I’ve been involved since 1983, and follow all the time the development of the C64 in the form of emulation, as well as FPGA. But I haven’t seen my dream yet: A Micro C64, a chip that combines all other chips of the C64, the whole hardware infrastructure on only one power saving silicon die, so the chips: 6510, PLA, 6526, RAM, ROMs (Kernel, Basic, Batches), VIC II, SID 6581, …
And in the following way:
The chip is clocked with 1-8 Mhz. Kernel, Basic and Chargen Roms are “empty” at the moment of switching on. These are automatically filled from the outside via a micro SD card after switching on. All necessary connections are led from the chip to the outside: HDMI Out, serial, user, expansion, tape, joystick ports. By default, the Micro SD card is registered as 1541 Device 8, with a folder named “1541”. The tape is represented on the micro SD card by the folder “Tape”.
In the end you have a “real” C64 and no simulated C64, which is maximum flexible. If old C64 games are loaded, the system automatically switches down to 1 Mhz. The main problem with the new C64 Reloaded MK2 Board and the FPGA Ultimate64 Board is: the big size. They are huge! There is no Real Micro C64.
In addition, memory injection should be possible (for this is a value necessary that is send outside to the external environment, that represent the rasterline state, PC and Flags were also good), so that you can make more out of the “real C64” environment. That is, to make it “indirectly” networkable from the outside, as I do with my AC64Lib and the C64 emulator “C64 – A Legend”. Then you can run the real C64 system with only 1 Mhz, because the rest is done from outside (injected: Sprites, Bitmap, …).
Instead of the 1- Chip Die you could also build a Micro C64 in “Stacked” form (2 boards on top of each other), so minimum dimensions. I will plan this “Stacked” C64 soon and try to realize it.
The biggest problem at this time is a not existent VIC II Pin Adapter -> HDMI, without the Video and RF circuit. For now I will use an internal VIC II Pin Adapter -> Video and then an external Video to HDMI Converter.