From e2f5c8e4985c44439ca5a6640456dfadc0866c5a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=C3=85dne=20Hovda?= <aadne@hovda.no>
Date: Fri, 1 Mar 2024 12:12:51 +0100
Subject: [PATCH] Add support for Watts WFHT-RF thermostat (#2648)
---
README.md | 1 +
conf/rtl_433.example.conf | 1 +
include/rtl_433_devices.h | 1 +
src/CMakeLists.txt | 1 +
src/devices/watts_thermostat.c | 190 +++++++++++++++++++++++++++++++++
5 files changed, 194 insertions(+)
create mode 100644 src/devices/watts_thermostat.c
diff --git a/README.md b/README.md
index 89665dfc..802bb22b 100644
--- a/README.md
+++ b/README.md
@@ -338,6 +338,7 @@ See [CONTRIBUTING.md](./docs/CONTRIBUTING.md).
[250] Schou 72543 Day Rain Gauge, Motonet MTX Rain, MarQuant Rain Gauge
[251] Fine Offset / Ecowitt WH55 water leak sensor
[252] BMW Gen5 TPMS, multi-brand HUF, Continental, Schrader/Sensata
+ [253] Watts WFHT-RF Thermostat
* Disabled by default, use -R n or a conf file to enable
diff --git a/conf/rtl_433.example.conf b/conf/rtl_433.example.conf
index 0461bea2..7ef082f0 100644
--- a/conf/rtl_433.example.conf
+++ b/conf/rtl_433.example.conf
@@ -479,6 +479,7 @@ convert si
protocol 250 # Schou 72543 Day Rain Gauge, Motonet MTX Rain, MarQuant Rain Gauge
protocol 251 # Fine Offset / Ecowitt WH55 water leak sensor
protocol 252 # BMW Gen5 TPMS, multi-brand HUF, Continental, Schrader/Sensata
+ protocol 253 # Watts WFHT-RF Thermostat
## Flex devices (command line option "-X")
diff --git a/include/rtl_433_devices.h b/include/rtl_433_devices.h
index abb5157a..80419954 100644
--- a/include/rtl_433_devices.h
+++ b/include/rtl_433_devices.h
@@ -260,6 +260,7 @@
DECL(schou_72543_rain) \
DECL(fineoffset_wh55) \
DECL(tpms_bmw) \
+ DECL(watts_thermostat) \
/* Add new decoders here. */
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 5fed8604..d7e81d5a 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -254,6 +254,7 @@ add_library(r_433 STATIC
devices/vaillant_vrt340f.c
devices/vauno_en8822c.c
devices/visonic_powercode.c
+ devices/watts_thermostat.c
devices/waveman.c
devices/wec2103.c
devices/wg_pb12v1.c
diff --git a/src/devices/watts_thermostat.c b/src/devices/watts_thermostat.c
new file mode 100644
index 00000000..02283561
--- /dev/null
+++ b/src/devices/watts_thermostat.c
@@ -0,0 +1,190 @@
+/** @file
+ Watts WFHT-RF Thermostat.
+
+ Copyright (C) 2022 Ådne Hovda <aadne@hovda.no>
+ based on protocol decoding by Christian W. Zuckschwerdt <zany@triq.net>
+ and Ådne Hovda <aadne@hovda.no>
+
+ 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"
+
+/** @fn int watts_thermostat_decode(r_device *decoder, bitbuffer_t *bitbuffer)
+Watts WFHT-RF Thermostat.
+
+This code is based on a slightly older OEM system created by ADEV in France which
+later merged with Watts. The closest thing currently available seems to be
+https://wattswater.eu/catalog/regulation-and-control/radio-wfht-thermostats/electronic-room-thermostat-with-rf-control-wfht-rf-basic/,
+but it is not known whether they are protocol compatible.
+
+Modulation is PWM with preceeding gap. There is a very long lead-in pulse.
+Symbols are ~260 us gap + ~600 us pulse and ~600 us gap + ~260 us pulse.
+Bits are inverted and reflected.
+
+Example Data:
+
+ 10100101 1011010001110110 1000 100100001 000011000 10101011
+ preamble id flags temp setpoint chksum
+
+Data Layout:
+
+ PP II II F .TT .SS XX
+
+- P: (8-bit reflected) Preamble
+- I: (16-bit reflected) ID
+- F: (4-bit reflected) Flags
+- T: (9-bit reflected) Temperature
+- S: (9-bit reflected) Set-Point
+- X: (8-bit reflected) Checksum (8-bit sum)
+
+ The only flag found is PAIRING (0b0001). Chksum is calculated by summing all
+ high and low bytes the for ID, Flags, Temperature and Set-Point.
+
+ Temperature and Set-Point values are in 0.1°C steps with an observed Set-Point
+ range of ~4°C to ~30°C.
