Commander X16

Just now, James Anders Banks said:

Is there a typo there, should say "than the X16p"? Or have I really badly misunderstood this time?



Again thanks for the detailed reply.

Typo, thanks for the catch.

On 8/20/2021 at 4:31 PM, rje said:

 



I can.  If it's easier to use the VERA on the X8, then maybe I'd rather program on that instead of the X16.



The hobby platform has to be hackable, but (in my case) accessible too.



 

Developers hat on, I’d rather the x8 design, period. The pipe is an understandable design decision but makes too much too challenging. Michael and I wrote line routines independently and they’re about the same speed. I don’t think anything that doesn’t fit sprites and tiles really works.

On 8/20/2021 at 5:49 PM, Scott Robison said:

As for the whole X8 vs X16. It would be ideal if X8 had the same interface to VERA as X16 has, but I don't think that's a show stopper. I've not seen it, but 38 years of programming experience leads me to believe a couple kernal routines can paper over the difference between accessing the two interfaces, or a couple routines in the program if not available in the kernal, or even conditional compilation and assembly for maximum speed.

Yes and no.  I think the X8 would be able to do things the X16 can't. You can work round the sprites and tiles stuff, the setup and data copy. Where you have a problem is mimicking the direct access you have to the X8 ; the window allows you to do things that the X16 just can't do quickly enough. If you wanted to rewrite Elite for example you could probably fill polygons, whereas on the X16 you'd have a problem drawing lines quickly enough.

On 8/20/2021 at 6:27 PM, x16tial said:

In the end, I think David needs to revisit his former self: the one that imagined the "Dream Computer".



Is the X8 that computer?  I think he's indicated that it isn't; not quite. It's pretty neat, but is it the Dream?



I think the X16 full version, was, and still is, that dream computer.  If so, that should be the focus, everything else is distraction, and when you don't have unlimited time and money, distractions are killers.  And it seems they can be even if you do.



David will have to decide if I'm wrong, but focus is needed.  What would "Dream Computer" David have wanted at this moment?

Actually the X8 is way closer. The original plan was something that was going to cost $30. I don't think that's doable, maybe as a DIY kit just, but there's a thing called the ZX-Uno which is effectively a Superspectrum, which is something like $60-$80 to produce I think. You could probably design it for less now.

The "real hardware" design came later.

On 8/20/2021 at 8:06 PM, Carl Gundel said:

I have no interest in the X8.  Please convince me.

It's cheap, technically feasible and nearly the same thing. I don't know if it has external RAM or uses Block RAM, but effectively what it does is move the 6502 into the FPGA rather than existing as a seperate chip.

It's already too many black boxes. Aside from obviously Vera which now does most of the sound and all the graphics, there are microcontrollers and all sorts to make it work.  It's a black box already. If you want the bells and whistles do Ben Eater's course. If you want to build a kit, it could probably be a kit.

I think it's a no-brainer personally. Largely because if nothing happens soon the project will die.

On 8/22/2021 at 1:18 AM, TomXP411 said:

So as a BASIC computer, the C8 is actually a better machine. As a machine language or C computer, the X16 has some benefits... but I'm starting to think those benefits aren't as worthwhile as folks think. The real advantage of the X16 is the expansion and User ports, not so much the expanded RAM.

Hardware's not my thing, but couldn't you just have an I2C port on the FPGA for expansion ? Then if you wanted (say) a classical user port you could get an Arduino to do it, maybe.

On 8/23/2021 at 9:53 AM, Shauny said:

The X16 turned out to be an odd abomination, with it's mix of fpga and old ICs, certainly not a computer built from off the shelf parts originally envisaged. The X8 is not what was originally envisaged either, it's just fpga, a poor relation to the likes of the Mega 65 or the Sinclair Next and the Raspberry Pi4. 



What's worse is it could be seen as a poor attempt to clone the C64 mini.



 

The Next and the M65 are pretty much entirely FPGA, they just have external RAM (which may be worth considering for the X8 ? Thinking of Grant Searle's work here). You can have a working M65 now, you just need a Nexys A7 board.

On 8/23/2021 at 7:50 PM, Scott Robison said:

I'm willing to give it a try, but I suspect I would make three.

Four. Though I did manage the Gigatron ?

On 8/24/2021 at 4:04 AM, TomXP411 said:

Yeah, I'm kind of wishing they had gone with the open ROMs and used a FOSS 6502 BASIC. There are a couple out there. 



Or if there isn't a suitable one, the community could probably have built an interpreter by now. Add the text editor and assembly environment written by other folks here on the forum, and we'd already be done with the firmware - without paying Cloanto a red cent. 



 



 

It's probably easier than trying to fudge MS Basic, especially for long identifiers and similar. Still if the description of the X8 is correct and it's a small boot ROM, then replacing it is trivial-ish.

On 8/24/2021 at 5:06 AM, BruceMcF said:

But that's spilled milk under the bridge ... or some such ... and with a commitment that it will be possible (but at User Risk) to flash a CX16p board, if the intersection of people interested in having a FOSS alternative BIOS and Basic, people with required range of 6502 assembly language and other development skills, and people with the time to commit to the effort is not an empty set, that project could be forked today.



I would not actually be surprised if it happens someday, but I wouldn't expect it to happen until the boards are released.

Already exists https://github.com/paulscottrobson/6502-basic

No floats , largely because I don't like them ? but the hooks are all in there for it. It's designed to run in banked RAM, but doesn't have to. Haven't worked on it much recently. Whole pile of graphics sprite and sound functions, and a 65C02 assembler. From memory it's about 14k or something. https://github.com/paulscottrobson/6502-basic/blob/main/documents/Reference.pdf