Commander X16

Hello Commandos,

As you know the Mega 65 is another great project and based on Commodore's never-released C65 computer. Obviously the hardware is a bit different as it is FPGA-based, but I was curious, what do you prefer about the Commander X16 (chips aside) and its specifications and software, over the Mega 65's OS (if anything). What drew you here?

Your friend in retro, Perifractic

I'm not sure if I actually care if it's an FPGA. Functional equivalent doesn't bother me. It doesn't bother me AT ALL to use an SD2IEC card on my Commodores. Sure I have a 1541, but the SD card is more reliable.

I ordered a Mega 65 so I'll know more about how I feel about it when I get it.

I'm very curious how things like this will be received without at least some of the community driving the nostalgia factor. I use my C64 and 128 all the time at least in part because there's some nostalgia for it. But I skipped over the Amiga in my computer journey in the 90s. Went to DOS and then Linux in 1996.  I own an Amiga 600 and don't use it because it doesn't resonate with me like a C64 does.

Should be a fascinating thing to study really.

Graphically they aren't too far apart, in terms of the tile maps and so on. This isn't surprising as they are both developments of C64/C65. The Mega65 is probably more powerful but a bit messier and confusing. The X16 is relatively simple, you can figure it out mostly straight off (this isn't a criticism). The Mega65 does not have the CX16's problem of the limiting bridge between the processor and the graphic memory. The CX16 has more sprites but less options for replacing them in other ways.

There is one huge difference. (And yes I do know why, authenticity). The 6502 in the Mega65 has several changes. One is to widen the address bus so it can access 24 bit addresses (though it is still basically a 6502). Another is the addition of some 32 bit data operations. The last is the clock speed ; it runs at 48Mhz (not sure but about this but it's this sort of order). This is fast enough to put it in the same box as the ARM system David reviewed a while back ; you can write proper retro style games without having to write in Assembler, and you can run a fast enough P-Code system. Having done it on my own system I've a pretty good idea how much "poke" you need to make it work, and the CX16 doesn't quite have it (by a factor of 2-3) without big chunks of assembler. It doesn't bother me writing it, but it handicaps the beginners. The more the merrier though, why not Robotron in BASIC.

Both have similar systems software, basically bodging the C64/C65 kernel and BASIC ROM to provide limited support for the extended facilities and interface to SDCards rather than cassette tape. Sound is much of a muchness. For some reason there's a floppy on the prototype (can you buy them any more ?)

The other difference is that the M65 has a huge software base, though to be honest this doesn't really matter. If you just want to play Game X on the C64, you can either buy that Mini64 gadget, or simply run it on VICE or similar. It's easier and simpler. If you want to play a game, you want to play a game. Backwards compatibility is nice but overrated IMO, applies to the Spectrum Next as well.

They aren't really that different. The last time I looked, the FPGA was doing all the graphics, the PCM, at least some of the audio channels and the SDCard I/O. This leaves you with the CPU, RAM and ROM (which are external on the M65 I think), possibly some audio channels, and a PIA/VIA for interfacing (the keyboard port may be on the FPGA now, I'm not sure).

So basically the difference is that the M65 has a CPU in the FPGA and the CX16 doesn't.

And the prototype M65 batch is 1000 Euros. Not sure what CX16 is going tobe, other than way more than Dave's £ 30-40 estimate.

1 hour ago, Fenner Machine said:

There have been and are many retro/hobby/oldskool new 8/16-bit style systems in development.

They all have pros and cons.

I have one myself as have countless others. It's faster than the CX16 and costs a tenner. But there is one important pro that none of the others have, except for three ; a large potential user base - the three are the Spectrum Next, the Mega 65, and the Commander X16. (there are others that have smaller bases, the Gigatron, RC2014, Zx Uno perhaps and so on).

Without that user base you don't have software, an eco system, and without that you have another in the long list of machines that were technically excellent but you couldn't do much with. In the 1980s when I was a lad there were many of them. Neither the Speccy or the C64 is a particularly good design, the aim being to maximise profit for minimum design effort. But there were so many of them people worked round their limitations to often spectacular results. In some ways it's an advantage. Without the option of flashy graphics or sound on a Spectrum, people tried new game ideas instead.

