Add Support for RainPoint HCS012ARF Rain Gauge sensor

Author: ProfBoc75

include/rtl_433_devices.h

@@ -283,6 +283,7 @@
     DECL(gridstream384) \
     DECL(revolt_zx7717) \
     DECL(tpms_gm) \
+    DECL(rainpoint_hcs012arf) \
 
     /* Add new decoders here. */
 

src/CMakeLists.txt

@@ -204,6 +204,7 @@ add_library(r_433 STATIC
     devices/quinetic.c
     devices/radiohead_ask.c
     devices/rainpoint.c
+    devices/rainpoint_hcs012arf.c
     devices/regency_fan.c
     devices/revolt_nc5462.c
     devices/revolt_zx7717.c

src/devices/rainpoint_hcs012arf.c

@@ -0,0 +1,129 @@
+/** @file
+    RainPoint HCS012ARF Rain Gauge sensor.
+
+    Copyright (C) 2021 Christian W. Zuckschwerdt <zany@triq.net>
+    Copyright (C) 2025 Bruno OCTAU (ProfBoc75)
+
+    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"
+
+/**
+RainPoint HCS012ARF Rain Gauge sensor.
+
+Manufacturer:
+- Fujian Baldr Technology Co., Ltd
+
+RF Information:
+- Seen on 433.92 Mhz.
+- FCC ID : 2AWDBHCS008FRF
+- RF Module used in other RainPoint / Fujian Baldr Technology Co., Ltd devices : HCS008FRF, HCS012ARF, HTV113FRF, HTV213FRF, TTC819, TCS008B
+
+Description of the HCS012ARF Rain Gauge Sensor:
+- Rainfall Range: 0-9999mm , but 2 bytes identified, missing 1 bit MSB somewhere in the data layout flags
+- Accuracy: ±0.1mm
+- Data Reporting: Every 3 mins
+
+A Transmission contains ten packets with Manchester coded data, reflected
+
+Data layout:
+
+    Byte Index  0  1  2  3  4  5  6  7  8  9
+    Sample     a5 08 54 03 04 61 03 00 00 c7 [Batt inserted]
+               HH[II II II II FB FF RR RR]SS
+
+- HH: {8} Header, fixed 0xa5 (or 0xa4 when MC Zero bit decoded)
+- ID: {32} Sensor ID, does not change with new battery, looks unique
+- FF: {6} Fixed value, 0x18, may contains 1 bit MSB Rain Gauge
+- B:{1} Low Battery flag = 1, Good Battery = 0
+- B:{1} Powered on, batteries are inserted = 1, then always = 0
+- FF:{8} Fixed value, 0x03, may contains 1 bit MSB Rain Gauge
+- RR:{16} little-endian rain gauge value, scale 10 (1 Tip = 0,1 mm), 2 bytes are not enough, max 0xFFFF = 6553.5 mm, 1 bit MSB somewhere in flags ?
+- SS:{8} Byte sum of previous bytes except header [value in the hooks, from ID to Rain gauge].
+
+Raw data:
+
+    rtl_433 -X 'n=HCS012ARF,m=OOK_PCM,s=320,l=320,r=1000,g=700,repeats>=5,unique'
+
+
+*/
+
+static int rainpoint_hcs012arf_decode(r_device *decoder, bitbuffer_t *bitbuffer)
+{
+
+    // Find repeats
+    int row = bitbuffer_find_repeated_row(bitbuffer, 4, 163);
+    if (row < 0)
+        return DECODE_ABORT_EARLY;
+
+    if (bitbuffer->bits_per_row[row] > 163)
+        return DECODE_ABORT_LENGTH;
+
+    bitbuffer_t msg = {0};
+    bitbuffer_manchester_decode(bitbuffer, row, 0, &msg, 10 * 2 * 8); // including header
+    bitbuffer_invert(&msg);
+
+    uint8_t *b = msg.bb[0];
+    reflect_bytes(b, 10);
+
+    if (b[0] != 0xa5) // header = 0xa5, could be 0xa4 when MC Zero bit decoded
+        return DECODE_ABORT_EARLY;
+
+    decoder_log_bitrow(decoder, 2, __func__, b, 10 * 8, "MC and Reflect decoded");
+
+    // Checksum
+    int sum = add_bytes(&b[1], 8); // header not part of the sum
+    if ((sum & 0xff) != b[9]) {
+        decoder_logf(decoder, 2, __func__, "Checksum failed %04x vs %04x", b[9], sum);
+        return DECODE_FAIL_MIC;
+    }
+
+    int id       = (b[4] << 24) | (b[3] << 16) | (b[2] << 8) | b[1]; // just a guess, little-endian
+    int flags1   = b[5]; // may contains 1 bit MSB for Rain Gauge
+    int bat_low  = (flags1 & 0x02) >> 1;
+    //int bat_in   = (flags1 & 0x01); // power up, battery inserted = 1, then always 0
+    int flags2   = b[6];        // may contains 1 bit MSB for Rain Gauge
+    int rain_raw  = (b[8] << 8) | b[7]; // little-endian
+    float rain_mm = rain_raw * 0.1f;
+
+    /* clang-format off */
+    data_t *data = data_make(
+            "model",            "",                 DATA_STRING, "RainPoint-HCS012ARF",
+            "id",               "",                 DATA_INT,    id,     // decimal value reported at Rainpoint application
+            "flags1",           "Flags 1",          DATA_FORMAT, "%02x", DATA_INT,  (flags1 >> 2), // remove battery flags
+            "flags2",           "Flags 2",          DATA_FORMAT, "%02x", DATA_INT,  flags2,
+            "battery_ok",       "Battery",          DATA_INT,    !bat_low,
+            "rain_mm",          "Total rainfall",   DATA_FORMAT, "%.1f mm", DATA_DOUBLE, rain_mm,
+            "mic",              "Integrity",        DATA_STRING, "CHECKSUM",
+            NULL);
+    /* clang-format on */
+
+    decoder_output_data(decoder, data);
+    return 1;
+}
+
+static char const *const output_fields[] = {
+        "model",
+        "id",
+        "flags1",
+        "flags2",
+        "battery_ok",
+        "rain_mm",
+        "mic",
+        NULL,
+};
+
+r_device const rainpoint_hcs012arf = {
+        .name        = "RainPoint HCS012ARF Rain Gauge sensor",
+        .modulation  = OOK_PULSE_PCM,
+        .short_width = 320,
+        .long_width  = 320,
+        .reset_limit = 1000,
+        .gap_limit   = 700,
+        .decode_fn   = &rainpoint_hcs012arf_decode,
+        .fields      = output_fields,
+};