Making it better is easy ...

A project log for Open esk8 Remote - v1

Fully open source remote control for common electric skateboards using the NRF24L01+

Timo BirnscheinTimo Birnschein 11/14/2018 at 03:280 Comments

... if it's so bad it can't get any worst.

Two days after I got my skateboard, I needed to take it apart.

Looking around the electronics bay revealed a nicely packaged battery of unknown brand in the center as well as two identical motor control boards with no visible receiver module anywhere. Long story short, the motor controllers are a noname component straight out of China with adjusted settings to meet the requests of the skateboard manufacturer. Up until now, I still have no idea who manufactures and maintains these boards but they are literally everywhere even though they are being pushed off the market by newer, more capable and more configurable boards with superior remotes. No surprise.

I took a large number of pictures, specifically chips on all boards and connections going to and from each board, motor, light and antenna: Turns out, the receiver is part of the motor controller and embedded into the circuit. To make things a bit more interesting, two boards can be configured in a master / slave setup by simply removing the receiver off of one of the boards and connecting a multi-pin cable in between the boards.

My search through the selection of used ICs turned out to be almost completely useless as none of these chips have any information online AT ALL. I even asked a Chinese friend of mine to dig around for a while and even he could only reveal the datasheet of one of the ICs - but not the important ones. 

One chip, though, was known to me: The NRF24L01+. A transceiver IC for 2.4Ghz ultra low power communication with up to 2mbit per second. This was good news, as the datasheet for it was very easy to find and comprehensive. Some say, it's not the easiest chip to work with from a protocol point of view, and I did realize, it has it's hiccups.

A second chip I could identify was located on an add on board on top of the motor controller. A board, none of the other Chinese skateboards has. Since it had the Acton logo on it, it must have been custom. It's the Bluetooth chip on a module CC2541 which is known to be compatible with both iOS and Android and available in large quantities - but huge warning: Most of these are counterfeit! To be bought from trusted sellers ONLY! Otherwise the module will only understand the most basic AT commands and cannot be paired with the original module. Been there, done that. I hate counterfeit parts!