--- /dev/null
+/* Template decoder
+ *
+ * Copyright © 2016 Benjamin Larsson
+ *
+ * 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.
+ */
+
+/* Use this as a starting point for a new decoder. */
+
+#include "rtl_433.h"
+#include "pulse_demod.h"
+#include "util.h"
+
+
+/*
+ * Hypothetical template device
+ *
+ * Message is 68 bits long
+ * Messages start with 0xAA
+ *
+ */
+#define MYDEVICE_BITLEN 68
+#define MYDEVICE_STARTBYTE 0xAA
+#define MYDEVICE_MSG_TYPE 0x10
+#define MYDEVICE_CRC_POLY 0x80
+#define MYDEVICE_CRC_INIT 0x00
+
+
+static int template_callback(bitbuffer_t *bitbuffer) {
+ char time_str[LOCAL_TIME_BUFLEN];
+ uint8_t *bb;
+ uint16_t brow, row_nbytes;
+ uint16_t sensor_id = 0;
+ uint8_t msg_type, r_crc, c_crc;
+ int16_t value;
+ data_t *data;
+ int valid = 0;
+
+
+ /*
+ * Early debugging aid to see demodulated bits in buffer and
+ * to determine if your limit settings are matched and firing
+ * this callback.
+ *
+ * 1. Enable with -D -D (debug level of 2)
+ * 2. Delete this block when your decoder is working
+ */
+ // if (debug_output > 1) {
+ // fprintf(stderr,"new_tmplate callback:\n");
+ // bitbuffer_print(bitbuffer);
+ // }
+
+ local_time_str(0, time_str);
+
+ /*
+ * bit buffer will contain multiple rows, many of them empty.
+ * Typically a complete message will be contained in a single
+ * row if long and reset limits are set correctly.
+ * May contain multiple message repeats.
+ * Message might not appear in row 0, if protocol uses
+ * start/preamble periods of different lengths.
+ */
+
+ for (brow = 0; brow < bitbuffer->num_rows; ++brow) {
+ bb = bitbuffer->bb[brow];
+
+ /*
+ * Validate message and reject invalid messages as
+ * early as possible before attempting to parse data..
+ *
+ * Check "message envelope"
+ * - valid message length
+ * - valid preamble/device type/fixed bits if any
+ * - Data integrity checks (CRC/Checksum/Parity)
+ */
+
+ if (bitbuffer->bits_per_row[brow] != 68)
+ continue;
+
+ /*
+ * number of bytes in row.
+ *
+ * Number of decoded bits may not be a multiple of 8.
+ * bitbuffer row will have enough bytes to contain
+ * all bytes, so round up.
+ */
+ row_nbytes = (bitbuffer->bits_per_row[brow] + 7)/8;
+
+
+ /*
+ * Reject rows that don't start with the correct start byte
+ * Example message should start with 0xAA
+ */
+ if (bb[0] != MYDEVICE_STARTBYTE)
+ continue;
+
+ /*
+ * Check message integrity (CRC/Checksum/parity)
+ *
+ * Example device uses CRC-8
+ */
+ r_crc = bb[row_nbytes - 1];
+ c_crc = crc8(bb, row_nbytes - 1, MYDEVICE_CRC_POLY, MYDEVICE_CRC_INIT);
+ if (r_crc != c_crc) {
+ // example debugging output
+ if (debug_output >= 1)
+ fprintf(stderr, "%s new_tamplate bad CRC: calculated %02x, received %02x\n",
+ time_str, c_crc, r_crc);
+
+ // reject row
+ continue;
+ }
+
+ /*
+ * Now that message "envelope" has been validated,
+ * start parsing data.
+ */
+
+ msg_type = bb[1];
+ sensor_id = bb[2] << 8 | bb[3];
+ value = bb[4] << 8 | bb[5];
+
+ if (msg_type != MYDEVICE_MSG_TYPE) {
+ /*
+ * received an unexpected message type
+ * could be a bad message or a new message not
+ * previously seen. Optionally log debug putput.
+ */
+ continue;
+ }
+
+ data = data_make("time", "", DATA_STRING, time_str,
+ "model", "", DATA_STRING, "New Template",
+ "id", "", DATA_INT, sensor_id,
+ "data","", DATA_INT, value,
+ NULL);
+
+ data_acquired_handler(data);
+
+ valid++;
+ }
+
+ // Return 1 if message successfully decoded
+ if (valid)
+ return 1;
+
+ return 0;
+}
+
+/*
+ * List of fields to output when using CSV
+ *
+ * Used to determine what fields will be output in what
+ * order for this devince when using -F csv.
+ *
+ */
+static char *csv_output_fields[] = {
+ "time",
+ "model",
+ "id",
+ "data",
+ NULL
+};
+
+/*
+ * r_device - registers device/callback. see rtl_433_devices.h
+ *
+ * Timings:
+ *
+ * short, long, nad reset - specify pulse/period timings
+ * based on number of samples at 250 Khz samples/second.
+ * These timings will determine if the received pulses
+ * match, so your callback will fire after demodulation.
+ *
+ * for readabiliy, specify timings based on 1 Mhz samples
+ * but a divide by 4 in the definition.
+ *
+ *
+ * Demodular:
+ *
+ * The function used to turn the received signal into bits.
+ * See:
+ * - pulse_demod.h for descriptions
+ * - rtL_433.h for the list of defined names
+ *
+ * This device is disabled by default. Enable it with -R 61 on the commandline
+ */
+
+r_device template = {
+ .name = "Template decoder",
+ .modulation = OOK_PULSE_PPM_RAW,
+ .short_limit = ((56+33)/2)*4,
+ .long_limit = (56+33)*4,
+ .reset_limit = (56+33)*2*4,
+ .json_callback = &template_callback,
+ .disabled = 1,
+ .demod_arg = 0,
+ .fields = csv_output_fields,
+};
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