"Hi, what exactly are you trying to find out - how to activate altitude hold or what are the implementation details?

There is a new version available. You will need to configure the hover throttle before using altitude hold."

"I've updated the installation scripts and readme.
Compile instructions you will find in the README:
https://github.com/rpicopter/buildroot"

"Hi, How is it going, is it already flying?"

"Hi,

This is not Raspbian what we are using. It is a custom build linux distribution. 
I will do a writeup of how to compile it if I get some time but the basic steps are in here:
https://github.com/rpicopter/buildroot"

"Depends on what exactly you want to do. Check the AvrMiniCopter architecture: https://github.com/rpicopter/AvrMiniCopter-wiki/wiki/Design

If you want to hack the code that controls the quadcopter then you only need Arduino IDE. However if you want…"

"You can adjust PID realtime through 'WS Debug' or through command line.
Just send a command with the new PID value, for example:
'112 500' to set rate pid Kp to 500 for pitch

For the full list see lines 279-311…"

"Did you adjust acro and stab PIDs? You first need to make it fly well in a stab/acro mode before trying to tweek altitude hold mode. Do you have experience in other quadcopter controllers like MultiWii, ArduCopter, naza, etc?"

"I should have added - To engage althold you will need to hover in place and press the x button. Only then you can let the throttle go.

In the next weeks I will be submitting a new version where you can use althold to self start and self land."

"Looks good. I would not worry about slight Baro movements. You will need to test fly to see and adjust parameters. You might want to read the ArduCopter altitude hold manual. It gives good overview of what parameters should be adjusted."

"What are you trying to debug?
You just need to send a command. List of commands is in the help on the screen. You might also want to clear the filter there."

"Have you test fly with altitude hold? Can you take a video?"

"Bmp085 Barometer has a tolerance of around 30cm. From my experience this actually is usually around +/-50 cm.
To ease barometer errors you will need to protect it from direct sunlight and wind.

You can also adjust Baro constant in the WWW. Take a…"

"Which controller are you using, are you using PS3 connected to Android device? or PS3 over bluetooth?

For android + PS3 check: https://github.com/rpicopter/AvrMiniCopter-Android/wiki/Controls
For PS3 over bluetooth…"

"Hi, I can confirm that ralink rt5370 works fine."

"You do not have to use barometer. You can use any other altitude estimation. Using arduino means we would need to write all the different drivers. In this case you might want to look into MultiWii.
AvrMiniCopter vision is to be a minimalistic…"

"Yes and no. Rpi reads altitude and passes it over to avr for processing."