X-Git-Url: https://git.rvb.name/rtl-433.git/blobdiff_plain/ca13278b24eb61443559bcb61e64627fba3d8823..6d15c6f967221af825cf84e3ed12b96c763b127b:/src/devices/steelmate.c

diff --git a/src/devices/steelmate.c b/src/devices/steelmate.c
new file mode 100644
index 0000000..9086734
--- /dev/null
+++ b/src/devices/steelmate.c
@@ -0,0 +1,127 @@
+/* Steelmate TPMS FSK protocol
+ *
+ * Copyright © 2016 Benjamin Larsson
+ * Copyright © 2016 John Jore
+ *
+ * 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.
+ *
+ * Packet payload: 9 bytes.
+ * Bytes 2 to 9 are inverted Manchester with swaped MSB/LSB:
+ *
+ *                               0  1  2  3  4  5  6  7  8
+ *                    [00] {72} 00 00 7f 3c f0 d7 ad 8e fa
+ * After translating            00 00 01 c3 f0 14 4a 8e a0
+ *                              SS SS AA II II PP TT BB CC
+ * S = sync, (0x00)
+ * A = preamble, (0x01)
+ * I = id, 0xc3f0
+ * P = Pressure as double the PSI, 0x14 = 10 PSI
+ * T = Temperature in Fahrenheit, 0x4a = 74 'F
+ * B = Battery as half the millivolt, 0x8e = 2.84 V
+ * C = Checksum, adding bytes 2 to 7 modulo 256 = byte 8,(0x01+0xc3+0xf0+0x14+0x4a+0x8e) modulus 256 = 0xa0
+ */
+
+
+#include "rtl_433.h"
+#include "pulse_demod.h"
+#include "util.h"
+
+static int steelmate_callback(bitbuffer_t *bitbuffer) {
+	//if (debug_output >= 1) {
+	//	fprintf(stdout, "Steelmate TPMS decoder\n");
+	//	bitbuffer_print(bitbuffer);
+	//	fprintf(stdout, "\n");
+	//}
+
+	char time_str[LOCAL_TIME_BUFLEN];
+	local_time_str(0, time_str);
+	bitrow_t *bb = bitbuffer->bb;
+
+	//Loop through each row of data
+	for (int i = 0; i < bitbuffer->num_rows; i++)
+	{
+		//Payload is inverted Manchester encoded, and reversed MSB/LSB order
+		uint8_t preAmble, ID1, ID2, p1, tempFahrenheit, tmpbattery_mV, payload_checksum, calculated_checksum;
+		uint16_t sensorID, battery_mV;
+		float pressurePSI;
+		char sensorIDhex[7];
+		data_t *data;
+
+		//Length must be 72 bits to be considered a valid packet
+		if (bitbuffer->bits_per_row[i] != 72)
+			continue;
+
+		//Valid preamble? (Note, the data is still wrong order at this point. Correct pre-amble: 0x00 0x00 0x01)
+		if (bb[i][0] != 0x00 || bb[i][1] != 0x00 || bb[i][2] != 0x7f)
+			continue;
+
+		//Preamble
+		preAmble = ~reverse8(bb[i][2]);
+
+		//Sensor ID
+		ID1 = ~reverse8(bb[i][3]);
+		ID2 = ~reverse8(bb[i][4]);
+
+		//Pressure is stored as twice the PSI
+		p1 = ~reverse8(bb[i][5]);
+
+		//Temperature is stored in Fahrenheit. Note that the datasheet claims operational to -40'C, but can only express values from -17.8'C
+		tempFahrenheit = ~reverse8(bb[i][6]);
+
+		//Battery voltage is stored as half the mV
+		tmpbattery_mV = ~reverse8(bb[i][7]);
+
+		//Checksum is a sum of all the other values
+		payload_checksum = ~reverse8(bb[i][8]);
+		calculated_checksum = preAmble + ID1 + ID2 + p1 + tempFahrenheit + tmpbattery_mV;
+		if (payload_checksum != calculated_checksum)
+			continue;
+
+		sensorID = (ID1 << 8) + ID2;
+		sprintf(sensorIDhex, "0x%04x", sensorID);
+		pressurePSI = (float)p1 / 2;
+		battery_mV = tmpbattery_mV * 2;
+
+		data = data_make("time", "", DATA_STRING, time_str,
+			"type", "", DATA_STRING, "TPMS",
+			"make", "", DATA_STRING, "Steelmate",
+			"id", "", DATA_STRING, sensorIDhex,
+			"pressure_PSI", "", DATA_DOUBLE, pressurePSI,
+			"temperature_F", "", DATA_DOUBLE, (float)tempFahrenheit,
+			"battery_mV", "", DATA_INT, battery_mV,
+			"checksum", "", DATA_STRING, "OK",
+			NULL);
+		data_acquired_handler(data);
+
+		return 1;
+	}
+
+	//Was not a Steelmate TPMS after all
+	return 0;
+}
+
+static char *output_fields[] = {
+	"time",
+	"type",
+	"make",
+	"id",
+	"pressure_PSI",
+	"temperature_F",
+	"battery_mV",
+	"checksum",
+	NULL
+};
+
+r_device steelmate = {
+	.name			= "Steelmate TPMS",
+	.modulation		= FSK_PULSE_MANCHESTER_ZEROBIT,
+	.short_limit	= 12*4,
+	.long_limit     = 0,
+	.reset_limit    = 27*4,
+	.json_callback	= &steelmate_callback,
+	.disabled		= 0,
+	.fields			= output_fields,
+};