I had goosebumps reading it. I will have to read again and again... Amazing!
Virtualizing the 6502 on a 6502 with 6o6
11–20 of 32 posts
Re: Virtualizing the 6502 on a 6502 with 6o6
#12> Here's the first of my bucket list projects I'm completing which I've intermittently worked on for literally two decades.
This one hell of a bucket list you must have. Respect.
Re: Virtualizing the 6502 on a 6502 with 6o6
#13Despite how simple and limited the 6502 is, it's always interesting to see this almost 50-year-old architecture being stretched to new limits. 6502 cores are still found in some SoCs aimed at the ultra-low-cost high-volume market.
> 6502 cores are still found in some SoCs aimed at the ultra-low-cost high-volume market. What's the reason behind that? Probably just keeping existing, working designs and thus saving R&D costs? Sounds like beating a 10 cent risc-v core would be hard. Edit: When I first read your comment I had to chuckle a bit, because I got the image of a multicore SoC with 6502 6502 cores. That would be a fun project for my FPGA h…
10c per part is incredibly high depending on how low-cost we're talking.
If your chip needs very basic processing, and you're going to sell it for less than a cent per chip, you need your core to be basically free.
Sure RISC-V is very inexpensive, but for parts like these risc is massive overkill and as a modern core, you'll be spending a lot of die area on a core that should really be an ASIC, but designing an ASIC is expensive so you can just slap a 6502 in that bad boy and call it a day.
On the other end of the scale, you'd be surprised to learn that many chips you don't ever interface with as a user contain even ARM cores. These are usually ASICs in high-end products.
Re: Virtualizing the 6502 on a 6502 with 6o6
#14Earlier quoted context omitted.
> 6502 cores are still found in some SoCs aimed at the ultra-low-cost high-volume market. What's the reason behind that? Probably just keeping existing, working designs and thus saving R&D costs? Sounds like beating a 10 cent risc-v core would be hard. Edit: When I first read your comment I had to chuckle a bit, because I got the image of a multicore SoC with 6502 6502 cores. That would be a fun project for my FPGA h…
10c per part is incredibly high depending on how low-cost we're talking. If your chip needs very basic processing, and you're going to sell it for less than a cent per chip, you need your core to be basically free. Sure RISC-V is very inexpensive, but for parts like these risc is massive overkill and as a modern core, you'll be spending a lot of die area on a core that should really be an ASIC, but designing an ASIC…
Go on!
Re: Virtualizing the 6502 on a 6502 with 6o6
#15Earlier quoted context omitted.
> 6502 cores are still found in some SoCs aimed at the ultra-low-cost high-volume market. What's the reason behind that? Probably just keeping existing, working designs and thus saving R&D costs? Sounds like beating a 10 cent risc-v core would be hard. Edit: When I first read your comment I had to chuckle a bit, because I got the image of a multicore SoC with 6502 6502 cores. That would be a fun project for my FPGA h…
10c per part is incredibly high depending on how low-cost we're talking. If your chip needs very basic processing, and you're going to sell it for less than a cent per chip, you need your core to be basically free. Sure RISC-V is very inexpensive, but for parts like these risc is massive overkill and as a modern core, you'll be spending a lot of die area on a core that should really be an ASIC, but designing an ASIC…
>but for parts like these risc is massive overkill
You seem to underestimate how small a RISC-V core can be.
Take a look at SERV.
Re: Virtualizing the 6502 on a 6502 with 6o6
#16Despite how simple and limited the 6502 is, it's always interesting to see this almost 50-year-old architecture being stretched to new limits. 6502 cores are still found in some SoCs aimed at the ultra-low-cost high-volume market.
> 6502 cores are still found in some SoCs aimed at the ultra-low-cost high-volume market. What's the reason behind that? Probably just keeping existing, working designs and thus saving R&D costs? Sounds like beating a 10 cent risc-v core would be hard. Edit: When I first read your comment I had to chuckle a bit, because I got the image of a multicore SoC with 6502 6502 cores. That would be a fun project for my FPGA h…
[deleted]
Re: Virtualizing the 6502 on a 6502 with 6o6
#17This post has been hanging out with no comments for ages. I was like, I'll skim it later. > It's almost burying the lede to announce that, though, because the real meat in this entry is how the Commodore 64 manages to emulate a very different 6502-based system. That piece is "6o6," for "6502-on-6502," and is a full virtualized software NMOS 6502 CPU that runs on a 6502 CPU — which I've open-sourced too. It has full c…
> Also, it reminded me of this "The Zilog Z80 has a Protected Mode" https://www.youtube.com/watch?v=DLSUAVPKeYk posted to hn, but got no discussion.
Here is a thread with 138 comments: https://news.ycombinator.com/item?id=33229526
Re: Virtualizing the 6502 on a 6502 with 6o6
#18Despite how simple and limited the 6502 is, it's always interesting to see this almost 50-year-old architecture being stretched to new limits. 6502 cores are still found in some SoCs aimed at the ultra-low-cost high-volume market.
> 6502 cores are still found in some SoCs aimed at the ultra-low-cost high-volume market. What's the reason behind that? Probably just keeping existing, working designs and thus saving R&D costs? Sounds like beating a 10 cent risc-v core would be hard. Edit: When I first read your comment I had to chuckle a bit, because I got the image of a multicore SoC with 6502 6502 cores. That would be a fun project for my FPGA h…
A lot of cheap USB1/2 widgets are actually a 6800 core. It's crazy how these old CPUs have stuck around for so long
Re: Virtualizing the 6502 on a 6502 with 6o6
#19This is amazing. It brings back memories of the first time I taught myself 6502 assembly, there was a book called “The Visual Computer” that came with an emulator on a floppy disk. It was very eye opening! I found a PDF of the book [1] but not sure if the software on the floppy survives anywhere.
[1] https://files.commodore.software/reference-material/books/c6...
Re: Virtualizing the 6502 on a 6502 with 6o6
#20Earlier quoted context omitted.
10c per part is incredibly high depending on how low-cost we're talking. If your chip needs very basic processing, and you're going to sell it for less than a cent per chip, you need your core to be basically free. Sure RISC-V is very inexpensive, but for parts like these risc is massive overkill and as a modern core, you'll be spending a lot of die area on a core that should really be an ASIC, but designing an ASIC…
>but for parts like these risc is massive overkill You seem to underestimate how small a RISC-V core can be. Take a look at SERV.
There’s also the cost of rewriting (yes, from assembler) all the existing code. And don’t forget QA.