Add support for the Thermopro TP-12. This is based heavily on the code

for the Thermopro TP-11, and the modulation is compatible, but the bit
layout is fairly different and there are more sensors, so I've made this a
separate device.

AUTHORS

@@ -21,3 +21,4 @@ Helge Weissig <helgew@grajagan.org>
 Robert Fraczkiewicz <aromring@gmail.com>
 Nicola Quiriti <nik@wifi4all.it>
 Petr Konecny <pekon@google.com>
+Tom Felker <tomfelker@gmail.com>

include/rtl_433_devices.h

@@ -94,7 +94,8 @@
 		DECL(tpms_toyota) \
 		DECL(tpms_ford) \
 		DECL(tpms_renault) \
-		DECL(infactory)
+		DECL(infactory) \
+		DECL(thermopro_tp12)
 
 typedef struct {
 	char name[256];

src/CMakeLists.txt

@@ -103,6 +103,7 @@ add_executable(rtl_433
 	devices/tpms_ford.c
 	devices/tpms_renault.c
 	devices/infactory.c
+	devices/thermopro_tp12.c
 
 )
 

src/devices/thermopro_tp12.c

@@ -0,0 +1,143 @@
+/* Thermopro TP-12 Thermometer.
+ *
+ * Copyright (C) 2017 Google Inc.
+ * 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 "data.h"
+#include "rtl_433.h"
+#include "util.h"
+
+#define MODEL "Thermopro TP12 Thermometer"
+
+/*
+A normal sequence for the TP12:
+
+[00] {0} : 
+[01] {41} 38 73 21 bb 81 80 : 00111000 01110011 00100001 10111011 10000001 1
+[02] {41} 38 73 21 bb 81 80 : 00111000 01110011 00100001 10111011 10000001 1
+[03] {41} 38 73 21 bb 81 80 : 00111000 01110011 00100001 10111011 10000001 1
+[04] {41} 38 73 21 bb 81 80 : 00111000 01110011 00100001 10111011 10000001 1
+[05] {41} 38 73 21 bb 81 80 : 00111000 01110011 00100001 10111011 10000001 1
+[06] {41} 38 73 21 bb 81 80 : 00111000 01110011 00100001 10111011 10000001 1
+[07] {41} 38 73 21 bb 81 80 : 00111000 01110011 00100001 10111011 10000001 1
+[08] {41} 38 73 21 bb 81 80 : 00111000 01110011 00100001 10111011 10000001 1
+[09] {41} 38 73 21 bb 81 80 : 00111000 01110011 00100001 10111011 10000001 1
+[10] {41} 38 73 21 bb 81 80 : 00111000 01110011 00100001 10111011 10000001 1
+[11] {41} 38 73 21 bb 81 80 : 00111000 01110011 00100001 10111011 10000001 1
+[12] {41} 38 73 21 bb 81 80 : 00111000 01110011 00100001 10111011 10000001 1
+[13] {41} 38 73 21 bb 81 80 : 00111000 01110011 00100001 10111011 10000001 1
+[14] {41} 38 73 21 bb 81 80 : 00111000 01110011 00100001 10111011 10000001 1
+[15] {41} 38 73 21 bb 81 80 : 00111000 01110011 00100001 10111011 10000001 1
+[16] {41} 38 73 21 bb 81 80 : 00111000 01110011 00100001 10111011 10000001 1
+[17] {40} 38 73 21 bb 81 : 00111000 01110011 00100001 10111011 10000001 
+
+Layout appears to be:
+
+[01] {41} 38 73 21 bb 81 80 : 00111000 01110011 00100001 10111011 10000001 1
+                              device   temp 1   temp     temp 2   checksum
+                                       low bits 1   2    low bits
+                                                hi bits
+
+*/
+
+#define BITS_IN_VALID_ROW 40
+
+static int thermopro_tp12_sensor_callback(bitbuffer_t *bitbuffer) {
+    int iTemp1, iTemp2, good = -1;
+    float fTemp1, fTemp2;
+    bitrow_t *bb = bitbuffer->bb;
+    unsigned int device, value;
+    char time_str[LOCAL_TIME_BUFLEN];
+    data_t *data;
+
+    // The device transmits 16 rows, let's check for 3 matching.
+    // (Really 17 rows, but the last one doesn't match because it's missing a trailing 1.)
+    good = bitbuffer_find_repeated_row(bitbuffer, 3, 40);
+
+    if (good < 0) {
+        return 0;
+    }
