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Raspberry Pi: reset external I2C devices (not only I2C)
Electronic, and specially computerized, devices likes to hang from time to time. There are many reasons: software bug, hardware error, voltage drop, interference, too long wire, random incident. I’ve learned this hard way during work on my Raspberry Pi based weather station. From time to time external DTH22 temperature/humidity sensor refused to work. Only solution…
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Detecting Betaflight PID tuning issues with Blackbox: excess P gain
Almost all quadcopter PID tuning tutorials can be summarized into one sentence: “Increase P until you see oscillations, then lower it”. Plus some thoughts about I and very vague advices about D and that is all. When I got into the hobby, I’ve read all of those tutorials. And I did know more about PID…
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PPM output on FrSky X4R and X4R-SB receivers
FrSky sells 2 small Taranis compatible receivers: X4R and X4RSB. By default, they offer only PWM signal. 4 channels on X4R and 3 channels plus S.Bus (16 channels over S.Bus) on X4RSB. And that is problematic. Many flight controllers does not support S.Bus very well (no inverters) or just does not offer enough UART ports.…
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Multiple flight modes for Cleanflight with Taranis
FrSky X9D Plus Taranis or cheaper FrSky Taranis Q X7 or even more expensive X10S Horus, are incredible radios. But also can be intimidation when migrating from simpler radios. A great example is mixing multiple switches into 1 channel to pass flight mode to the flight controller. Yes, you can do it, but it can…
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What is PID controller?
Multicopter is an unstable machine. It requires constant corrections to keep is stable in the air. This is done with PID control loop. When quadcopter does not fly like you hoped, you will hear: “Tune your PIDs“. Nice. But what exactly is PID? If you did not studied control theory, and you do not want…
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Raspberry Pi + MOSFET = High power switch
With all the possibilities, Raspberry Pi requires additional hardware to turn on and off any additional hardware. GPIOs built in power limit is low: 3.3V, 16mA per GPIO, but not more that 50mA total). And while it might be enough to light a small LED, it is not enough for anything else. Forget about motors,…
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DIY FPV RC Plane with foam board – The RedCruiser Project
Few months ago I’ve wrote about my first handmade Depron airplane. It was cool design. Super simple, with KFm-2 airfoil, durable and easy to fly. But it had few serious flaws: That’s why, I have build a second foamboard airplane. This time with pusher propeller mounted on a tower behind wing. Wing is almost the…
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PPM signal support for FS-i6 radio
FlySky FS-i6 (or branded Turnigy TGY-i6) is a very decent 6 channel entry level RC radio system. But support for PPM (CPPM) standard is somehow not clear. I have no idea why manufacturer keeps PPM support data so well hidden. Anyway, here it is: how can I enable PPM on i6 radio system? PPM signal…
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PWM, PPM, and Serial RX explained
When speaking about radio systems for remote controlled models, multirotor, airplanes, gliders, there are some shortcuts that might be unknown for beginners. Those are: PWM, PPM, Serial RX, S.Bus. Today I will explain basic concepts behind them, and when they are used. PWM PWM, as Pulse Width Modulation, is something a standard for controlling different…