#go-mavlink
go impletation of the MAVLink protocol.
MAVLink or Micro Air Vehicle Link is a protocol for communicating with small unmanned vehicle. It's designed as a header-only message marshaling library. MAVLink was first released early 2009 by Lorenz Meier under LGPL license.
This implementation is mainly inspired by the C version (see on GitHub). Only tested under Unix
#Usage
Here two quick examples to understand how to deal with it but first, look at the MavPacket definition.
###MavPacket definition :
type Message interface {
ID() uint8
Size() uint8
}
type MavHeader struct {
FrameStart uint8
PayloadLength uint8
PacketSequence uint8
SystemID uint8
ComponentID uint8
MessageID uint8
}
type MavPacket struct {
Header MavHeader
Msg Message
Checksum uint16
}You got all the message definitions in message.go.
##UDP communication (receiving example)
package main
import (
"bufio"
"fmt"
mav "github.com/Sabmit/go-mavlink"
"log"
"net"
)
func main() {
laddr, _ := net.ResolveUDPAddr("udp", "127.0.0.1:14550")
conn, _ := net.ListenUDP("udp", laddr) // check errors
parser := mav.GetMavParser()
reader := bufio.NewReader(conn)
for {
c, _ := reader.ReadByte() // check errors
packet, err := parser(c)
if err != nil {
log.Fatalf("Parser error: ", err)
} else if packet != nil {
fmt.Println("Packet received :", packet.Bytes())
}
}
}The C server is available here, you can also test it by hand...
$ echo -ne "\xfe\x09\x0\x01\xC8\x00\x0\x0\x0\x0\x0\x0\x0\x0\x0\x5A\x3E" | nc -u 127.0.0.1 14550##Serial communication (Sending example)
import (
"github.com/tarm/goserial"
mav "github.com/Sabmit/go-mavlink"
"log"
)
func main() {
port := &serial.Config{Name: "/dev/ttyUSB0", Baud: 57600}
s, _ := serial.OpenPort(port) // check errors
message := new(mav.RequestDataStream)
message.ReqMessageRate = 20
err := mav.Send(s, 1, 200, message)
if err != nil {
log.Fatalf("Error while sending the packet:", err)
}
}##More The operation is simple : get the MavParser and then, parse each received byte untill you get a non-nil pointer pointing to the full MavPacket.
Please read main_udp.go and main_serial.go if you want the full code examples.
#TO-DO
- For now, only the received packet has its own checksum computed on the go
- Verify if all properties of each message is in its own place (see Mavlink generator)
#See
#Authors