Telemetry +bluetooth = MP stuck at "Getting Params"

Hello everybody,

I just joined the communityand I hope i can get some help from you guys.

I have researched the internets on this topics and could not find a definitive answer so here it goes:

I bought a telemetry and bluetooth module (hc-05) from ebay a week ago. for the past two days i was trying to get them too work with MissionPlanner. The telemetry unit works great and connects to MP no problem. USB also works for connecting to MP.

My ground module has a USB port, and there is no easy way to connect the bluetooth to it. So what i did, i soldered 2 wires directly to the HM-TRP (RX and TX) and got my 5V and GND from the outer USB connections (it later translates to 3.3V for the HM-TRP board). I connected the two wires (rx and tx) to my bluetooth module (already configured to 57600) and separately powered it up.

Now the problem arises when i try to connect. I would get my heartbeat and all the statuses working ( yaw pitch distance, height etc) but i would never get the parameters. it gets stuck at “Getting Params”. i checked the status and saw that a lot of packets were lost.

I have tried unclicking the “reset APM on USB” and that doesnt do anything. The only way I got the parameters to download was to connect the ground module USB to one computer, and the bluetooth to another computer, both tunning MP, i would connect the bluetooth one first until it gets stuck at the getting params, then I would connect the USB one. what happened is that as soon as the USB connection started loading the parameters, so did the bluetooth one. Makes me question if the Bt module cant send a request to receive parameters or something of the sort.

Any help would be appreciated.

check your wiring. it sounds like the wire from your bluetooth tx pin to radio rx pin is not connected, either that or the wire from your apms rx pin is not connected to your radios tx pin.