My bubble memory emulator project was completed successfully. It reads data from an onboard SPI flash and sends data to the controller in bubble memory protocol. Core modules consume ~450 LEs of an Altera Cyclone IV. I think this is quite light.
Since the data structure of a bubble memory is at the discretion of a developer, it is also incompatible with the current or the future release of MAME. Furthermore, special data that does not exist in an existing release must be supplied for complete emulation.