+
+Raw data:
+
+ {54}5ab24971f79994
+ {54}5ab24971f79994
+ {54}5ab249f1f79b94
+ {54}5ab249f1f79b94
+ {54}5ab249f9f79854
+ {54}5ab249f5f79a54
+ {54}5ab249f68f998c
+ {54}5ab249f98f9a4c
+ {54}5ab249f58b9a4c
+ {54}5ab249fb8f9acc
+
+ https://tinyurl.com/wattsthermobitbench
+
+ Format string:
+ PRE:^8h ID:^16d FLAGS:^4b TEMP:^9d SETP:^9d CHK:^8d
+
+Decoded example:
+
+ PRE:a5 ID:28082 FLAGS:0001 TEMP:271 SETP:304 CHK:097
+ PRE:a5 ID:28252 FLAGS:0000 TEMP:019 SETP:303 CHK:013
+
+*/
+
+#define WATTSTHERMO_BITLEN 54
+#define WATTSTHERMO_PREAMBLE_BITLEN 8
+#define WATTSTHERMO_ID_BITLEN 16
+#define WATTSTHERMO_FLAGS_BITLEN 4
+#define WATTSTHERMO_TEMPERATURE_BITLEN 9
+#define WATTSTHERMO_SETPOINT_BITLEN 9
+#define WATTSTHERMO_CHKSUM_BITLEN 8
+
+enum WATTSTHERMO_FLAGS {
+ WF_NONE = 0,
+ WF_PAIRING = 1,
+ WF_UNKNOWN1 = 2,
+ WF_UNKNOWN2 = 4,
+ WF_UNKNOWN3 = 8,
+};
+
+static int watts_thermostat_decode(r_device *decoder, bitbuffer_t *bitbuffer)
+{
+ uint8_t const preamble_pattern[] = {0xa5}; // inverted and reflected, raw value is 0x5a
+
+ bitbuffer_invert(bitbuffer);
+
+ // We're expecting a single row
+ for (uint16_t row = 0; row < bitbuffer->num_rows; ++row) {
+
+ uint16_t row_len = bitbuffer->bits_per_row[row];
+ unsigned bitpos = 0;
+
+ bitpos = bitbuffer_search(bitbuffer, row, 0, preamble_pattern, WATTSTHERMO_PREAMBLE_BITLEN);
+ if (bitpos >= row_len) {
+ decoder_log(decoder, 2, __func__, "Preamble not found");
+ return DECODE_ABORT_EARLY;
+ }
+
+ if (row_len < WATTSTHERMO_BITLEN) {
+ decoder_log(decoder, 2, __func__, "Message too short");
+ return DECODE_ABORT_LENGTH;
+ }
+ bitpos += WATTSTHERMO_PREAMBLE_BITLEN;
+
+ uint8_t id_raw[2];
+ bitbuffer_extract_bytes(bitbuffer, row, bitpos, id_raw, WATTSTHERMO_ID_BITLEN);
+ reflect_bytes(id_raw, 2);
+ int id = (id_raw[1] << 8) | id_raw[0];
+ bitpos += WATTSTHERMO_ID_BITLEN;
+
+ uint8_t flags[1];
+ bitbuffer_extract_bytes(bitbuffer, row, bitpos, flags, WATTSTHERMO_FLAGS_BITLEN);
+ reflect_bytes(flags, 1);
+ int pairing = flags[0] & WF_PAIRING;
+ bitpos += WATTSTHERMO_FLAGS_BITLEN;
+
+ uint8_t temp_raw[2];
+ bitbuffer_extract_bytes(bitbuffer, row, bitpos, temp_raw, WATTSTHERMO_TEMPERATURE_BITLEN);
+ reflect_bytes(temp_raw, 2);
+ int temp = (temp_raw[1] << 8) | temp_raw[0];
+ bitpos += WATTSTHERMO_TEMPERATURE_BITLEN;
+
+ uint8_t setp_raw[2];
+ bitbuffer_extract_bytes(bitbuffer, row, bitpos, setp_raw, WATTSTHERMO_SETPOINT_BITLEN);
+ reflect_bytes(setp_raw, 2);
+ int setp = (setp_raw[1] << 8) | setp_raw[0];
+ bitpos += WATTSTHERMO_SETPOINT_BITLEN;
+
+ uint8_t chksum = add_bytes(id_raw, 2)
+ + add_bytes(flags, 1)
+ + add_bytes(temp_raw, 2)
+ + add_bytes(setp_raw, 2);
+
+ uint8_t chk[1];
+ bitbuffer_extract_bytes(bitbuffer, row, bitpos, chk, WATTSTHERMO_CHKSUM_BITLEN);
+ reflect_bytes(chk, 1);
+ if (chk[0] != chksum) {
+ decoder_log_bitbuffer(decoder, 1, __func__, bitbuffer, "Checksum fail");
+ return DECODE_FAIL_MIC;
+ }
+
+ /* clang-format off */
+ data_t *data = data_make(
+ "model", "Model", DATA_STRING, "Watts-WFHTRF",
+ "id", "ID", DATA_INT, id,
+ "pairing", "Pairing", DATA_INT, pairing,
+ "temperature_C", "Temperature", DATA_FORMAT, "%.1f C", DATA_DOUBLE, temp * 0.1f,
+ "setpoint_C", "Setpoint", DATA_FORMAT, "%.1f C", DATA_DOUBLE, setp * 0.1f,
+ "flags", "Flags", DATA_INT, flags[0],
+ "mic", "Integrity", DATA_STRING, "CHECKSUM",
+ NULL);
+ /* clang-format on */
+
+ decoder_output_data(decoder, data);
+ return 1;
+ }
+ return 0;
+}
+
+static char const *const output_fields[] = {
+ "model",
+ "id",
+ "pairing",
+ "temperature_C",
+ "setpoint_C",
+ "flags",
+ "mic",
+ NULL,
+};
+
+r_device const watts_thermostat = {
+ .name = "Watts WFHT-RF Thermostat",
+ .modulation = OOK_PULSE_PWM,
+ .short_width = 260,
+ .long_width = 600,
+ .sync_width = 6000,
+ .reset_limit = 900,
+ .decode_fn = &watts_thermostat_decode,
+ .fields = output_fields,
+};