There are very few online resources about this PC. It is a rebranded Amstrad 3386. It is famous for a proprietary design of the keyboard, which can’t be replaced with anything commonly available. Without a keyboard, the PC will not boot.
ISA Interposer Card
This is not the keyboard that originally came with this PC. It is an Amstrad PC2386 keyboard, which is compatible with 3386 systems. Please check out the Amstrad 2386 Keyboard page where the keyboard is described in details, including the communication protocol it uses.