By putting the OSD information in the video on the ground it will remain on the display if the video from the transmitter is interrupted. Also when the Tx signal gets weak the OSD info will remain clear.
How would you go about getting the Mavlink data out of the ground based Xbee to the MimimOSD?
Right now I have a XtreamBee USB adapter on the ground. Can I just change that to a FTDI board (same one as airborne), parallel the data between the MimimOSD and a FTDI to USB cable? Will Tx/Rx lines need to be swapped? The USB cable would then plug into the computer running the Mission Planner.
Any help is appreciated.
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I am in the process of selecting components for my system and was zeroing in on the video system from Range Video. Their package price seems to have come down, but the camera resolution is given as 600 TVL. After reading this thread, it sounds like I might have trouble using this with MinimOSD. Do you think that's the case, that it won't work?
Thanks,
Paul
Today I was able to bench test this setup. Using an XtreamBee FTDI adapter on the ground, I paralleled the data to the Minimum OSD and the FTDI/USB cable. The USB cable fed the computer running the mission planner. I did have to roll the Rx wire on OSD to get the both the OSD and mission planner to respond properly.
I discovered another limitation that may make putting the MinimOSD on the ground a moot point. As the video signal from the plane gets weaker the MinimOSD will blank the OSD information from the display. If the video from the plane completly goes away, then the OSD info shows up on a black screen. I can only guess the MinimOSD can not frame both the data and the video if the video starts getting weak. Without adding more video processing hardware on the ground, the MinimOSD is going back on the plane.
Anyway, what I have done is to use an xstreambee adapter on the ground, with the 900mhz xbee. I soldered extra long pins to it so I can connect an FTDI to USB cable to it. This provides power and allows me use the mission planner in parallel.
With the extra long pins I can plug jumpers to the other side of the pins to take 5v, ground and data out to minimosd.
I have soldered the pads on the minimosd so it is all powered from the USB/FTDI cable (5v). I created some rc connectors to RCA plugs so I can connect my rx and goggles to the minimosd.
This is where I am currently having problems. If I plug in the goggles only on the video output side, I can see the OSD perfectly on a black background. All the data is flowing through just fine. When I plug in the Rx to the minimosd video input I lose the OSD and only get video.
Thats where I am at right now. I'm sure is solvable, just need to keep plugging away. Hardware is not my area of expertise, but looking at some other forums, it could be the voltage i am supplying to the max7456 chip (min 4.75v, but my usb only puts out 4.85, so could be cutting it fine) or it could be something about how the rx and goggles are grouded (needs to share the same ground) or it could be something else. I hope one of the gurus around here might be able to help.
Regards
James