APM 2.5 plus the 3DR radio telemetry works great, now I want to add my MinimOSD board.
The MinimOSD board reads MAVLink messages from its RX pin and request rates from APM on the ArduPilot "telem" port. (Port 0 implied). The APM2.5 board 3DR radio connector (UART0/2) pin out from the board edge counting inward is: Gnd, (blank) RX, TX, +5V.
The MinimOSD Introduction has a diagram which states APM telemetry port (pins sequence from bottom) (shows bottom of block diagram of Port) This presumes that it is also board edge of back of APM2.5 and shows (APM pins) counting inward as: Gnd, (space) +5v, out, in. (out to rx of OSD, in to TX on OSD). The silk screen on the APM2.5 is clear, and I believe +5v is the most inside (away from edge) pin of Port 0. Should I just wire my OSD up based on what the APM says about Port 0 pins?
Is the diagram in MinimOSD introduction wrong on its cabling to APM telem port?
I am eager to add my MinimOSD to my build, but do not want to fry or brick my OSD.
Hope this helps someone in clearing this up somehow.
It would have been handy to have had another connector like 3DR for the feed to the MinimOSD.
In the meantime I guess I just hack into my 3DR cable or solder to tiny pins on back of APM2.5.
With this setup, will the OSD stop functioning if the aircraft flies out of range of the telemetry radios?
I'm a little confused as to why the TX is not connected or why it's been suggested to add a swtich?, this might be blatantly obvious if I had it all in front of me though.
Can someone provide the primary advantage for running MinimOSD in parallel with the 3DR telemetry data? Ideally you would have video coming back separately and combined at the ground station with the HUD. My 800mw 1.3 Ghz video link has better range than the 3DR telemetry link, so one reason to run both is that you might be out of telemetry range but still have a video link. Is that the only reason or are there other reasons?
It allows you to fly and still see the important stats that the OSD gives, without having to haul a ground station around everywhere.
I use both all the time. It's tough to tune the autopilot performance without telem and I find myself tweaking various things during flight fairly regularly. I can't imagine having to pull my APM out every time and plug into the USB. As you mentioned, an additional advantage to having minimOSD is that you get on screen telemetry info on your video feed even when out of range of the telem radios (arduplane). I am staying within the legal RC guidlines in the US, which is below 400ft AGL and within a 6000ft (1 nautical mile) euclidean radius and I am able to maintain telem most of the time. i fly with a monitor on a tripod and a laptop on a stand so I'm usually looking at the video and OSD and listening to the mission planner voice commands. It works well. I tried running just the 3DR telemetry for video feed using the MP HUD but found that the video was not fast/clear enough to frely on. It's too bad because I really like the MP HUD overlay.Also Mission planner only lets you record video at 5 frames per second, which is about 25 frames short of american standard. I am using easycap so that may play some part in the quality I am getting but through ulead software it looks good. Not sure if I'm answering your question...
I have minimosd v1.1. I have the solder points jumped and running off 12v battery. It's plugged into the apm 2.5. I can see video going thru fine but no osd. I mean nothing not just 0's but no graphics at all. Also i can see a tiny led labeled ST flashing rapidly. Any ideas? Thanks
If you connect the blobs, it seems that normally you would not connect the 12V, by not connecting the blobs you need the 12V line to power the MAX chip (via the onboard regulator)
I tried that as well. When I had 12v and 5v hooked up at the same time I got too much noise. So much that i completely lost the signal. But even then I saw no osd. Since I thought the noise was coming from the 5v line i thought the idea was to power only from a second battery. And I thought I saw a post where someone else successively powered from the 12v line.
Power from both,no blobs = video , but no osd, lots of noise
5v only with blobs = video, no osd, no noise
12v only with blobs = video, no osd, no noise
How do i get the osd?