Could someone please explain packet 66 of the MAVLINK Protocol for requesting data streams? For example
the structure is as followed:
target_system | uint8_t | The target requested to send the message stream. |
target_component | uint8_t | The target requested to send the message stream. |
req_stream_id | uint8_t | The ID of the requested data stream |
req_message_rate | uint16_t | The requested interval between two messages of this type |
start_stop | uint8_t | 1 to start sending, 0 to stop sending. |
I would like clarified where is the target requested system documentation and what is this? Also, below is an attached snippet of the request messages the ardupilot mission planner makes before it starts its heartbeat and after its parameter request.
The 66 message (42 in hex) can be seen...followed by 02 or 03 or 0A...what targets are these? Also, the ID of the requested stream makes no sense...say I want attitude...why not request id 30...it appears the APMP makes requests to 01 which would suggest system status???
Lastly, what are the units of the requested interval ??? ms hz second etc
Thanks,
Generic Parameter Request
FE06D1FFBE4202000101020128E4
FE06D2FFBE420200010102019B1A
FE06D3FFBE42030001010601BEB3
FE06D4FFBE420300010106015813
FE06D5FFBE420A0001010A0153A2
FE06D6FFBE420A0001010A01E05C
FE06D7FFBE420A0001010B01AD53
FE06D8FFBE420A0001010B01E14F
FE06D9FFBE42020001010C019948
FE06DAFFBE42020001010C012AB6
FE06DBFFBE42020001010101C41C
FE06DCFFBE4202000101010122BC
FE06DDFFBE420200010103010B5C
FE06DEFFBE42020001010301B8A2
Heartbeat
Replies
Según la anatomía del paquete, ese campo es para referenciar el ID Message; para este caso, el 42 significa:
MISSION_CURRENT ( #42 )
Message that announces the sequence number of the current active mission item. The MAV will fly towards this mission item.
Revisar las siguientes páginas, donde se encuentra todo claro:
http://qgroundcontrol.org/mavlink/start
https://pixhawk.ethz.ch/mavlink/