Add support for Arexx Multilogger (#2487)

README.md

@@ -349,6 +349,7 @@ See [CONTRIBUTING.md](./docs/CONTRIBUTING.md).
     [261]  Geevon TX16-3 outdoor sensor
     [262]  Fine Offset Electronics WH46 air quality sensor
     [263]  Vevor Wireless Weather Station 7-in-1
+    [264]  Arexx Multilogger IP-HA90, IP-TH78EXT, TSN-70E
 
 * Disabled by default, use -R n or a conf file to enable
 

conf/rtl_433.example.conf

@@ -490,6 +490,7 @@ convert si
   protocol 261 # Geevon TX16-3 outdoor sensor
   protocol 262 # Fine Offset Electronics WH46 air quality sensor
   protocol 263 # Vevor Wireless Weather Station 7-in-1
+  protocol 264 # Arexx Multilogger IP-HA90, IP-TH78EXT, TSN-70E
 
 ## Flex devices (command line option "-X")
 

include/rtl_433_devices.h

@@ -271,6 +271,7 @@
     DECL(geevon) \
     DECL(fineoffset_wh46) \
     DECL(vevor_7in1) \
+    DECL(arexx_ml) \
 
     /* Add new decoders here. */
 

src/CMakeLists.txt

@@ -54,6 +54,7 @@ add_library(r_433 STATIC
     devices/ant_antplus.c
     devices/arad_ms_meter.c
     devices/archos_tbh.c
+    devices/arexx_ml.c
     devices/atech_ws308.c
     devices/auriol_4ld5661.c
     devices/auriol_aft77b2.c

