"Here is where I read about the software interface:
http://dev.3dr.com/hardware-gimbalbay.html#software-interface"

"Here are logs for 3.2.1 and a 3.3 tests. This particular 3.3 test drifted 5 meters.2015-04-01 15-15-44-fm-3.2.1.log2015-03-31 20-41-22-fw-3.3.log"

"For 3.3, the initial pre-arm calibration doesn't seem to bring the altitude to 0 and the altitude goes very (10-20m) negative during hover testing. I'll post a log of my test with 3.3."

"Thanks for the response. I did get it to work. Here are a couple of things that threw me off:

1.) rssi in the rc_channels_raw message had to be divided by 255 and then multiplied by the rssi_range. I was expecting a number between 0 and 100. The…"

"If I specify that RSSI_PIN=103 and RSSI_RANGE=5 and then connect a 1.5 V battery between the ground pins and the sensor pin on the SB slot of the Pixhawk, shouldn't I see an RSSI of 30 in the RC_CHANNELS_RAW message? Right now, I'm seeing a small…"

"BTW, during my ground hover testing, I noticed that the altitude is varying by 10-20 meters for the latest 3.3 version. It seems much better in the 3.2.1 release with a variation of about a meter during hover."

"Andy,
Thanks so much, that was the problem. I've never had to muck with this setting and didn't even know it existed. I guess I need to read the entire Spektrum manual to see what else I'm missing!…"

"I tried this test out with 3.2.1 on my APM with a Spektrum AR5200 receiver and DX7 Transmitter. It responded correctly by setting rc3 to 900 when the R/C transmitter was turned off.

Has anybody with a Pixhawk seen the behavior described above where…"

"I posted this on the other related thread, but haven't heard back:
http://diydrones.com/profiles/blog/show?id=705844%3ABlogPost%3A1903...

I've done tests with 3.2.1 and 3.3 and find that the rc channels continue to register values above 1000 when I…"

"Chad, I am using a Spektrum satellite receiver as well. Did you have to remap the throttle and pitch channels to get things working correctly? I had to use the RCMAP settings to swap pitch and throttle, but given the bugs in the Arducopter firmware…"

"I may have had a race condition that caused the issue.  I tried an experiment where I issued a mission_clear_all and then immediately set the mode to AUTO and got the firmware to go into AUTO. (If I had an empty mission to start with, I could not…"

"With the issues with the barometer and GPS, especially close to the ground, it seems like lidar or radar would be a more reliable solution for altitude measurements. I noticed that 3DR has a lidar coming that looks…"

"Thanks for your support Randy, you've been a great help over the years!  Its been great to see the project flourish!

I actually told the copter to LAND myself as well with MAVLINK then the pilot with the R/C switched it to RTL. (Switching to…"