ardupilot/libraries/AP_ADSB/AP_ADSB_Sagetech.cpp

554 lines
20 KiB
C++

/*
Copyright (C) 2020 Kraus Hamdani Aerospace Inc. All rights reserved.
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 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include "AP_ADSB_Sagetech.h"
#if HAL_ADSB_SAGETECH_ENABLED
#include <GCS_MAVLink/GCS.h>
#include <AP_AHRS/AP_AHRS.h>
#include <AP_RTC/AP_RTC.h>
#include <AP_HAL/utility/sparse-endian.h>
#include <stdio.h>
#include <time.h>
#include <string.h>
#include <math.h>
#define SAGETECH_SCALER_LATLNG (1.0f/2.145767E-5f) // 180/(2^23)
#define SAGETECH_SCALER_KNOTS_TO_CMS ((KNOTS_TO_M_PER_SEC/0.125f) * 100.0f)
#define SAGETECH_SCALER_ALTITUDE (1.0f/0.015625f)
#define SAGETECH_SCALER_HEADING_CM ((360.0f/256.0f) * 100.0f)
#define SAGETECH_VALIDFLAG_LATLNG (1U<<0)
#define SAGETECH_VALIDFLAG_ALTITUDE (1U<<1)
#define SAGETECH_VALIDFLAG_VELOCITY (1U<<2)
#define SAGETECH_VALIDFLAG_GND_SPEED (1U<<3)
#define SAGETECH_VALIDFLAG_HEADING (1U<<4)
#define SAGETECH_VALIDFLAG_V_RATE_GEO (1U<<5)
#define SAGETECH_VALIDFLAG_V_RATE_BARO (1U<<6)
#define SAGETECH_VALIDFLAG_EST_LATLNG (1U<<7)
#define SAGETECH_VALIDFLAG_EST_VELOCITY (1U<<8)
// detect if any port is configured as Sagetech
bool AP_ADSB_Sagetech::detect()
{
return (AP::serialmanager().find_serial(AP_SerialManager::SerialProtocol_ADSB, 0) != nullptr);
}
// Init, called once after class is constructed
bool AP_ADSB_Sagetech::init()
{
_port = AP::serialmanager().find_serial(AP_SerialManager::SerialProtocol_ADSB, 0);
return (_port != nullptr);
}
void AP_ADSB_Sagetech::update()
{
if (_port == nullptr) {
return;
}
const uint32_t now_ms = AP_HAL::millis();
// -----------------------------
// read any available data on serial port
// -----------------------------
uint32_t nbytes = MIN(_port->available(), 10 * PAYLOAD_XP_MAX_SIZE);
while (nbytes-- > 0) {
const int16_t data = (uint8_t)_port->read();
if (data < 0) {
break;
}
if (parse_byte_XP((uint8_t)data)) {
handle_packet_XP(message_in.packet);
}
} // while nbytes
// -----------------------------
// handle timers for generating data
// -----------------------------
if (!last_packet_initialize_ms || (now_ms - last_packet_initialize_ms >= 5000)) {
last_packet_initialize_ms = now_ms;
send_packet(MsgType_XP::Installation_Set);
} else if (!last_packet_PreFlight_ms || (now_ms - last_packet_PreFlight_ms >= 8200)) {
last_packet_PreFlight_ms = now_ms;
// TODO: allow callsign to not require a reboot
send_packet(MsgType_XP::Preflight_Set);
} else if (now_ms - last_packet_Operating_ms >= 1000 && (
last_packet_Operating_ms == 0 || // send once at boot
// send as data changes
last_operating_squawk != _frontend.out_state.cfg.squawk_octal ||
abs(last_operating_alt - _frontend._my_loc.alt) > 1555 || // 1493cm == 49ft. The output resolution is 100ft per bit
last_operating_rf_select != _frontend.out_state.cfg.rfSelect))
{
last_packet_Operating_ms = now_ms;
last_operating_squawk = _frontend.out_state.cfg.squawk_octal;
last_operating_alt = _frontend._my_loc.alt;
last_operating_rf_select = _frontend.out_state.cfg.rfSelect;
send_packet(MsgType_XP::Operating_Set);
} else if (now_ms - last_packet_GPS_ms >= (_frontend.out_state.is_flying ? 200 : 1000)) {
// 1Hz when not flying, 5Hz when flying
last_packet_GPS_ms = now_ms;
send_packet(MsgType_XP::GPS_Set);
}
}
void AP_ADSB_Sagetech::send_packet(const MsgType_XP type)
{
switch (type) {
case MsgType_XP::Installation_Set:
send_msg_Installation();
break;