src/devices/arexx_ml.c

@@ -0,0 +1,155 @@
+/** @file
+    Arexx Multilogger.
+
+    Copyright (C) 2023 Christian W. Zuckschwerdt <[email protected]>
+    Protocol analysis by MacH-21, TSN-70E by inonoob.
+
+    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 "decoder.h"
+
+/**
+Arexx Multilogger.
+
+- Arexx IP-HA90 (MCP9808 sensor) s.a. #2388
+- Arexx IP-TH78EXT
+- Arexx TSN-70E (Sensirion SHT-10 sensor) s.a. #2482
+
+The IP-HA90 has a Microchip RFPIC12f675f at 433.92M and a Microchip MCP9808 temperature sensor.
+The TSN-70E has a Sensirion SHT-10 temperature and humidity and temperature sensor.
+
+FSK modulated with Manchester encoding, half-bit width is 208 us (2400bps MC).
+The sensors transmit approx. every 45 seconds alternating Temperature/Humidity.
+Polarity is inverted (IEEE MC) and the preamble+sync is aaaaaaaa55.
+
+Integrity check is done using CRC8 using poly=0x31 init=0x00.
+
+Example raw messages:
+
+    55555555aa f8 71fe fedf f777 5b a4  ff
+    55555555aa f8 71fe fedf f727 80 7f  ff
+    55555555aa f8 71fe fedf f6e7 8e 71  ff
+    55555555aa f8 71fe fedf f69f b4 4b  ff
+    55555555aa f8 71fe fedf f66f c0 3f  ff
+    55555555aa f8 71fe fedf f63f 1b e4  ff
+    55555555aa f8 71fe fedf f61f 38 c7  ff
+    55555555aa f8 71fe fedf f607 67 98  ff
+    55555555aa f8 71fe fedf f5f7 46 b9  ff
+    55555555aa f8 71fe fedf f5d7 65 9a  ff
+    55555555aa f8 71fe fedf f5b7 00 ff  ff
+    55555555aa f8 71fe fedf f59f e1 1e  ff
+    55555555aa fa 15b2 e90f 6c ff  faf7 7b1c e3
+    55555555aa fa 14b2 f90e 51 ff  faf7 7b1a e41
+    55555555aa fa 14b2 f991 01 ff  faf7 7b2a 401
+    55555555aa fa 15b2 e678 0f ff  faf7 7bf8 41
+
+Message format (preamble 5555aa then invert):
+
+    LEN:8h ID:<16h SENS:16h ?:8h8h CHK:8h CHKINV:8h 16x
+
+Message layout:
+
+    LL IIII SSSS UUUU XX YY
+
+- L : 8 bit: message length 7 or 5 (including length byte, excluding checksum)
+- I : 16 bit: ID, little-endian, even number = Temperature
+- S : 16 bit: raw sensor value
+- U : 16 bit: optional extra data, unknown
+- X : 8 bit: CRC, poly 0x31, init 0xc0
+- Y : 8 bit: inverted CRC check, only IP-HA90
+
+*/
+
+static int arexx_ml_decode(r_device *decoder, bitbuffer_t *bitbuffer)
+{
+    uint8_t const preamble[] = {0xaa, 0xaa, 0x55}; // 24 bits
+
+    if (bitbuffer->num_rows != 1) {
+        return DECODE_ABORT_EARLY; // we expect a single row
+    }
+    if (bitbuffer->bits_per_row[0] < 64 || bitbuffer->bits_per_row[1] > 130) {
+        return DECODE_ABORT_EARLY; // we expect around 88 to 104 bits
+    }
+    bitbuffer_invert(bitbuffer);
+
+    int msg_len = -1;
+    uint8_t b[9]; // allow up to 9 byte messages
+    for (int i = 0; i < bitbuffer->num_rows; ++i) {
+        unsigned pos = bitbuffer_search(bitbuffer, i, 0, preamble, 24);
+        pos += 24;
+
+        if (pos + 64 > bitbuffer->bits_per_row[i])
+            continue; // too short or not found
+
+        bitbuffer_extract_bytes(bitbuffer, i, pos, b, sizeof(b) * 8);
+        msg_len = b[0];
+        break;
+    }
+    if (msg_len <= 0) {
+        decoder_log(decoder, 2, __func__, "Couldn't find preamble");
+        return DECODE_FAIL_SANITY;
+    }
+
+    int chk = crc8le(b, msg_len, 0x31, 0x00);
+    if (chk != b[msg_len]) { // || (chk ^ b[msg_len + 1]) != 0) {
+        decoder_log(decoder, 2, __func__, "CRC fail");
+        return DECODE_FAIL_MIC;
+    }
+
+    // Extract data from buffer
+    int id       = (b[2] << 8) | (b[1]); // little-endian
+    int sens_val = (b[3] << 8) | (b[4]); // big-endian?
+    int is_humi  = id & 1; // even number: Temperature, odd number: Humidity
+
+    // MCP9808 Ambient Temperature Register "5-4":
+    int temp_alert = (sens_val >> 13) & 7;
+    int temp_raw   = (int16_t)(sens_val << 3); // uses sign-extend
+    float temp_c   = temp_raw / 128;
+
+    if (msg_len == 5) { // not sure if this is the proper check
+        // SHT10 Temperature
+        temp_c = sens_val * 0.01f - 40.0f; // offset actually varies by Vdd
+    }
+    // SHT10 Humidity
+    float humidity = -2.0468 + 0.0367 * sens_val - 1.5955E-6 * sens_val * sens_val;
+
+    /* clang-format off */
+    data_t *data = data_make(
+            "model",            "",                 DATA_STRING, "Arexx-ML",
+            "id",               "ID",               DATA_FORMAT, "%04x",    DATA_INT, id,
+            "temperature_C",    "Temperature",      DATA_COND, !is_humi,    DATA_FORMAT, "%.2f C", DATA_DOUBLE, temp_c,
+            "temperature_alert",  "Alert",          DATA_COND, !is_humi,    DATA_FORMAT, "%x", DATA_INT, temp_alert,
+            "humidity",         "Humidity",         DATA_COND, is_humi,     DATA_FORMAT, "%.1f %%", DATA_DOUBLE, humidity,
+            "sensor_raw",       "Sensor Raw",       DATA_FORMAT, "%04x",    DATA_INT, sens_val,
+            "mic",              "Integrity",        DATA_STRING, "CRC",
+            NULL);
+    /* clang-format on */
+
+    decoder_output_data(decoder, data);
+    return 1;
+}
+
+static char const *const arexx_ml_output_fields[] = {
+        "model",
+        "id",
+        "temperature_C",
+        "temperature_alert",
+        "humidity",
+        "sensor_raw",
+        "mic",
+        NULL,
+};
+
+r_device const arexx_ml = {
+        .name        = "Arexx Multilogger IP-HA90, IP-TH78EXT, TSN-70E",
+        .modulation  = FSK_PULSE_MANCHESTER_ZEROBIT,
+        .short_width = 208, // 2400bps MC
+        .long_width  = 208, // not used
+        .reset_limit = 450,
+        .decode_fn   = &arexx_ml_decode,
+        .fields      = arexx_ml_output_fields,
+};