Discussions

Dear All,

Firt...let me thank you guys working very hard with all these Ardu-things (ArduPilot, ArduCopter, APM, ...). Very nice and I love it!

I have bought a set of APC220 RF sender/receivers for using as telemtry link for my ArduCopter. I could not connect with the APM Mission Planner...got a time-out for "no heartbeat sent". It did however work with HK GCS and QGroundStation so I started to dig into why it did not work with APM. Luckily, the code is available and hence I have now managed to get it to work.

The APC220 requires the RTS and DTR to be false at all times as no handshaking can be used. I also found that the version of ArduCopter (2.4.1) that I have does not send heartbeats on the telemetry port...have I set something up badly here?

To get this to work you can edit the code to change how the OpenBg() is executed in the MavLink.cs according to:

lock (objlock) // so we dont have random traffic

{
log.Info("Open port with " + BaseStream.PortName + " " + BaseStream.BaudRate);

if (useAPC220)
{
// No RTS/DTR at all for this one...
BaseStream.RtsEnable = false;
BaseStream.DtrEnable = false;

BaseStream.Open();

BaseStream.DiscardInBuffer();
}
else
{
BaseStream.Open();

BaseStream.DiscardInBuffer();

BaseStream.toggleDTR();
}

Thread.Sleep(1000);
}

I added a small "useAPC220" propery that I set to "true".

I also added/changed a setting where the code expects the heartbeats to come:

if (useAPC220)
{
// No hearbeats coming from my 2.4.1 FW using APC220...why?
// firmware issue?
sysid = 1;
compid = 1;
mavlinkversion = 2;
aptype = 2;
break;
}
else
{
// incase we are in setup mode
BaseStream.WriteLine("planner\rgcs\r");

buffer = getHeartBeat();

// incase we are in setup mode
BaseStream.WriteLine("planner\rgcs\r");

System.Threading.Thread.Sleep(1);

buffer1 = getHeartBeat();
}

So, I hardcoded some values (version, id's etc) that is coming from the heartbeat package normally.

Anyhow, this is a rather bad approach (but quick and dirty and works for my special case). So, now I wonder if it would be possible to add a few settings in the APM Mission Planner to handle this? Maybe one can have a setting for "use handshake" and one for "expect heartbeat". This would make the APM to be compatible with the APC220 as well.

Well...that was what I had in mind. Thanx once again for your hard work!

/Stefan