## 使用硬體 pixhawk、 Raspi
Raspberry pi5
python venv
install pymavlink
pixhawk 6x connect use usb or uart

[Companion Computers Communicating with Raspberry Pi via MAVLink](https://ardupilot.org/dev/docs/raspberry-pi-via-mavlink.html)

listen.py
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from pymavlink import mavutil
the_connection = mavutil.mavlink_connection("/dev/ttyACM0")
the_connection.wait_heartbeat()
print("Heartbeat from system (system %u component %u)" % (the_connection.target_system, the_connection.target_component))
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(yolov7) richard@raspberrypi5:~/pymavlink $ python listen.py 
Heartbeat from system (system 1 component 0)

連線成功的輸出如下圖
使用 mavproxy.py 的輸出如下圖
mavlink_connection()參數:
connection string:

從 pixhawk 收資訊:

# listen.py
from pymavlink import mavutil
import time
the_connection = mavutil.mavlink_connection('/dev/ttyACM1')
# 'udpin:localhost:14550'
# '/dev/ttyACM0'   
the_connection.wait_heartbeat()
print("Heartbeat from system (system %u component %u)" % (the_connection.target_system, the_connection.target_component))
# the_connection.mav.system_time_send(int(time.time()), int(time.time()))
while 1:
    msg = the_connection.recv_match(type='SYS_STATUS', blocking=True)
    print(msg)


## 如何使用虛擬環境 sim_vehcile.py & sitl
安裝: ardupilot & submodule
git clone https://github.com/ArduPilot/ardupilot.git
安裝 submodule (因為ardupilot github裡面沒有這些submodule)
git submodule update --recursive
git submodule init
安裝後才能執行 sim_vehcile.py
執行後如下

執行 mavproxy.py
執行 listen.py

from pymavlink import mavutil
the_connection = mavutil.mavlink_connection('udpin:localhost:14550')
the_connection.wait_heartbeat()
print("Heartbeat from system (system %u component %u)" % (the_connection.target_system, the_connection.target_component))


## sim_7600x
minicom -D /dev/ttyUSB3

## usbcam
install picamera2
https://datasheets.raspberrypi.com/camera/picamera2-manual.pdf

sudo apt install -y python3-picamera2
...

注意: picamera2 對 usb 的支援有限制，需進一步測試!