The c65 has some design decisions i really don't like:

Built in floppy drive --> Those drives already sucked in the 80s and they still do today. Unreliable, slow and noisy. Case is bulkier and the machine becomes more expensive. But hey, it's the nostalgic touch that counts, isn't it?

Minor design flaws (e.g. the chosen battery for the RTC. Would be an easy fix, but the c65 is a very academic project approach ...)

And both designs do not offer a simple way to use modern peripherals (except the keyboard on the x16, which i really dig), e.g. USB devices, Bluetooth, Wifi, ...

And thus i chose the Mister instead of both, maybe the cores of the x16 and c65 get ported some day. The Mister is obviously done by very grounded and experienced people and that shows in hard- and software-design.

But the x16 community is great and the barebone approach has really a very nice touch. So i'd prefer the x16 over the c65 :-).

 

I think it's fair to enjoy both systems for what they bring to the table. I'm interested in both computers, and I feel the Commander will be more of an experimenter's tool, where the MEGA will end up being primarily a modern Commodore 64 replacement.

The FPGA doesn't bother me one bit. In fact, I think the Ultimate 64 has proven that an FPGA system can be highly compatible and still superior to the original. Gideon's $240 motherboard is both faster and more powerful than anything ever made for the C64 with discrete components: The 48MHz CPU alone is a first for Commodore 8-bit computers, for example.

So both have their place, and I'm more interested in seeing how both fit into the scene than in picking a side. 

 

 

The X16 also appeals to my desire to experience some of that 8-bit era of programming, through the rose-tinted glasses of modern programming environments and tools.

Personally, I've looked at a lot of the other 8-bit projects, whether based on real platforms or not, as having a high possibility of being vaporware, or else being a cash-in from the IP owners.

I don't fault the cash-ins for what they are; my nostalgia simply runs in along different veins. I'd rather see cash-ins than abandonment, and the historical preservation factor is no small part of that.

But the X16 has the "Dave factor", which to me brings two important qualities to make me interested:

• 
  Dave has shipped products before.
  


• 
  Dave has an audience and community he can easily promote his project with, which may not exist to the same extent for other 8-bit projects.
  

I happen to also appreciate the goal of implementing the system entirely without FPGAs (albeit with asterisks since certain hardware is no longer available), this makes it feel more authentically 8-bit to me, since it's not emulated magic. I actually somewhat hope there will be some hardware quirks discovered post-launch, as long as they aren't too annoying. :3

For me the X16 appealed more for the following reasons:

1. 
   You will be able to look at the board and kind of "see" how it works. I love that!
   


2. 
   Memory layout and bank switching is very basic, but also easy to understand. The amount of available memory imposes pressure to optimize. I like that!
   


3. 
   Graphics is somewhat in between an ATARI ST and the Commodore Amiga, so more 16-bit era like. Which allows for good 2D graphics and I'm very happy what I've achieved so far. The pixelated 320x240 resolution adds to the nostalgic feel.
   


4. 
   The 8 MHz CPU is fast compared to the C64, but still slow enough so that you have to live with certain limitations, which is part of the fun. But it still allows me to use C for programming with some assembler to get around the mentioned limitations.
   

I'm looking forward to "real" hardware. I'd like to show it to my nephews (now 3 and 6 years old) in a few years, to explain and "show" them how computers actually work. I find it still very important to know about those basics. Even with modern computers this helps to understand why certain things work and others suddenly don't.

7 minutes ago, AndyMt said:

I'm looking forward to "real" hardware. I'd like to show it to my nephews (now 3 and 6 years old) in a few years, to explain and "show" them how computers actually work. I find it still very important to know about those basics. Even with modern computers this helps to understand why certain things work and others suddenly don't.

I agree. No matter how advanced our main desktop/laptop computers become, it's not like a baby born in 2020 has Ohm's Law, Boolean Logic, and hundreds of other concepts in "factory ROM" or something. You have to start with the absolute basics. If anything, modern computers are near-overwhelming, with no single person able to build one themselves. In a way, it's better to have a much slower computer you can understand/fix than a much more powerful one that is essentially magic. But practically speaking, it's good to have both for different reasons.

For me, Dave's goal to keep the system understandable, buildable, hackable (discrete components rather than FPGA) is a big plus.