Add support for Rubicson pool thermometer 48942 (#2137)

README.md

@@ -304,6 +304,7 @@ See [CONTRIBUTING.md](./docs/CONTRIBUTING.md).
  [219] Fine Offset Electronics WH45 air quality sensor
  [220] Maverick XR-30 BBQ Sensor
  [221] Fine Offset Electronics WN34 temperature sensor
+ [222] Rubicson pool thermometer 48942
 
 * Disabled by default, use -R n or a conf file to enable
 

conf/rtl_433.example.conf

@@ -443,6 +443,7 @@ stop_after_successful_events false
  protocol 219 # Fine Offset Electronics WH45 air quality sensor
  protocol 220 # Maverick XR-30 BBQ Sensor
  protocol 221 # Fine Offset Electronics WN34 temperature sensor
+ protocol 222 # Rubicson pool thermometer 48942
 
 ## Flex devices (command line option "-X")
 

include/rtl_433_devices.h

@@ -229,6 +229,7 @@
  DECL(fineoffset_wh45) \
  DECL(maverick_xr30) \
  DECL(fineoffset_wn34) \
+ DECL(rubicson_pool_48942) \
 
  /* Add new decoders here. */
 

src/CMakeLists.txt

@@ -182,6 +182,7 @@ add_library(r_433 STATIC
  devices/rojaflex.c
  devices/rubicson.c
  devices/rubicson_48659.c
+ devices/rubicson_pool_48942.c
  devices/s3318p.c
  devices/schraeder.c
  devices/scmplus.c

src/devices/rubicson_pool_48942.c

@@ -0,0 +1,110 @@
+/** @file
+ Rubicson pool thermometer 48942 decoder.
+
+ Copyright (C) 2022 Robert Högberg
+
+ 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.
+*/
+
+/**
+Rubicson pool thermometer 48942 decoder.
+
+The device uses OOK and fixed period PWM.
+- 0 is encoded as 240 us pulse and 480 us gap,
+- 1 is encoded as 480 us pulse and 240 us gap.
+
+A transmission consists of an initial preamble followed by sync
+pulses and the data. Sync pulses and data are sent twice.
+
+Preamble:
+ __ ____ ____ ____ ____
+ | |____| |____| |____| |____| |__________
+ 480 980 980 980 980 980 980 980 980 3880 [us]
+
+Sync pulses:
+ ___ ___ ___ ___
+ | |___| |___| |___| |___
+ 730 730 730 730 730 730 730 730 [us]
+
+The device's transmission interval depends on the configured
+channel. The interval is 55 + <device channel> seconds.
+
+Data format:
+ 71 ba 4e 60 ba 0
+ 01110001 10111010 01001110 01100000 10111010 0
+ CCCCRRRR RRRRRR10 BTTTTTTT TTTT0000 XXXXXXXX 0
+
+- C: channel - offset by 1; 0000 means channel 1
+ The device can be configured to use channels 1-8
+- R: random power on id
+- 1: constant 1
+- 0: constant 0
+- B: low battery indicator
+- T: temperature - offset by 1024 and scaled by 10
+- X: CRC
+*/
+
+#include "decoder.h"
+
+static int rubicson_pool_48942_decode(r_device *decoder, bitbuffer_t *bitbuffer)
+{
+ int row = bitbuffer_find_repeated_row(bitbuffer, 2, 41);
+ if (row < 0 || bitbuffer->bits_per_row[row] != 41)
+ return DECODE_ABORT_LENGTH;
+
+ uint8_t *b = bitbuffer->bb[row];
+ bitbuffer_invert(bitbuffer);
+
+ // validate some static bits
+ if (b[3] & 0xF || b[5])
+ return DECODE_ABORT_EARLY;
+
+ if (crc8(b, 4, 0x31, 0x00) != b[4])
+ return DECODE_FAIL_MIC;
+
+ int channel = (b[0] >> 4) + 1;
+ int random_id = (b[0] & 0x0F) << 6 | (b[1] & 0xFC) >> 2;
+ int battery_low = b[2] >> 7;
+ float temp_c = ((((b[2] & 0x7F) << 4) | (b[3] >> 4)) - 1024) * 0.1f;
+
+ decoder_log_bitbuffer(decoder, 1, __func__, bitbuffer, "");
+
+ /* clang-format off */
+ data_t *data = data_make(
+ "model", "", DATA_STRING, "Rubicson-48942",
+ "channel", "Channel", DATA_INT, channel,
+ "id", "Random ID", DATA_INT, random_id,
+ "battery_ok", "Battery", DATA_INT, !battery_low,
+ "temperature_C", "Temperature", DATA_FORMAT, "%.1f C", DATA_DOUBLE, temp_c,
+ "mic", "Integrity", DATA_STRING, "CRC",
+ NULL);
+ /* clang-format on */
+
+ decoder_output_data(decoder, data);
+ return 1;
+}
+
+static char *output_fields[] = {
+ "model",
+ "channel",
+ "id",
+ "battery_ok",
+ "temperature_C",
+ "mic",
+ NULL,
+};
+
+r_device rubicson_pool_48942 = {
+ .name = "Rubicson Pool Thermometer 48942",
+ .modulation = OOK_PULSE_PWM,
+ .short_width = 280,
+ .long_width = 480,
+ .reset_limit = 6000,
+ .gap_limit = 5000,
+ .sync_width = 730,
+ .decode_fn = &rubicson_pool_48942_decode,
+ .fields = output_fields,
+};