case MsgType_XP::Preflight_Set:
send_msg_PreFlight();
break;
case MsgType_XP::Operating_Set:
send_msg_Operating();
break;
case MsgType_XP::GPS_Set:
send_msg_GPS();
break;
default:
break;
}
}
void AP_ADSB_Sagetech::request_packet(const MsgType_XP type)
{
// set all bytes in packet to 0 via {} so we only need to set the ones we need to
Packet_XP pkt {};
pkt.type = MsgType_XP::Request;
pkt.id = 0;
pkt.payload_length = 4;
pkt.payload[0] = static_cast<uint8_t>(type);
send_msg(pkt);
}
void AP_ADSB_Sagetech::handle_packet_XP(const Packet_XP &msg)
{
switch (msg.type) {
case MsgType_XP::ACK:
handle_ack(msg);
break;
case MsgType_XP::Installation_Response:
case MsgType_XP::Preflight_Response:
case MsgType_XP::Status_Response:
// TODO add support for these
break;
case MsgType_XP::ADSB_StateVector_Report:
case MsgType_XP::ADSB_ModeStatus_Report:
case MsgType_XP::TISB_StateVector_Report:
case MsgType_XP::TISB_ModeStatus_Report:
case MsgType_XP::TISB_CorasePos_Report:
case MsgType_XP::TISB_ADSB_Mgr_Report:
handle_adsb_in_msg(msg);
break;
case MsgType_XP::Installation_Set:
case MsgType_XP::Preflight_Set:
case MsgType_XP::Operating_Set:
case MsgType_XP::GPS_Set:
case MsgType_XP::Request:
// these are out-bound only and are not expected to be received
case MsgType_XP::INVALID:
break;
}
}
void AP_ADSB_Sagetech::handle_ack(const Packet_XP &msg)
{
// ACK received!
const uint8_t system_state = msg.payload[2];
transponder_type = (Transponder_Type)msg.payload[6];
const uint8_t prev_transponder_mode = last_ack_transponder_mode;
last_ack_transponder_mode = (system_state >> 6) & 0x03;
if (prev_transponder_mode != last_ack_transponder_mode) {
static const char *mode_names[] = {"OFF", "STBY", "ON", "ON-ALT"};
if (last_ack_transponder_mode < ARRAY_SIZE(mode_names)) {
gcs().send_text(MAV_SEVERITY_INFO, "ADSB: RF Mode: %s", mode_names[last_ack_transponder_mode]);
}
}
}
void AP_ADSB_Sagetech::handle_adsb_in_msg(const Packet_XP &msg)
{
AP_ADSB::adsb_vehicle_t vehicle {};
vehicle.last_update_ms = AP_HAL::millis();
switch (msg.type) {
case MsgType_XP::ADSB_StateVector_Report: { // 0x91
const uint16_t validFlags = le16toh_ptr(&msg.payload[8]);
vehicle.info.ICAO_address = le24toh_ptr(&msg.payload[10]);
if (validFlags & SAGETECH_VALIDFLAG_LATLNG) {
vehicle.info.lat = ((int32_t)le24toh_ptr(&msg.payload[20])) * SAGETECH_SCALER_LATLNG;
vehicle.info.lon = ((int32_t)le24toh_ptr(&msg.payload[23])) * SAGETECH_SCALER_LATLNG;
vehicle.info.flags |= ADSB_FLAGS_VALID_COORDS;
}
if (validFlags & SAGETECH_VALIDFLAG_ALTITUDE) {
vehicle.info.altitude = (int32_t)le24toh_ptr(&msg.payload[26]);
vehicle.info.flags |= ADSB_FLAGS_VALID_ALTITUDE;
}
if (validFlags & SAGETECH_VALIDFLAG_VELOCITY) {
const float velNS = ((int32_t)le16toh_ptr(&msg.payload[29])) * SAGETECH_SCALER_KNOTS_TO_CMS;
const float velEW = ((int32_t)le16toh_ptr(&msg.payload[31])) * SAGETECH_SCALER_KNOTS_TO_CMS;
vehicle.info.hor_velocity = Vector2f(velEW, velNS).length();
vehicle.info.flags |= ADSB_FLAGS_VALID_VELOCITY;
}
if (validFlags & SAGETECH_VALIDFLAG_HEADING) {
vehicle.info.heading = ((float)msg.payload[29]) * SAGETECH_SCALER_HEADING_CM;
vehicle.info.flags |= ADSB_FLAGS_VALID_HEADING;
}
if ((validFlags & SAGETECH_VALIDFLAG_V_RATE_GEO) || (validFlags & SAGETECH_VALIDFLAG_V_RATE_BARO)) {
vehicle.info.ver_velocity = (int16_t)le16toh_ptr(&msg.payload[38]);
vehicle.info.flags |= ADSB_FLAGS_VERTICAL_VELOCITY_VALID;
}
_frontend.handle_adsb_vehicle(vehicle);
break;
}
case MsgType_XP::ADSB_ModeStatus_Report: // 0x92
