# Architecture * [PX4 Architectural Overview](https://dev.px4.io/en/concept/architecture.html) ```bash user@workstation:~$ cd src/ user@workstation:~/src$ cd Firmware/ user@workstation:~/src/Firmware$ ``` ```bash user@workstation:~/src/Firmware$ ls build Documentation LICENSE README.md circle.yml eclipse.cproject Makefile ROMFS cmake eclipse.project mavlink src CMakeLists.txt Firmware.sublime-project msg test_data CODE_OF_CONDUCT.md Images nuttx-configs Tools CONTRIBUTING.md integrationtests package.xml Vagrantfile CTestConfig.cmake Jenkinsfile platforms Debug launch posix-configs user@workstation:~/src/Firmware$ ``` ```bash user@workstation:~/src/Firmware$ cat .git/config [core] repositoryformatversion = 0 filemode = true bare = false logallrefupdates = true [remote "origin"] url = https://github.com/PX4/Firmware.git fetch = +refs/heads/*:refs/remotes/origin/* [branch "master"] remote = origin merge = refs/heads/master [submodule "src/lib/ecl"] url = https://github.com/PX4/ecl.git [submodule "src/lib/matrix"] url = https://github.com/PX4/Matrix.git [submodule "Tools/gencpp"] url = https://github.com/ros/gencpp.git [submodule "Tools/genmsg"] url = https://github.com/ros/genmsg.git [submodule "src/lib/DriverFramework"] url = https://github.com/PX4/DriverFramework.git [submodule "src/drivers/gps/devices"] url = https://github.com/PX4/GpsDrivers.git [submodule "mavlink/include/mavlink/v2.0"] url = https://github.com/mavlink/c_library_v2.git [submodule "mavlink/include/mavlink/v1.0"] url = https://github.com/mavlink/c_library_v1.git [submodule "Tools/sitl_gazebo"] url = https://github.com/PX4/sitl_gazebo.git [submodule "Tools/jMAVSim"] url = https://github.com/PX4/jMAVSim.git user@workstation:~/src/Firmware$ ``` ```bash user@workstation:~/src/Firmware$ ls src/ drivers examples firmware include lib modules platforms systemcmds user@server:~/src/Firmware$ ls src/drivers/ adis16448 drv_batt_smbus.h drv_pwm_trigger.h l3gd20 navio_rgbled sdp3x_airspeed aerofc_adc drv_blinkm.h drv_px4flow.h led navio_sysfs_rc_in sf0x airspeed drv_board_led.h drv_range_finder.h linux_gpio ocpoc_adc sf1xx batt_smbus drv_device.h drv_rc_input.h linux_pwm_out oreoled snapdragon_pwm_out blinkm drv_gpio.h drv_sbus.h linux_sbus pca8574 snapdragon_rc_pwm bma180 drv_gps.h drv_sensor.h lis3mdl pca9685 spektrum_rc bmi055 drv_gyro.h drv_tone_alarm.h ll40ls protocol_splitter srf02 bmi160 drv_hrt.h ets_airspeed lps25h pwm_input srf02_i2c bmm150 drv_input_capture.h frsky_telemetry lsm303d pwm_out_rc_in stm32 bmp280 drv_io_expander.h fxas21002c mb12xx pwm_out_sim tap_esc boards drv_iridiumsbd.h fxos8701cq md25 px4flow teraranger bootloaders drv_irlock.h gps mkblctrl px4fmu test_ppm bst drv_led.h hc_sr04 mpl3115a2 px4io ulanding camera_trigger drv_mag.h hmc5883 mpu6000 qshell vmount device drv_mixer.h hott mpu9250 rgbled drv_accel.h drv_orb_dev.h iridiumsbd ms4525_airspeed rgbled_pwm drv_adc.h drv_oreoled.h irlock ms5525_airspeed roboclaw drv_airspeed.h drv_pwm_input.h ist8310 ms5611 rpi_rc_in drv_baro.h drv_pwm_output.h kinetis navio_adc samv7 ``` ```bash user@workstation:~/src/Firmware$ ls src/examples/ bottle_drop hwtest publisher px4_mavlink_debug rover_steering_control subscriber fixedwing_control matlab_csv_serial px4_daemon_app px4_simple_app segway uuv_example_app ``` ```bash user@server:~/src/Firmware$ ls src/firmware/ nuttx posix qurt ``` ## Directory src/ ```bash user@workstation:~/src/Firmware$ ls src/include/ containers px4.h unit_test.h visibility.h ``` ```bash user@server:~/src/Firmware$ ls src/lib/ controllib ecl launchdetection matrix rc terrain_estimation conversion geo led mixer runway_takeoff version DriverFramework geo_lookup mathlib px4_eigen.h tailsitter_recovery ``` ```bash user@workstation:~/src/Firmware$ ls src/modules/ attitude_estimator_q fw_att_control load_mon micrortps_bridge sdlog2 uavcanesc camera_feedback fw_pos_control_l1 local_position_estimator muorb sensors uavcannode commander gnd_att_control logger navigator simulator uORB dataman gnd_pos_control mavlink position_estimator_inav syslink vtol_att_control ekf2 gpio_led mc_att_control px4iofirmware systemlib events land_detector mc_pos_control replay uavcan ``` ```bash user@workstation:~/src/Firmware$ ls src/platforms/ apps.cpp.in posix px4_getopt.h px4_micro_hal.h px4_posix.h px4_spi.h qurt apps.h.in px4_app.h