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Disassembly of UDI R/C U818A quadcopter drone

One of the quadcopters I have that was given to me as a gift several years ago is a toy quadcopter, easily found on eBay and Amazon for prices of less than $50.

It's a quite underpowered quadcopter, equipped with a camera that shoots 480p video and no audio and powered by a 2.59 Wh battery, which is rated at 3.7V with a 700mAh capacity. The entirety of the drone is plastic and the interior board is comprised of a single board, and after disassembling my own drone I discovered that there were disassembly guides already available on the internet. Not to be deterred, I have shared my own findings here on my own website as well as on my YouTube channel. These posts coincide with my YouTube videos, but my posts are sometimes more or less technical and are always written after the YouTube video is created, so there may be corrected information that I might have gotten wrong in the video.

There's a YouTube video linked above. If you're unable to see it, you can click this link to watch it in YouTube.

The singular circuit board has six dual-pin connectors which are for LED lights and can be individually controlled on one side, and four dual pin connectors on the other side, each connected to a motor. I'm not sure if the motors can be independently controlled, but I would assume logically so. There is one connector on the bottom of the board that is 4-pin, and it controls the camera. It's safe to assume two are for power and two are for signal.

A picture of what the circuit board looks like.

After scraping away some of what appears to either be hardened flux or hot glue on the circuit board, I'm able to read part of what the smaller microchip is labeled with:
...and then some more numbers and letters that is partially covered, but seem to say 03C060 or something similar.

A photo of the smaller microchip on the circuit board.

A quick Google search of the second line reveals a website in English that contains PDFs of user manuals and datasheets. I can't read what the larger microchip is labeled with, even after cleaning off hot glue, so we'll take a closer look at this one.

The MPU-6050 (appears to not be MPU-50600) appears to be a six-axis motion tracking device, which is quite strange since this quadcopter does not have features such as altitude holding, home lock, or such features that are present in more expensive "toy" quadcopters, like the Dobby. I originally suspected it to be a FC with 6DOF since the website says "6-axis," but on closer inspection it appears I'm actually quite wrong.

It looks like this board was created and has never been revised according to the documents linked on their website, so anything I'm able to achieve (in the future) could also be done to any other model of this quadcopter, unless the chipset is changed. According to the website, it's simply a 3-axis accelerator and a 3-axis compass, both of which I don't understand the need for in a quadcopter missing so many features. It's quite possible they build multiples of the same drone and simply lock out features unless you pay more money, and I do believe I have the cheapest model of the U818 that UDI makes.

According to the datasheet, there's actually been several revisions between 2010 and 2013, so I may be wrong about my claim in the previous paragraph. In addition, there's a table that lists 27 pins, but I'm only able to count 24 pins. 9 of those pins lead nowhere according to the table, but the datasheet says otherwise: 8 of them are not connected at all, and 2 are ground, leaving us with 14 pins that we might be able to trace either power or signals.

A screenshot of the datasheet, detailing what the chip does.
The chip uses I²C, which is a good thing because if it was SPI I would have a big enough headache from having so many more pins (ok maybe it's not that many more) that I might just quit right now. We'll take a look at those on a future post.

For now, you can click the link near the top of this post to watch my disassembly of the UDI U818A quadcopter and see how things are connected in the drone! Until next time,

Gideon Tong