All the setting are stored in the LCD. The LCD communicates with the control and downloads all the settings continuously to the controller. The controller copies those settings that are relevant. So the settings are stored in
both the LCD and the relevant ones in the controller.
This allows the user for example to set up a controller with an LCD and then remove the LCD and fit cable end plug/jumper (that shorts the red to blue & Tx to RX) so that controller can work without LCD.(e.g some cyclotricity kits)
The potential problem is then, if you set up a controller with an LCD and then change the LCD, the new LCD will communicate with controller with the new P & C settings which would probably alter the settings stored in the controller. However, since the 880 has less settings (& possibly different protocol?), the controller could hold the existing settings.
That is my interpretation. But you never know as the controllers have slight differences in firmware for different suppliers/applications, so you could try it if you really need to. Hopefully it would not lock up or brick the controller.
Both the LCD3 and the KT controller have been hacked on ES and a discussion along with a txt file of LCD protocols are available below.
https://endless-sphere.com/forums/viewtopic.php?f=2&t=73471
