtl_433.h"
+
+static int efergy_e2_classic_callback(bitbuffer_t *bitbuffer) {
+	unsigned num_bits = bitbuffer->bits_per_row[0];
+	uint8_t *bytes = bitbuffer->bb[0];
+
+	if (num_bits < 64 || num_bits > 80) {
+		return 0;
+	}
+
+	// The bit buffer isn't always aligned to the transmitted data, so
+	// search for data start and shift out the bits which aren't part
+	// of the data. The data always starts with 0000 (or 1111 if
+	// gaps/pulses are mixed up).
+	while ((bytes[0] & 0xf0) != 0xf0 && (bytes[0] & 0xf0) != 0x00) {
+		num_bits -= 1;
+		if (num_bits < 64) {
+			return 0;
+		}
+
+		for (unsigned i = 0; i < (num_bits + 7) / 8; ++i) {
+			bytes[i] <<= 1;
+			bytes[i] |= (bytes[i + 1] & 0x80) >> 7;
+		}
+	}
+
+	// Sometimes pulses and gaps are mixed up. If this happens, invert
+	// all bytes to get correct interpretation.
+	if (bytes[0] & 0xf0) {
+		for (unsigned i = 0; i < 8; ++i) {
+			bytes[i] = ~bytes[i];
+		}
+	}
+
+	unsigned checksum = 0;
+	for (unsigned i = 0; i < 7; ++i) {
+		checksum += bytes[i];
+	}
+	checksum &= 0xff;
+	if (checksum != bytes[7]) {
+		return 0;
+	}
+
+	const unsigned VOLTAGES[] = {110, 115, 120, 220, 230, 240, 0};
+
+	double current_adc = 256 * bytes[4] + bytes[5];
+	for (unsigned i = 0; VOLTAGES[i] != 0; ++i) {
+		double power  = (VOLTAGES[i] * current_adc * (1 << bytes[6])) / 32768;
+		fprintf(stderr, "Power consumption at %u volts: %.2f watts\n", VOLTAGES[i], power);
+	}
+
+	return 1;
+}
+
+
+r_device efergy_e2_classic = {
+	.name           = "Efergy e2 classic",
+	.modulation     = FSK_PULSE_PWM_RAW,
+	.short_limit    = 92,
+	.long_limit     = 400,
+	.reset_limit    = 400,
+	.json_callback  = &efergy_e2_classic_callback,
+	.disabled       = 1,
+	.demod_arg      = 0,
+};