build.prop file I found an entry commented "Enable USB BICR function" (
ro.sys.usb.bicr). I searched in Internet, but I did not find anything useful. Maybe you know?
I found some hints in the MediaTek (MTK) kernel sources.
There is no description but with a bit of guessing it seems that this option allows you to present a virtual USB CD-ROM when connected via USB to a PC. Often this is used for providing specific drivers that are required for accessing special functionality of the device. The virtual CD is present on the Android device in form of a ISO-image.
From my understanding this option is only relevant for developers creating a custom ROM.