vehicle.info.ICAO_address = le24toh_ptr(&msg.payload[9]);
if (msg.payload[16] != 0) {
// if string is non-null, consider it valid
memcpy(&vehicle.info, &msg.payload[16], 8);
vehicle.info.flags |= ADSB_FLAGS_VALID_CALLSIGN;
}
_frontend.handle_adsb_vehicle(vehicle);
break;
case MsgType_XP::TISB_StateVector_Report:
case MsgType_XP::TISB_ModeStatus_Report:
case MsgType_XP::TISB_CorasePos_Report:
case MsgType_XP::TISB_ADSB_Mgr_Report:
// TODO
return;
default:
return;
}
}
// handling inbound byte and process it in the state machine
// return true when a full packet has been received
bool AP_ADSB_Sagetech::parse_byte_XP(const uint8_t data)
{
switch (message_in.state) {
default:
case ParseState::WaitingFor_Start:
if (data == 0xA5) {
message_in.state = ParseState::WaitingFor_AssmAddr;
}
break;
case ParseState::WaitingFor_AssmAddr:
message_in.state = (data == 0x01) ? ParseState::WaitingFor_MsgType : ParseState::WaitingFor_Start;
break;
case ParseState::WaitingFor_MsgType:
message_in.packet.type = static_cast<MsgType_XP>(data);
message_in.state = ParseState::WaitingFor_MsgId;
break;
case ParseState::WaitingFor_MsgId:
message_in.packet.id = data;
message_in.state = ParseState::WaitingFor_PayloadLen;
break;
case ParseState::WaitingFor_PayloadLen:
message_in.packet.payload_length = data;
message_in.index = 0;
message_in.state = (data == 0) ? ParseState::WaitingFor_ChecksumFletcher : ParseState::WaitingFor_PayloadContents;
break;
case ParseState::WaitingFor_PayloadContents:
message_in.packet.payload[message_in.index++] = data;
if (message_in.index >= message_in.packet.payload_length) {
message_in.state = ParseState::WaitingFor_ChecksumFletcher;
message_in.index = 0;
}
break;
case ParseState::WaitingFor_ChecksumFletcher:
message_in.packet.checksumFletcher = data;
message_in.state = ParseState::WaitingFor_Checksum;
break;
case ParseState::WaitingFor_Checksum:
message_in.packet.checksum = data;
message_in.state = ParseState::WaitingFor_End;
if (checksum_verify_XP(message_in.packet)) {
handle_packet_XP(message_in.packet);
}
break;
case ParseState::WaitingFor_End:
// we don't care if the end value matches
message_in.state = ParseState::WaitingFor_Start;
break;
}
return false;
}
// compute Sum and FletcherSum values into a single value
// returns uint16_t with MSByte as Sum and LSByte FletcherSum
uint16_t AP_ADSB_Sagetech::checksum_generate_XP(Packet_XP &msg) const
{
uint8_t sum = 0;
uint8_t sumFletcher = 0;
const uint8_t header_message_format[5] {
0xA5, // start
0x01, // assembly address
static_cast<uint8_t>(msg.type),
msg.id,
msg.payload_length
};
for (uint8_t i=0; i<5; i++) {
sum += header_message_format[i];
sumFletcher += sum;
}
for (uint8_t i=0; i<msg.payload_length; i++) {
sum += msg.payload[i];
sumFletcher += sum;
}
return UINT16_VALUE(sum, sumFletcher);
}
// computes checksum and returns true if it matches msg checksum
bool AP_ADSB_Sagetech::checksum_verify_XP(Packet_XP &msg) const
{
const uint16_t checksum = checksum_generate_XP(msg);
return (HIGHBYTE(checksum) == msg.checksum) && (LOWBYTE(checksum) == msg.checksumFletcher);
}
// computes checksum and assigns checksum values to msg
void AP_ADSB_Sagetech::checksum_assign_XP(Packet_XP &msg)
{
const uint16_t checksum = checksum_generate_XP(msg);
msg.checksum = HIGHBYTE(checksum);
msg.checksumFletcher = LOWBYTE(checksum);
}
// send message to serial port
void AP_ADSB_Sagetech::send_msg(Packet_XP &msg)
{
// generate and populate checksums.