+
+    // Note: the device ID changes randomly each time you replace the battery, so we can't early out based on it.
+    // This is probably to allow multiple devices to be used at once.  When you replace the receiver batteries
+    // or long-press its power button, it pairs with the first device ID it hears.
+    device = bb[good][0];
+
+    if(debug_output) {
+        // There is a mysterious checksum in bb[good][4].  It may be the same as the checksum used by the TP-11,
+        // which consisted of a lookup table containing, for each bit in the message, a byte to be xor-ed into
+        // the checksum if the message bit was 1.  It should be possible to solve for that table using Gaussian
+        // elimnation, so dump some data so we can try this.
+
+        // This format is easily usable by bruteforce-crc, after piping through | grep raw_data | cut -d':' -f2 
+        // bruteforce-crc didn't find anything, though - this may not be a CRC algorithm specifically.
+        fprintf(stderr,"thermopro_tp12_raw_data:");
+        for(int bit_index = 0; bit_index < 40; ++bit_index){
+            fputc(bitrow_get_bit(bb[good], bit_index) + '0', stderr);
+        }
+        fputc('\n', stderr);
+    }
+
+    iTemp1 = ((bb[good][2] & 0xf0) << 4) | bb[good][1];
+    iTemp2 = ((bb[good][2] & 0x0f) << 8) | bb[good][3];
+
+    fTemp1 = (iTemp1 - 200) / 10.;
+    fTemp2 = (iTemp2 - 200) / 10.;
+
+    local_time_str(0, time_str);
+    data = data_make("time",          "",            DATA_STRING, time_str,
+                     "model",         "",            DATA_STRING, MODEL,
+                     "id",            "Id",          DATA_FORMAT, "\t %d",   DATA_INT,    device,
+                     "temperature_1_C", "Temperature 1 (Food)", DATA_FORMAT, "%.01f C", DATA_DOUBLE, fTemp1,
+                     "temperature_2_C", "Temperature 2 (Barbecue)", DATA_FORMAT, "%.01f C", DATA_DOUBLE, fTemp2,
+                     NULL);
+    data_acquired_handler(data);
+    return 1;
+}
+
+static char *output_fields[] = {
+    "time",
+    "model",
+    "id",
+    "temperature_1_C",
+    "temperature_2_C",
+    NULL
+};
+
+/*
+Analyzing pulses...
+Total count:  714,  width: 273019		(1092.1 ms)
+Pulse width distribution:
+ [ 0] count:    1,  width:    26 [26;26]	( 104 us)
+ [ 1] count:  713,  width:   119 [116;140]	( 476 us)
+Gap width distribution:
+ [ 0] count:   17,  width:   895 [841;945]	(3580 us)
+ [ 1] count:  340,  width:   125 [123;128]	( 500 us)
+ [ 2] count:  340,  width:   369 [366;372]	(1476 us)
+ [ 3] count:   16,  width:   273 [272;274]	(1092 us)
+Pulse period distribution:
+ [ 0] count:   17,  width:  1027 [867;1084]	(4108 us)
+ [ 1] count:  340,  width:   244 [242;262]	( 976 us)
+ [ 2] count:  356,  width:   483 [390;490]	(1932 us)
+Level estimates [high, low]:  15891,     83
+Frequency offsets [F1, F2]:   18586,      0	(+70.9 kHz, +0.0 kHz)
+
+Those gaps are suspiciously close to 500 us and 1500 us.
+*/
+
+r_device thermopro_tp12 = {
+    .name          = MODEL,
+    .modulation    = OOK_PULSE_PPM_RAW,
+    // note that these are in microseconds, not samples.
+    .short_limit   = 1000,
+    .long_limit    = 2000,
+    .reset_limit   = 4000,
+    .json_callback = &thermopro_tp12_sensor_callback,
+    .disabled      = 0,
+    .demod_arg     = 0,
+    .fields        = output_fields,
+};