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

diff --git a/src/devices/danfoss.c b/src/devices/danfoss.c
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+++ b/src/devices/danfoss.c
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+/* Danfoss CFR Thermostat sensor protocol
+ *
+ * Manual: http://na.heating.danfoss.com/PCMPDF/Vi.88.R1.22%20CFR%20Thrm.pdf
+ *
+ * No protocol information found, so protocol is reverse engineered.
+ * Sensor uses FSK modulation and Pulse Code Modulated (direct bit sequence) data.
+ *
+ * Example received raw data package:
+ *   bitbuffer:: Number of rows: 1
+ *   [00] {255} 2a aa aa aa aa aa aa aa aa aa aa aa aa aa aa aa 36 5c a9 a6 93 6c 4d a6 a9 6a 6b 29 4f 19 72 b2
+ *
+ * The package starts with a long (~128 bit) synchronization preamble (0xaa).
+ * Sensor data consists of 21 nibbles of 4 bit, which are encoded with a 4b/6b encoder, resulting
+ * in an encoded sequence of 126 bits (~16 encoded bytes)
+ * The package may end with a noise bit or two.
+ *
+ * Example: <Received bits> | <6b/4b decoded nibbles>
+ *  365C A9A6 936C 4DA6 A96A 6B29 4F19 72B2 | E02 111E C4 6616 7C14 B02C
+ *
+ * Nibble content:
+ *  #0 -#2  -- Prefix - always 0xE02 (decoded)
+ *  #3 -#6  -- Sensor ID
+ *  #7      -- Message Count. Rolling counter incremented at each unique message.
+ *  #8      -- Switch setting -> 2="day", 4="timer", 8="night"
+ *  #9 -#10 -- Temperature decimal <value>/256
+ *  #11-#12 -- Temperature integer (in Celcius)
+ *  #13-#14 -- Set point decimal <value>/256
+ *  #15-#16 -- Set point integer (in Celcius)
+ *  #17-#20 -- CRC16, poly 0x1021, includes nibble #1-#16
+ *
+ * Copyright (C) 2016 Tommy Vestermark
+ * 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"
+#include "util.h"
+
+#define NUM_BYTES 10	// Output contains 21 nibbles, but skip first nibble 0xE, as it is not part of CRC and to get byte alignment
+static const uint8_t HEADER[] = { 0x36, 0x5c };	// Encoded prefix. Full prefix is 3 nibbles => 18 bits (but checking 16 is ok)
+static const uint16_t CRC_POLY = 0x1021;
+
+// Mapping from 6 bits to 4 bits
+static uint8_t danfoss_decode_nibble(uint8_t byte) {
+	uint8_t out = 0xFF;	// Error
+	switch(byte) {
+		case 0x0B:	out = 0xD;	break;
+		case 0x0D:	out = 0xE;	break;
+		case 0x0E:	out = 0x3;	break;
+		case 0x13:	out = 0x4;	break;
+		case 0x15:	out = 0xA;	break;
+		case 0x16:	out = 0xF;	break;
+		case 0x19:	out = 0x9;	break;
+		case 0x1A:	out = 0x6;	break;
+		case 0x25:	out = 0x0;	break;
+		case 0x26:	out = 0x7;	break;
+		case 0x29:	out = 0x1;	break;
+		case 0x2A:	out = 0x5;	break;
+		case 0x2C:	out = 0xC;	break;
+		case 0x31:	out = 0xB;	break;
+		case 0x32:	out = 0x2;	break;
+		case 0x34:	out = 0x8;	break;
+		default:	break;	// Error
+	}
+	return out;
+}
+
+
+static int danfoss_CFR_callback(bitbuffer_t *bitbuffer) {
+	uint8_t bytes[NUM_BYTES];	// Decoded bytes with two 4 bit nibbles in each
+	data_t *data;
+ 	char time_str[LOCAL_TIME_BUFLEN];
+
+	local_time_str(0, time_str);
+
+	// Validate package
+	unsigned bits = bitbuffer->bits_per_row[0];
+	if (bits >= 246 && bits <= 260) {	// Normal size is 255, but allow for some noise in preamble
