The vision comes to life!

After many weeks of mechanical design, I emerge with a 3D printable enclosure for the future C256 Foenix.

Along the way, I lay out my preliminary block diagram with its different components. The final specs are far from being defined, but the big blocks are decided upon.

I know by then that there will be 3 custom chips (FPGA) in the C256, VICKY (the video/graphic) chip, BEATRIX (the sound and Interrupt Controller) chip and finally GAVIN, for the I/Os, DMA Controller and system controller. Finally, the whole system will be driven by a 65C816@14Mhz, the fastest speed I can get out of that part that I will be able to buy off the shelf.

Also, I decide that the system will have a total of 2Meg of RAM. A permanent 512KBytes for the Code and Data. I am not counting the ROM (EPROM) that will be in the system for the Kernal & BASIC & Characters. There will be an empty socket for future expansion for another 512K and then a permanent 1MByte for VICKY, for the bit map/sprites/etc. I also set the standard resolution for the graphic to 640x480@256 Colors from a 24Bits palette look-up table.

These are the choices I make early on about the system. I realize quickly that it could be very easy to just use a soft core of the C6502 in a FPGA and drive it at an insane speed as well as using a lot more memory than just few Megs, but I refuse to go towards that route, instead I insist to follow this set of rules:

- Try to design it, like it is 1987 with the I/O available at the time, with a minimum of parts that are very actual. (FPGA will be an exception since, they could be considered and will be considered like a Custom chip designed by the CBM semi-conductor group. In the end, they will be treated as such.

- The C256 Foenix will have to have the same kind of feel and user experience as its predecessor. Like the Commodore Basic, Border screen, same character FONT, etc...

- Limit myself in terms of memory size. Memory is cheap these days and putting too much will be like to not put enough.

- Limit myself with the graphic modes and color. Flexibility is the key here... I believe that limitation is the mother of creativity.

Finally, here something I have considered but decided NOT to do:

- I could possibly have used either the C64 or Amiga new molded enclosure that some have been through some kick starter to recommission. I am not going that route for 2 reasons, first the enclosure are pretty expensive and then, there are the keyboards that would have to go along. I saw some people redesigning the keyboard as well, but still they are fairly expensive considering that they are sold as replacement part and not high volume for production. On the the other hand, I have made the choice to put a Header connector a 6521 CIO just in case somebody would like to design their own case with an old keyboard.

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More to come!!!