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Source: drivers/telemetry/frsky_telemetry
FrSky 통신을 지원합니다. D, S.PORT 프로토콜을 자동으로 감지합니다.
frsky_telemetry <command> [arguments...]
Commands:
start
[-d <val>] Select Serial Device
values: <file:dev>, default: /dev/ttyS6
[-t <val>] Scanning timeout [s] (default: no timeout)
default: 0
[-m <val>] Select protocol (default: auto-detect)
values: sport|sport_single|sport_single_invert|dtype, default:
auto
stop
status
Source: modules/mavlink
이 모듈은 시리얼 통신이나 UDP 통신에 사용할 수 있는 MAVLink 프로토콜 구현체입니다. uORB로 시스템과 통신합니다. 일부 메시지는 모듈에서 직접 처리합니다(예: mission protocol), 다른 메세지는 uORB로 처리합니다(예: vehicle_command).
기체 자세와 같은 주기 메세지는 일정 속도로 내보냅니다. mavlink 인스턴스를 시작할 때, 자체 속도로 송수신하는 활성 스트림을 정의한 모드를 지정할 수 있습니다. 실행 인스턴스에 대해 mavlink stream 명령으로 스트림을 설정할 수 있습니다.
직렬 통신 장치나 네트워크 포트에 연결한 다중 독립 인스턴스가 있을 수 있습니다.
송신 스레드, 수신 스레드 각각 하나씩 2개로 구현했습니다. 송신 스레드는 일정한 속도로 실행하며, 설정 속도(-r)보다 대역폭이 높거나, 물리 연결 회선이 포화 상태가 되면 스트림 전송 속도를 동적으로 줄입니다. mavlink status 명령러를 통해 확인할 수 있습니다. rate mult가 1보다 작은지 보세요.
Careful: 일부 데이터는 양쪽 스레드에서 접근하고 수정합니다. 코드를 바꾸거나 기능을 확장할 경우 경쟁 상태(race condition)로의 진입과 데이터 유실을 피하기 위한 검토가 필요합니다.
ttyS1에 전송율 초당 921600비트, 최대 전송속도 80kB/s로 mavlink를 시작합니다.
mavlink start -d /dev/ttyS1 -b 921600 -m onboard -r 80000
UDP 포트 14556에 HIGHRES_IMU 메시지를 초당 50번 전송하도록 설정하며 mavlink를 시작합니다.
mavlink start -u 14556 -r 1000000
mavlink stream -u 14556 -s HIGHRES_IMU -r 50
mavlink <command> [arguments...]
Commands:
start Start a new instance
[-d <val>] Select Serial Device
values: <file:dev>, default: /dev/ttyS1
[-b <val>] Baudrate (can also be p:<param_name>)
default: 57600
[-r <val>] Maximum sending data rate in B/s (if 0, use baudrate / 20)
default: 0
[-u <val>] Select UDP Network Port (local)
default: 14556
[-o <val>] Select UDP Network Port (remote)
default: 14550
[-t <val>] Partner IP (broadcasting can be enabled via MAV_BROADCAST
param)
default: 127.0.0.1
[-m <val>] Mode: sets default streams and rates
values:
custom|camera|onboard|osd|magic|config|iridium|minimal|extvsisi
on, default: normal
[-n <val>] wifi/ethernet interface name
values: <interface_name>
[-c <val>] Multicast address (multicasting can be enabled via
MAV_BROADCAST param)
values: Multicast address in the range
[239.0.0.0,239.255.255.255]
[-f] Enable message forwarding to other Mavlink instances
[-w] Wait to send, until first message received
[-x] Enable FTP
[-z] Force hardware flow control always on
[-Z] Force hardware flow control always off
stop-all Stop all instances
status Print status for all instances
[streams] Print all enabled streams
stream Configure the sending rate of a stream for a running instance
[-u <val>] Select Mavlink instance via local Network Port
[-d <val>] Select Mavlink instance via Serial Device
values: <file:dev>
-s <val> Mavlink stream to configure
-r <val> Rate in Hz (0 = turn off, -1 = set to default)
boot_complete Enable sending of messages. (Must be) called as last step in
startup script.
Source: modules/micrortps_bridge/micrortps_client
micrortps_client <command> [arguments...]
Commands:
start
[-t <val>] Transport protocol
values: UART|UDP, default: UART
[-d <val>] Select Serial Device
values: <file:dev>, default: /dev/ttyACM0
[-b <val>] Baudrate (can also be p:<param_name>)
default: 460800
[-p <val>] Poll timeout for UART in ms
[-l <val>] Limit number of iterations until the program exits
(-1=infinite)
default: 10000
[-w <val>] Time in ms for which each iteration sleeps
default: 1
[-r <val>] Select UDP Network Port for receiving (local)
default: 2019
[-s <val>] Select UDP Network Port for sending (remote)
default: 2020
[-i <val>] Select IP address (remote)
values: <x.x.x.x>, default: 127.0.0.1
[-f] Activate UART link SW flow control
[-h] Activate UART link HW flow control
[-v] Add more verbosity
stop
status
Source: modules/uORB
uORB is the internal pub-sub messaging system, used for communication between modules.
It is typically started as one of the very first modules and most other modules depend on it.
No thread or work queue is needed, the module start only makes sure to initialize the shared global state. Communication is done via shared memory. The implementation is asynchronous and lock-free, ie. a publisher does not wait for a subscriber and vice versa. This is achieved by having a separate buffer between a publisher and a subscriber.
The code is optimized to minimize the memory footprint and the latency to exchange messages.
The interface is based on file descriptors: internally it uses read, write and ioctl. Except for the publications, which use orb_advert_t handles, so that they can be used from interrupts as well (on NuttX).
Messages are defined in the /msg directory. They are converted into C/C++ code at build-time.
If compiled with ORB_USE_PUBLISHER_RULES, a file with uORB publication rules can be used to configure which modules are allowed to publish which topics. This is used for system-wide replay.
Monitor topic publication rates. Besides top, this is an important command for general system inspection:
uorb top
uorb <command> [arguments...]
Commands:
start
status Print topic statistics
top Monitor topic publication rates
[-a] print all instead of only currently publishing topics with
subscribers
[-1] run only once, then exit
[<filter1> [<filter2>]] topic(s) to match (implies -a)