Although the new computers would be compatible with their respective originals, they are not exact replicas. And why would they be, really? The world deserves a better C64 and a better Spectrum. Such a project would also open up the possibility for further "cloning" with contemporary means, ensuring the platforms live on.
Anyway, all this made me think, what would I like to see from such a project?
Overall, the new computers could be more flexible for building different types of cases and input/output solutions. The 1980s home computers were notoriously closed products. Many connectors could be made as header pins, and the responsibility for building the less often used connectors would be up to the owner or third parties.
There are two schools of thought about the video output. Others would like a current (hdmi) video output for modern displays, whereas others see old-fashioned monitors and TVs as a must. One possibility is to have modular video output, you'd only get what you need. However it can be a bit of a space-waster really. ZXEvo has it pretty good, a VGA output and then header pins for RGB.
Given this overall idea, below are my wishlists. These are simply fantasy as I can't really plan this type of stuff.
The Fantasy models:
- Circuitboard footprint that fits in at least some Spectrum model case (preferably the toastrack 128, but maybe +2/+3)
- A new z80 processor 3,5mHz/7mHz/14mHz
- 48K-64K base RAM, Memory expansions through the 128K memory model or more as in Russian machines (Evolution).
- FPGA ULA video generation. Preferably pins for RGB and composite, but also modern hdmi.
- FPGA YM audio generation. Also a socket for real YM
- Alterable timing schemes: Russian Pentagon, British Spectrum, something new? (Not sure how to achieve this)
- SD card reader. I would maybe leave out the floppy controller.
- First 16K as re-writable/replaceable ROM, or as RAM with write protect.
- Reasonably compatible zxbus/edge connector pinout
- Keyboard input pins compatible with the original spectrum, but also USB or at least PS/2
- Audio jack/pins
- Joystick pins (sinclair/kempston)
- Kempston mouse compatible mouse port, maybe USB or at least PS/2
So, quite similar to ZX Evolution really. The major difference is trying to make it fit in smaller space and leave out certain things. I'm not too keen on new display modes, but why not.
If there has to be a new case, borrow ideas from 128K Spectrum or Sinclair QL, but a bit flatter if possible. The QL keys looked cool but I guess they have to go. The Next renders look good but in my opinion round shapes never quite belonged with the Spectrum... What I'm looking at is a keyboard-less case, that could be altered to integrate a keyboard.
- Original footprint circuit board, preferably short board
- A new 6502 processor? Does such a thing exist?
- 64K memory, expansions via the REU standard. Also REU on board, what's the maximum, 16MB?
- Standard serial port (real 1541, SD2IEC)
- SD card reader
- Cartrdige expansion as 100% cartridge-compatible as possible.
- FPGA SID. Audio generation via SID emulation, also a socket for real SID 8580/6581 or Swinsid
- FPGA VIC-II. Video generation, preferably both composite/RGB and modern hdmi
- Joystick ports/pins
- Commodore mouse compatible mouse port, maybe USB or at least PS/2
- Keyboard input pins compatible with the original C64, but also USB or at least PS/2
- Audio jack
The C64 is a tricky thing. With Spectrum, the specs are simple and there's also some precedent for ignoring them. Consider the Russian scene for example, who have very nearly redefined what a ZX Spectrum is. But with Commodore 64, fans would not be satisfied with anything less than a timing-exact, perfect, real thing.
If there's a new case, it would be C64C-style, and forget the original brown breadbox colors. Yes the breadboard is nostalgic but it's a bit too tall and ugly to be honest. With keyboards it's a different thing. Many functioning originals exist so it would be wise to allow using the genuine item. This pretty much then defines the form of the computer. Proper arrow keys would be welcome, though.