Convert/Connect BAFANG Torque pedal assist 32 pulses 6 wires to 12 pulses 3 wires for brushless controllers ?

BTMN

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(Well, to sumarize this post, how do I connect a BAFANG BB Torque Sensor 6 pin to a Aliexpress S866 brushless controller wich have 3pins to connect a PAS? , and I explain how I did it to try it and the problems I encountered :geek:)
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Hello people! I am completely new to eBikes and I have been searching for hours to find a solution, but to no avail. Therefore, I am reaching out for your valuable help with my problem. I am having an issue with connecting a pedal assist (PAS) to my controller. Some time ago, I attempted to "build" my own eBike using parts I had acquired, and eventually purchased a brushless controller on AliExpress for eBikes, as they are known to be compatible with a variety of eBike components. However, I want to install a pedaling assistance system instead of a throttle to comply with the laws in my country. I managed to obtain a BAFANG bottom bracket torque sensor, which I planned to install on my eBike project. The problem I encountered is that the torque sensor seems to send a positive signal instead of a negative one, and it has around 32 pulses, whereas the controller only accepts a maximum of 12 pulses. I observed the pulses by soldering a LED diode between the green signal cable and the black one to better understand the mechanism. Additionally, the torque sensor has 6 pins, while the controller only accepts 3 cables. I connected the orange (positive 5 V), black (negative GNF), and green (CAN High) cables, leaving out the white (CAN Low), brown (speed signal 1), and purple (speed signal 2) cables. I am not sure of the purpose of the last two cables, but they are labeled in the manual. My question is whether anyone has a solution to this compatibility issue so that I can successfully connect it to my controller.I've searched everywhere on the internet but nothing :/ . I've already tested whether the motor works in walk mode.The option might be to buy one on amazon but in the circumstances I'm in I can't apply it (and sorry for the bad english).

Here's the link to the controller and some videos/photos if you want to check it up:

My brushless controller link



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Ik that this is a lot more complicated than simply buying a new PAS, but it's the only solution I've got right now...😵
 

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  • BAFANG WIRING.png
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You won’t be able to use the torque sensing since your controller doesn’t support it, but you might be able to use the cadence signal on pin 3 along with the 5V and ground to work with the controllers cadence PAS input.
 
You won’t be able to use the torque sensing since your controller doesn’t support it, but you might be able to use the cadence signal on pin 3 along with the 5V and ground to work with the controllers cadence PAS input.
Oh okayy, so would you advise me to replace the green wire that is soldered to my controller's blue wire with the brown wire instead? But even if there are too many poles of magnet, the controller should activate the motor due to the pulses... or not ? Because, from watching the video, there are indeed stable enough pulses to make the motor turn. And it seems that the torque sensor sends a positive signal while my controller only accepts a negative signal, is this what is preventing the motor from turning? I know there are some technique to convert the positive signal into a negative with an NPN transistor. But well, furthermore, I don't really care about the other functions, if I can use them great, but if not, I just want to get it working correctly on my e-bike project (sorry, im a bit lost x)). If that can help you, i attach the manual that I found on the torque sensor, I'm not sure if it's exactly these models but they are very similar:

 
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