Added initial bits for ST24 decoding

2026-06-08 02:17:07 +08:00 · 2014-07-10 13:14:39 +02:00
parent 58cae259e4
commit af4d5c0a3c
2 changed files with 206 additions and 0 deletions
@@ -0,0 +1,66 @@
+/****************************************************************************
+ *
+ *   Copyright (c) 2014 PX4 Development Team. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/*
+ * @file st24.h
+ *
+ * RC protocol implementation for Yuneec ST24 transmitter.
+ *
+ * @author Lorenz Meier <lm@inf.ethz.ch>
+ */
+
+uint8_t st24_common_crc8(uint8_t *ptr, uint8_t len)
+{
+	uint8_t i, crc ;
+	crc = 0;
+
+	while (len--) {
+		for (i = 0x80; i != 0; i >>= 1) {
+			if ((crc & 0x80) != 0) {
+				crc <<= 1;
+				crc ^= 0x07;
+
+			} else {
+				crc <<= 1;
+			}
+
+			if ((*ptr & i) != 0) {
+				crc ^= 0x07;
+			}
+		}
+
+		ptr++;
+	}
+
+	return (crc);
+}
@@ -0,0 +1,140 @@
+/****************************************************************************
+ *
+ *	Copyright (c) 2014 PX4 Development Team. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *	notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *	notice, this list of conditions and the following disclaimer in
+ *	the documentation and/or other materials provided with the
+ *	distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *	used to endorse or promote products derived from this software
+ *	without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/**
+ * @file st24.h
+ *
+ * RC protocol definition for Yuneec ST24 transmitter
+ *
+ * @author Lorenz Meier <lm@inf.ethz.ch>
+ */
+
+#define ST24_DATA_LEN_MAX	64
+
+enum {
+	ST24_PACKET_TYPE_CHANNELDATA12 = 0,
+	ST24_PACKET_TYPE_CHANNELDATA24,
+	ST24_PACKET_TYPE_TRANSMITTERGPSDATA
+} ST24_PACKET_TYPE;
+
+#pragma pack(push, 1)
+typedef struct {
+	uint8_t	header1;				///< 0x55 for a valid packet
+	uint8_t	header2;				///< 0x55 for a valid packet
+	uint8_t	length;				///< length includes type, data, and crc = sizeof(type)+sizeof(data[payload_len])+sizeof(crc8)
+	uint8_t	type;					///< from enum ST24_PACKET_TYPE
+	uint8_t	st24_data[ST24_DATA_LEN_MAX];
+	uint8_t	crc8;					///< crc8 checksum, calculated by st24_common_crc8 and including fields length, type and st24_data
+} ReceiverFcPacket;
+
+/**
+ * RC Channel data (12 channels).
+ *
+ * This is incoming from the ST24
+ */
+typedef struct {
+	uint16_t	t;						///< packet counter or clock
+	uint8_t	rssi					///< signal strength
+	uint8_t	packet_count;		///< Number of UART packets sent since reception of last RF frame (this tells something about age / rate)
+	uint8_t	channel[18];		///< channel data, 12 channels (12 bit numbers)
+} ChannelData12;
+
+/**
+ * RC Channel data (12 channels).
+ *
+ */
+typedef struct {
+	uint16_t	t;						///< packet counter or clock
+	uint8_t	rssi					///< signal strength
+	uint8_t	packet_count;		///< Number of UART packets sent since reception of last RF frame (this tells something about age / rate)
+	uint8_t	channel[36];		///< channel data, 24 channels (12 bit numbers)
+} ChannelData24;
+
+/**
+ * Telemetry packet
+ *
+ * This is outgoing to the ST24
+ *
+ * imuStatus:
+ * 8 bit total
+ * bits 0-2 for status
+ * - value 0 is FAILED
+ * - value 1 is INITIALIZING
+ * - value 2 is RUNNING
+ * - values 3 through 7 are reserved
+ * bits 3-7 are status for sensors (0 or 1)
+ * - mpu6050
+ * - accelerometer
+ * - primary gyro x
+ * - primary gyro y
+ * - primary gyro z
+ *
+ * pressCompassStatus
+ * 8 bit total
+ * bits 0-3 for compass status
+ * - value 0 is FAILED
+ * - value 1 is INITIALIZING
+ * - value 2 is RUNNING
+ * - value 3 - 15 are reserved
+ * bits 4-7 for pressure status
+ * - value 0 is FAILED
+ * - value 1 is INITIALIZING
+ * - value 2 is RUNNING
+ * - value 3 - 15 are reserved
+ *
+ */
+typedef struct {
+	uint16_t t;						///< packet counter or clock
+	int32_t	lat;					///< lattitude (degrees)	+/- 90 deg
+	int32_t	lon;					///< longitude (degrees)	+/- 180 deg
+	int32_t	alt;					///< 0.01m resolution, altitude (meters)
+	int16_t	vx, vy, vz; 		///< velocity 0.01m res, +/-320.00 North-East- Down
+	uint8_t	nsat;					///<number of satellites
+	uint8_t	voltage; 			///< 25.4V	voltage = 5 + 255*0.1 = 30.5V, min=5V
+	uint8_t	current; 			///< 0.5A resolution
+	int16_t	roll, pitch, yaw;	///< 0.01 degree resolution
+	uint8_t	motorStatus;		///< 1 bit per motor for status 1=good, 0= fail
+	uint8_t	imuStatus;			///< inertial measurement unit status
+	uint8_t	pressCompassStatus;	///< baro / compass status
+} TelemetryData;
+
+#pragma pack(pop)
+
+/**
+ * CRC8 implementation for ST24 protocol
+ *
+ * @param prt Pointer to the data to CRC
+ * @param len number of bytes to accumulate in the checksum
+ * @return the checksum of these bytes over len
+ */
+__EXPORT uint8_t st24_common_crc8(uint8_t *ptr, uint8_t len);