checksum_assign_XP(msg);
const uint8_t message_format_header[5] {
0xA5, // start
0x01, // assembly address
static_cast<uint8_t>(msg.type),
msg.id,
msg.payload_length
};
const uint8_t message_format_tail[3] {
msg.checksumFletcher,
msg.checksum,
0x5A // end
};
if (_port != nullptr) {
_port->write(message_format_header, sizeof(message_format_header));
_port->write(msg.payload, msg.payload_length);
_port->write(message_format_tail, sizeof(message_format_tail));
}
}
void AP_ADSB_Sagetech::send_msg_Installation()
{
Packet_XP pkt {};
pkt.type = MsgType_XP::Installation_Set;
pkt.payload_length = 28; // 28== 0x1C
// Mode C = 3, Mode S = 0
pkt.id = (transponder_type == Transponder_Type::Mode_C) ? 3 : 0;
// // convert a decimal 123456 to 0x123456
// TODO: do a proper conversion. The param contains "131313" but what gets transmitted over the air is 0x200F1.
const uint32_t icao_hex = convert_base_to_decimal(16, _frontend.out_state.cfg.ICAO_id_param);
put_le24_ptr(&pkt.payload[0], icao_hex);
memcpy(&pkt.payload[3], &_frontend.out_state.cfg.callsign, 8);
pkt.payload[11] = 0; // airspeed MAX
pkt.payload[12] = 0; // COM Port 0 baud, fixed at 57600
pkt.payload[13] = 0; // COM Port 1 baud, fixed at 57600
pkt.payload[14] = 0; // COM Port 2 baud, fixed at 57600
pkt.payload[15] = 1; // GPS from COM port 0 (this port)
pkt.payload[16] = 1; // GPS Integrity
pkt.payload[17] = _frontend.out_state.cfg.emitterType / 8; // Emitter Set
pkt.payload[18] = _frontend.out_state.cfg.emitterType & 0x0F; // Emitter Type
pkt.payload[19] = _frontend.out_state.cfg.lengthWidth; // Aircraft Size
pkt.payload[20] = 0; // Altitude Encoder Offset
pkt.payload[21] = 0; // Altitude Encoder Offset
pkt.payload[22] = 0x07; // ADSB In Control, enable reading everything
pkt.payload[23] = 30; // ADSB In Report max length COM Port 0 (this one)
pkt.payload[24] = 0; // ADSB In Report max length COM Port 1
send_msg(pkt);
}
void AP_ADSB_Sagetech::send_msg_PreFlight()
{
Packet_XP pkt {};
pkt.type = MsgType_XP::Preflight_Set;
pkt.id = 0;
pkt.payload_length = 10;
memcpy(&pkt.payload[0], &_frontend.out_state.cfg.callsign, 8);
memset(&pkt.payload[8], 0, 2);
send_msg(pkt);
}
void AP_ADSB_Sagetech::send_msg_Operating()
{
Packet_XP pkt {};
pkt.type = MsgType_XP::Operating_Set;
pkt.id = 0;
pkt.payload_length = 8;
// squawk
// param is saved as native octal so we need convert back to
// decimal because Sagetech will convert it back to octal
uint16_t squawk = convert_base_to_decimal(8, last_operating_squawk);
put_le16_ptr(&pkt.payload[0], squawk);
// altitude
if (_frontend.out_state.cfg.rf_capable & 0x01) {
const float alt_meters = last_operating_alt * 0.01f;
const int32_t alt_feet = (int32_t)(alt_meters * FEET_TO_METERS);
const int16_t alt_feet_adj = (alt_feet + 50) / 100; // 1 = 100 feet, 1 = 149 feet, 5 = 500 feet
put_le16_ptr(&pkt.payload[2], alt_feet_adj);
} else {
// use integrated altitude - recommend by sagetech
pkt.payload[2] = 0x80;
pkt.payload[3] = 0x00;
}
// RF mode
