860C Controller
Seems popular with the TSDZ2 open source people. Electrify Bike has one ready with a custom(?) harness. https://www.electrifybike.com/products/complete-controller-860c-display-for-tsdz2-open-source-firmware-osf They say: The 1 To 4 main harness cable enables the use of all of the bafang throttles and brake cutoff sensors. These are all selectable below for inclusion with the upgrade kit. The harness is compatible with the KT-LCD3 display and the 850C color display. It will also work with the SW102 Bluetooth display when the firmware is complete. We are currently loading TSDZ2 OSF version v20.1C.3. Controller installation: The upgrade is a mostly straightforward and easy operation. You just take off the motor cover and the plastic cover under the chainring. Then you can see the controller and the rest is fairly obvious. The only part that is a little bit tricky is prying out the rubber plug around the cables where they pass through a hole in the motor body. Here is a video showing how