Hello everyone.
Recently, a tool called Bubbless that emulates a bubble memory cartridge was released in Japan, but this was made for living PCBs, so this provides "only" a backup function. Therefore I'm planning to build an open bubble memory cartridge emulator that can revive all deads. (This is my first FPGA project, and all dumps, sources, schematics will be available on online.)
I've figured out how data is exchanged between the cartridge and the custom controller on bubble system PCB. To start with its storage, the bubble memory, Konami used two 1Mb bubble memories(FBM54DB) to record odd bits and even bits of whole data. Coil drivers and sense amplifiers are used for each memory and low level control signals are generated by the timing function generator MB14506. Its datasheet doesn't come out even if you browse the entire Internet, but we can assume that its feature will be very similar to SN74LS391 from TI, fuction driver from National Semiconductor, or current pulse generator from Intel.
The timing function generator receives several high level control signals from the custom controller(ASIC) and sends timing-driven signals to chip set to operate a generator, an annihilator, and array of transfer gates in the bubble memory properly at appropriate timing so that the data can flow smoothly through the sense amplifier. Since a bubble memory has only one serial data output line, the cartridge sends two 1-bit lines(odd bits and even bits) of data, page by page, to its controller. Size of primitive data in each page is >=128 bytes and bad bits must be masked out to build a set of valid data.
Anyway, I don't have a PCB now, so I must buy one to resume my project. I wonder if anyone is interested in this project.
Thanks a lot!
Plus, I found a good way to fix a dump from a broken bubble memory cartridge. Now we can derive a good ROM file.
Recently, a tool called Bubbless that emulates a bubble memory cartridge was released in Japan, but this was made for living PCBs, so this provides "only" a backup function. Therefore I'm planning to build an open bubble memory cartridge emulator that can revive all deads. (This is my first FPGA project, and all dumps, sources, schematics will be available on online.)
I've figured out how data is exchanged between the cartridge and the custom controller on bubble system PCB. To start with its storage, the bubble memory, Konami used two 1Mb bubble memories(FBM54DB) to record odd bits and even bits of whole data. Coil drivers and sense amplifiers are used for each memory and low level control signals are generated by the timing function generator MB14506. Its datasheet doesn't come out even if you browse the entire Internet, but we can assume that its feature will be very similar to SN74LS391 from TI, fuction driver from National Semiconductor, or current pulse generator from Intel.
The timing function generator receives several high level control signals from the custom controller(ASIC) and sends timing-driven signals to chip set to operate a generator, an annihilator, and array of transfer gates in the bubble memory properly at appropriate timing so that the data can flow smoothly through the sense amplifier. Since a bubble memory has only one serial data output line, the cartridge sends two 1-bit lines(odd bits and even bits) of data, page by page, to its controller. Size of primitive data in each page is >=128 bytes and bad bits must be masked out to build a set of valid data.
Anyway, I don't have a PCB now, so I must buy one to resume my project. I wonder if anyone is interested in this project.
Thanks a lot!
Plus, I found a good way to fix a dump from a broken bubble memory cartridge. Now we can derive a good ROM file.
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