pkt.payload[4] = last_operating_rf_select;
send_msg(pkt);
}
void AP_ADSB_Sagetech::send_msg_GPS()
{
Packet_XP pkt {};
pkt.type = MsgType_XP::GPS_Set;
pkt.payload_length = 52;
pkt.id = 0;
const int32_t longitude = _frontend._my_loc.lng;
const int32_t latitude = _frontend._my_loc.lat;
// longitude and latitude
// NOTE: these MUST be done in double or else we get roundoff in the maths
const double lon_deg = longitude * (double)1.0e-7 * (longitude < 0 ? -1 : 1);
const double lon_minutes = (lon_deg - int(lon_deg)) * 60;
snprintf((char*)&pkt.payload[0], 12, "%03u%02u.%05u", (unsigned)lon_deg, (unsigned)lon_minutes, unsigned((lon_minutes - (int)lon_minutes) * 1.0E5));
const double lat_deg = latitude * (double)1.0e-7 * (latitude < 0 ? -1 : 1);
const double lat_minutes = (lat_deg - int(lat_deg)) * 60;
snprintf((char*)&pkt.payload[11], 11, "%02u%02u.%05u", (unsigned)lat_deg, (unsigned)lat_minutes, unsigned((lat_minutes - (int)lat_minutes) * 1.0E5));
// ground speed
const Vector2f speed = AP::ahrs().groundspeed_vector();
float speed_knots = speed.length() * M_PER_SEC_TO_KNOTS;
snprintf((char*)&pkt.payload[21], 7, "%03u.%02u", (unsigned)speed_knots, unsigned((speed_knots - (int)speed_knots) * 1.0E2));
// heading
float heading = wrap_360(degrees(speed.angle()));
snprintf((char*)&pkt.payload[27], 10, "%03u.%04u", unsigned(heading), unsigned((heading - (int)heading) * 1.0E4));
// hemisphere
uint8_t hemisphere = 0;
hemisphere |= (latitude >= 0) ? 0x01 : 0; // isNorth
hemisphere |= (longitude >= 0) ? 0x02 : 0; // isEast
hemisphere |= (AP::gps().status() < AP_GPS::GPS_OK_FIX_2D) ? 0x80 : 0; // isInvalid
pkt.payload[35] = hemisphere;
// time
uint64_t time_usec;
if (AP::rtc().get_utc_usec(time_usec)) {
// not completely accurate, our time includes leap seconds and time_t should be without
const time_t time_sec = time_usec / 1000000;
struct tm* tm = gmtime(&time_sec);
// format time string
snprintf((char*)&pkt.payload[36], 11, "%02u%02u%06.3f", tm->tm_hour, tm->tm_min, tm->tm_sec + (time_usec % 1000000) * 1.0e-6);
} else {
memset(&pkt.payload[36],' ', 10);
}
send_msg(pkt);
}
/*
* Convert base 8 or 16 to decimal. Used to convert an octal/hexadecimal value stored on a GCS as a string field in different format, but then transmitted over mavlink as a float which is always a decimal.
* baseIn: base of input number
* inputNumber: value currently in base "baseIn" to be converted to base "baseOut"
*
* Example: convert ADSB squawk octal "1200" stored in memory as 0x0280 to 0x04B0
* uint16_t squawk_decimal = convertMathBase(8, squawk_octal);
*/
uint32_t AP_ADSB_Sagetech::convert_base_to_decimal(const uint8_t baseIn, uint32_t inputNumber)
{
// Our only sensible input bases are 16 and 8
if (baseIn != 8 && baseIn != 16) {
return inputNumber;
}
uint32_t outputNumber = 0;
for (uint8_t i=0; inputNumber != 0; i++) {
outputNumber += (inputNumber % 10) * powf(10, i);
inputNumber /= 10;
}
return outputNumber;
}
#endif // HAL_ADSB_SAGETECH_ENABLED