Add support for Celsia CZC1 (merbanan#2391)

Co-authored-by: Liban Hannan <liban.p@gmail.com>
bitfliq · Mar 5, 2023 · c949e07 · c949e07
1 parent fd66298
commit c949e07
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diff --git a/include/rtl_433_devices.h b/include/rtl_433_devices.h
@@ -250,6 +250,7 @@
     DECL(lacrosse_tx31u) \
     DECL(tpms_eezrv) \
     DECL(baldr_rain) \
+    DECL(celsia_czc1) \
 
     /* Add new decoders here. */
 

diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
@@ -75,6 +75,7 @@ add_library(r_433 STATIC
     devices/cardin.c
     devices/cavius.c
     devices/ced7000.c
+    devices/celsia_czc1.c
     devices/chuango.c
     devices/cmr113.c
     devices/companion_wtr001.c

diff --git a/src/devices/celsia_czc1.c b/src/devices/celsia_czc1.c
@@ -0,0 +1,166 @@
+/** @file
+    Celsia CZC1 Thermostat.
+
+    Copyright (C) 2023 Liban Hannan <liban.p@gmail.com>
+
+    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 celsia_czc1_decode(r_device *decoder, bitbuffer_t *bitbuffer)
+Celsia CZC1 Thermostat.
+
+A PID thermostat compatible with various manufacturers' heaters.
+
+demod: OOK_PCM
+short: 1220
+long: 1220
+reset: 4880
+
+A packet starts with a preamble of {40}cccccccccccccccccccc, followed by a sync
+of {32}55555555 signalling the start of the data symbols. The packet is
+terminated with {8}f0.  Each symbol is 4 'raw' bits long: 0101(5) = 0, 1010(a)
+= 1. Command packets have 5 bytes of data, pairing packets have 4.
+
+```
+rtl_433 -X n=CZC1,m=OOK_PCM,s=1220,l=1220,r=4880,preamble=cccccccc55555555
+```
+
+Data layout:
+
+Command packet (5 bytes)
+
+- ID:   {16} ID
+- Type: {8}  type
+- Heat: {8}  heating level 0-255 (little endian unsigned integer)
+- CRC:  {8}  CRC-8, poly 0x31, init 0xd7
+
+Pairing packet (4 bytes)
+
+- ID:   {16} ID
+- Type: {8}  type
+- CRC:  {8}  CRC-8, poly 0x31, init 0xd7
+
+*/
+
+static int celsia_czc1_decode(r_device *decoder, bitbuffer_t *bitbuffer)
+{
+
+    uint8_t const preamble[] = {0xcc, 0xcc, 0xcc, 0xcc, 0x55, 0x55, 0x55, 0x55};
+    // data section in command packet == 160 bits
+    // data section in pair packet == 128 bits
+    // terminal 0xf == 4 bits
+
+    if (bitbuffer->num_rows > 1 || bitbuffer->bits_per_row[0] < 144) {
+        return DECODE_ABORT_EARLY;
+    }
+
+    unsigned preamble_end = bitbuffer_search(bitbuffer, 0, 0, preamble, 64) + 64;
+    unsigned first_byte = preamble_end >> 3;
+
+    if (preamble_end >= bitbuffer->bits_per_row[0]) {
+        return DECODE_ABORT_EARLY;
+    }
+
+    if ((preamble_end + 132) > bitbuffer->bits_per_row[0]) {
+        return DECODE_ABORT_LENGTH;
+    }
+
+    bitbuffer_t decoded_bits = {0};
+    //convert raw bits to symbols
+
+    uint8_t *bits = bitbuffer->bb[0];
+    unsigned int n_bytes = bitbuffer->bits_per_row[0] >> 3;
+    unsigned int ipos = first_byte;
+    while (ipos < n_bytes) {
+        if (bits[ipos] == 0xf0) {
+            break;
+        }
+        switch (bits[ipos]) {
+            case 0x55:
+                bitbuffer_add_bit(&decoded_bits, 0);
+                bitbuffer_add_bit(&decoded_bits, 0);
+                break;
+            case 0x5a:
+                bitbuffer_add_bit(&decoded_bits, 0);
+                bitbuffer_add_bit(&decoded_bits, 1);
+                break;
+            case 0xa5:
+                bitbuffer_add_bit(&decoded_bits, 1);
+                bitbuffer_add_bit(&decoded_bits, 0);
+                break;
+            case 0xaa:
+                bitbuffer_add_bit(&decoded_bits, 1);
+                bitbuffer_add_bit(&decoded_bits, 1);
+                break;
+        }
+        ipos++;
+    }
+
+
+    decoder_log_bitbuffer(decoder, 2, __func__, &decoded_bits, "Extracted data") ;
+    uint8_t *b = decoded_bits.bb[0];
+
+    uint8_t crc = crc8(b, 8, 0x31, 0xd7);
+    if (crc != 0) {
+        decoder_log(decoder, 2, __func__,"Decode failed: CRC failed");
+        return DECODE_FAIL_MIC;
+    }
+    int id = (b[0] << 8) | b[1];
+
+    data_t *data;
+    if (b[2] == 0x00) { // pair packet
+        /* clang-format off */
+        data = data_make(
+            "model",    "",               DATA_STRING, "Celsia-CZC1",
+            "id",       "ID",             DATA_FORMAT, "%x", DATA_INT, id,
+            "mic",      "Integrity",      DATA_STRING, "CRC",
+            NULL);
+        /* clang-format on */
+    } else if (b[2] == 0xf0) { // command packet
+        int heat = reverse8(b[3]);
+        if (heat < 0 || 255 < heat) {
+           return DECODE_FAIL_OTHER;
+        }
+
+        /* clang-format off */
+        data = data_make(
+            "model",    "",               DATA_STRING, "Celsia-CZC1",
+            "id",       "ID",             DATA_FORMAT, "%x", DATA_INT, id,
+            "heat",     "Heat",           DATA_INT,    heat,
+            "mic",      "Integrity",      DATA_STRING, "CRC",
+            NULL);
+        /* clang-format on */
+    } else {
+        return DECODE_FAIL_OTHER;
+    }
+
+    decoder_output_data(decoder, data);
+    return 1;
+}
+
+static char const *output_fields[] = {
+        "model",
+        "id",
+        "type",
+        "heat",
+        "mic",
+        NULL,
+};
+
+//rtl_433 -X n=CZC1,m=OOK_PCM,s=1220,l=1220,r=4880,preamble=cccccccc55555555
+
+r_device const celsia_czc1= {
+        .name        = "Celsia CZC1 Thermostat",
+        .modulation  = OOK_PULSE_PCM,
+        .short_width = 1220,   // each pulse is ~1220 us (nominal bit width)
+        .long_width  = 1220,   // each pulse is ~1220 us (nominal bit width)
+        .reset_limit = 4880, // larger than gap between start pulse and first frame (6644 us = 11 x nominal bit width) to put start pulse and first frame in two rows, but smaller than inter-frame space of 30415 us
+        .tolerance   = 20,
+        .decode_fn   = &celsia_czc1_decode,
+        .fields      = output_fields,
+};