px4_i2c.h px4_middleware.h px4_publisher.h px4_subscriber.h ros common px4_common.h px4_includes.h px4_module.h px4_sem.h px4_tasks.h shmem.h empty.c px4_config.h px4_log.h px4_nodehandle.h px4_sem.hpp px4_time.h nuttx px4_defines.h px4_message.h px4_parameter.h px4_shutdown.h px4_workqueue.h ``` ```bash user@workstation:~/src/Firmware$ ls src/systemcmds/ bl_update esc_calib mixer mtd perf reflect top ver config hardfault_log motor_ramp nshterm pwm sd_bench topic_listener dumpfile led_control motor_test param reboot tests usb_connected user@workstation:~/src/Firmware$ ``` ## Directory nuttx-configs/ ```bash user@workstation:~/src/Firmware$ ls nuttx-configs/ aerocore2 esc35-v1 PX4_Config.mk px4fmu-v4 px4nucleoF767ZI-v1 s2740vc-v1 aerofc-v1 mindpx-v2 px4esc-v1 px4fmu-v4pro px4-same70xplained-v1 tap-v1 auav-x21 nxphlite-v3 px4flow-v2 px4fmu-v5 px4-stm32f4discovery zubaxgnss-v1 crazyflie px4cannode-v1 px4fmu-v2 px4io-v2 PX4_Warnings.mk ``` ## Directory posix-configs/ ```bash user@workstation:~/src/Firmware$ ls posix-configs/ bebop eagle excelsior ocpoc rpi SITL user@workstation:~/src/Firmware$ ``` ```bash user@workstation:~/src/Firmware$ nano posix-configs/SITL/init/rcS_gazebo_delta_wing uorb start param load param set MAV_TYPE 1 param set SYS_AUTOSTART 3033 param set SYS_RESTART_TYPE 2 dataman start param set BAT_N_CELLS 3 param set CAL_GYRO0_ID 2293768 param set CAL_ACC0_ID 1376264 param set CAL_ACC1_ID 1310728 param set CAL_MAG0_ID 196616 param set CAL_GYRO0_XOFF 0.01 param set CAL_ACC0_XOFF 0.01 param set CAL_ACC0_YOFF -0.01 param set CAL_ACC0_ZOFF 0.01 param set CAL_ACC0_XSCALE 1.01 param set CAL_ACC0_YSCALE 1.01 param set CAL_ACC0_ZSCALE 1.01 param set CAL_ACC1_XOFF 0.01 param set CAL_MAG0_XOFF 0.01 param set SENS_BOARD_ROT 8 param set SENS_DPRES_OFF 0.001 param set SENS_BOARD_X_OFF 0.000001 param set COM_RC_IN_MODE 1 param set NAV_DLL_ACT 2 param set NAV_ACC_RAD 15.0 param set FW_THR_IDLE 0.6 param set FS_GCS_ENABLE 2 replay tryapplyparams simulator start -s tone_alarm start gyrosim start accelsim start barosim start adcsim start gpssim start measairspeedsim start pwm_out_sim mode_pwm sensors start commander start navigator start ekf2 start fw_pos_control_l1 start fw_att_control start land_detector start fixedwing mixer load /dev/pwm_output0 ../../../../ROMFS/sitl/mixers/delta_wing_sitl.main.mix mavlink start -x -u 14556 -r 2000000 mavlink start -x -u 14557 -r 2000000 -m onboard -o 14540 mavlink stream -r 80 -s POSITION_TARGET_LOCAL_NED -u 14556 mavlink stream -r 80 -s LOCAL_POSITION_NED -u 14556 mavlink stream -r 80 -s GLOBAL_POSITION_INT -u 14556 mavlink stream -r 80 -s ATTITUDE -u 14556 mavlink stream -r 80 -s ATTITUDE_QUATERNION -u 14556 mavlink stream -r 80 -s ATTITUDE_TARGET -u 14556 mavlink stream -r 20 -s RC_CHANNELS -u 14556 mavlink stream -r 250 -s HIGHRES_IMU -u 14556 mavlink stream -r 10 -s OPTICAL_FLOW_RAD -u 14556 logger start -e -t mavlink boot_complete replay trystart ``` ## Directory Images/ ```bash user@workstation:~/src/Firmware$ ls Images/ aerocore2.prototype mindpx-v2.prototype px4fmu-v2.prototype px4io-v2.prototype tap-v1.prototype aerofc-v1.prototype nxphlite-v3.prototype px4fmu-v3.prototype px4nucleoF767ZI-v1.prototype zubaxgnss-v1.prototype auav-x21.prototype px4cannode-v1.prototype px4fmu-v4pro.prototype px4-same70xplained-v1.prototype crazyflie.prototype px4esc-v1.prototype px4fmu-v4.prototype px4-stm32f4discovery.prototype esc35-v1.prototype px4flow-v2.prototype px4fmu-v5.prototype s2740vc-v1.prototype user@workstation:~/src/Firmware$ ``` ```bash user@workstation:~/src/Firmware$ cat Images/aerocore2.prototype { "board_id": 98, "magic": "AeroCore2", "description": "Firmware for the Gumstix AeroCore2 board", "image": "", "build_time": 0, "summary": "AEROCORE2", "version": "0.1", "image_size": 0, "git_identity": "", "board_revision": 0 } user@workstation:~/src/Firmware$ ``` ## Directory mavlink/ ```bash user@workstation:~/src/Firmware$ ls mavlink/include/mavlink/v2.0/ ardupilotmega checksum.h mavlink_conversions.h mavlink_sha256.h minimal standard ASLUAV common mavlink_get_info.h mavlink_types.h protocol.h test autoquad matrixpilot mavlink_helpers.h message_definitions slugs uAvionix user@workstation:~/src/Firmware$ ``` --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. 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