+		// Find a package
+		unsigned bit_offset = bitbuffer_search(bitbuffer, 0, 112, HEADER, sizeof(HEADER)*8);	// Normal index is 128, skip first 14 bytes to find faster
+		if (bits-bit_offset < 126) {	// Package should be at least 126 bits
+			if (debug_output) {
+				fprintf(stderr, "Danfoss: short package. Header index: %u\n", bit_offset);
+				bitbuffer_print(bitbuffer);
+			}
+			return 0;
+		}
+		bit_offset += 6;	// Skip first nibble 0xE to get byte alignment and remove from CRC calculation
+
+		// Decode input 6 bit nibbles to output 4 bit nibbles (packed in bytes)
+		for (unsigned n=0; n<NUM_BYTES; ++n) {
+			uint8_t nibble_h = danfoss_decode_nibble(bitrow_get_byte(bitbuffer->bb[0], n*12+bit_offset) >> 2);
+			uint8_t nibble_l = danfoss_decode_nibble(bitrow_get_byte(bitbuffer->bb[0], n*12+bit_offset+6) >> 2);
+			if (nibble_h > 0xF || nibble_l > 0xF) {
+				if (debug_output) {
+					fprintf(stderr, "Danfoss: 6b/4b decoding error\n");
+					bitbuffer_print(bitbuffer);
+				}
+				return 0;
+			}
+			bytes[n] = (nibble_h << 4) | nibble_l;
+		}
+
+		// Output raw decoded data for debug
+		if (debug_output) {
+			char str_raw[NUM_BYTES*2+4];	// Add some extra space for line end
+			for (unsigned n=0; n<NUM_BYTES; ++n) {
+				sprintf(str_raw+n*2, "%02X", bytes[n]);
+			}
+			fprintf(stderr, "Danfoss: Raw 6b/4b decoded = %s\n", str_raw);
+		}
+
+		// Validate Prefix and CRC
+		uint16_t crc_calc = crc16_ccitt(bytes, NUM_BYTES-2, CRC_POLY, 0);
+		if (bytes[0] != 0x02		// Somewhat redundant to header search, but checks last bits
+		 || crc_calc != (((uint16_t)bytes[8] << 8) | bytes[9])
+		) {
+			if (debug_output) fprintf(stderr, "Danfoss: Prefix or CRC error.\n");
+			return 0;
+		}
+
+		// Decode data
+		unsigned id = (bytes[1] << 8) | bytes[2];
+
+		char *str_sw;
+		switch (bytes[3] & 0x0F) {
+			case 2:	 str_sw = "DAY"; break;
+			case 4:  str_sw = "TIMER"; break;
+			case 8:  str_sw = "NIGHT"; break;
+			default: str_sw = "ERROR";
+		}
+
+		float temp_meas  = (float)bytes[5] + (float)bytes[4] / 256.0;
+		float temp_setp  = (float)bytes[7] + (float)bytes[6] / 256.0;
+
+		// Output data
+		data = data_make(
+		     "time",		"",		DATA_STRING,	time_str,
+		     "model",		"",		DATA_STRING,	"Danfoss CFR Thermostat",
+		     "id",		"ID",		DATA_INT,	id,
+		     "temperature_C", 	"Temperature",	DATA_FORMAT,	"%.2f C", DATA_DOUBLE, temp_meas,
+		     "setpoint_C",	"Setpoint",	DATA_FORMAT,	"%.2f C", DATA_DOUBLE, temp_setp,
+		     "switch",		"Switch",	DATA_STRING,	str_sw,
+		     "crc", "", DATA_STRING, "ok",
+		     NULL);
+		data_acquired_handler(data);
+
+		return 1;
+	}
+	return 0;
+}
+
+
+static char *output_fields[] = {
+    "time",
+    "brand"
+    "model"
+    "id"
+    "temperature_C",
+    "setpoint_C",
+    "switch",
+    "crc",
+    NULL
+};
+
+r_device danfoss_CFR = {
+	.name           = "Danfoss CFR Thermostat",
+	.modulation     = FSK_PULSE_PCM,
+	.short_limit    = 100,	// NRZ decoding
+	.long_limit     = 100,	// Bit width
+	.reset_limit    = 500,	// Maximum run is 4 zeroes/ones
+	.json_callback  = &danfoss_CFR_callback,
+	.disabled       = 0,
+	.demod_arg      = 0,
+	.fields         = output_fields
+};