Here's a run down of the initial CUBE Eurocard range:
CUBIT a 6502 based microprocessor Eurocard, was supplied with CUBOS a disk operating system which could support Acorn Atom Basic or BBC Basic
CUBIT was interchangeable with:
CUMOT a Motorola 6805 based microprocessor Eurocard
and
CUNINE a 6809 based microprocessor Eurocard intended to run the FLEX operating system
CU-GRAPH an 80x25characters video card available as -mono a (16K) black and white version supplied with systems 10 and 20 or -extension a (48K) colour version supplied with the systems 15 and 25
CU-DRAM a memory expansion card which could hold up to 64K of Dynamic RAM
CU-PRINT a printer interface card (supplied with systems 10 and 20, not required with systems 15 and 25 as a printer interface was provided on the graphics card ?)
CU-KEY the CUBE QWERTY keyboard
CUBAN provided 8-bit and later 12-bit analogue-to-digital and digital-to-analogue conversion
CUMEM a universal memory carrier, can accept up to 16K of battery backed up RAM or 64K of ROM/EPROM
CUBIO accepts up to four parallel interface chips providing up to 80 digital I/O lines
CU Backplanes a wide range of sizes of backplane were available