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David Murray (aka the 8-bit guy) has a plan to build the "Commander X16", a new 6502 based computer that is philosophically similar to a VIC-20 but has more RAM

David Murray (aka the 8-bit guy) has a plan to build the "Commander X16", a new 6502 based computer that is philosophically similar to a VIC-20 but has more RAM (2MB), a higher clock (probably 8 MHz) and an FPGA to do VGA video. It might not be on the radar of people here because of some odd choices, like using a Facebook group as the primary discussion forum.

kgwxd 7y ago
I really can't wait for that to happen. I'm going to be throwing money at that project like crazy. There's already an emulator for the OS [1]. I had never done any C64 programming, but I was able to do some BASIC tutorials using it with the exception of any video stuff, since that will be different on the X16. He did some videos about the project [2] [3]. I absolutely hate that he formed the group on Facebook. I'll be missing so much. [1] https://github.com/commanderx16/x16-emulator https://github.com/commanderx16/x16-emulator [2] https://www.youtube.com/watch?v=ayh0qebfD2g https://www.youtube.com/watch?v=ayh0qebfD2g [3] https://www.youtube.com/watch?v=sg-6Cjzzg8s https://www.youtube.com/watch?v=sg-6Cjzzg8s
- ddingus 7y ago
  I think he's gonna hit the sweet spot. Great project. Fan here for sure. Watching him grow his retro channel has been a lot of fun. Seems like a great guy, and he's got a sense of where retro hits home.
- bremensaki 7y ago
  He and his brother have independent forums as well, and there's a sub dedicated to the X16. https://murray2.com/forums/commander-x16.9/ https://murray2.com/forums/commander-x16.9/ It's still primarily on Facebook, unfortunately, but the forum is starting to finally gain some momentum as well. Lots of information on the project in there. Some good discussions on other retro topics too. Worth a visit.
deleted 7y ago
[deleted]
jmccorm 7y ago
His project certainly has my attention! Only two things have me concerned right now: cost (the question of if it can reach scale) and video. His current choice for a video co-processor "Vera" excites and concerns me in equal measure. At the top-end, it outputs to VGA with a 640x480 bitmap mode using an an active palette of 256 colors (out of 4096 colors) per pixel. It supports 128 sprites and interrupts (used to indicate sprite collisions, an active video line, or vsync). All that sounds great, doesn't it? The majority of what I don't like is that the video processor is essentially off of the main bus. The CPU only has access to video through a set of 8 registers (plus interrupt). So it has 128k of private video memory and an additional 16k for video registers, palette, and sprites. If I'm reading this correctly, its private video memory won't hold a full 640x480 256 color bitmap image, which would be ~300k. So it seems like you'd have to load video memory with the second half while it is drawing the first half (and vice-versa). I'm also wondering if an old-school technical like page-flipping is really going to be possible here. EDIT: Or to put it another way, because the video co-processor doesn't have enough memory to hold the entire image all at once time, and because the video co-processor cannot access main memory, just to hold a static photo-realistic image on the screen you're going to have to constantly copy ~300K of pixels from main memory into video memory... each and every frame. If I'm doing my math right, that'd be more than 36 million operations per second just to pump the data into the video co-processor? It reads to me like the co-processor isn't doing a great job of offloading work from the CPU here. All of these concerns might be dismissed simply by saying "the CPU is much faster than those other 8-bit platforms you're used to". Assuming that isn't the case, I'd probably like to see the video co-processor have enough memory to hold two full pages of bitmapped video. I'd also greatly appreciate it if they could arrange for direct CPU access through one of their pre-existing banked memory regions. Still, I'm eager to see how David's project progresses.
- colejohnson66 7y ago
  I’d assumed they’d just add more ram to the Vera chip, but I don’t know the details of if that’d be possible.
  - jmccorm 7y ago
    I'd hope so. Or they could leave it in as an old-school quirk that you have to hack around in order to get the most out of a bleeding-edge vintage home computer. I'm not sure of their intent here? There's this clip https://www.youtube.com/watch?v=sg-6Cjzzg8s&t=2082 https://www.youtube.com/watch?v=sg-6Cjzzg8s&t=2082 from his "Building my Dream Computer - Part 2". I'm kind of wondering if David understands the issue, or if he just had problems communicating it to his audience, or if I'm just plain wrong and this clip is just a coincidence?

kgwxd 7y ago

I really can't wait for that to happen. I'm going to be throwing money at that project like crazy. There's already an emulator for the OS [1]. I had never done any C64 programming, but I was able to do some BASIC tutorials using it with the exception of any video stuff, since that will be different on the X16. He did some videos about the project [2] [3]. I absolutely hate that he formed the group on Facebook. I'll be missing so much. [1] https://github.com/commanderx16/x16-emulator https://github.com/commanderx16/x16-emulator [2] https://www.youtube.com/watch?v=ayh0qebfD2g https://www.youtube.com/watch?v=ayh0qebfD2g [3] https://www.youtube.com/watch?v=sg-6Cjzzg8s https://www.youtube.com/watch?v=sg-6Cjzzg8s

ddingus 7y ago
I think he's gonna hit the sweet spot. Great project. Fan here for sure. Watching him grow his retro channel has been a lot of fun. Seems like a great guy, and he's got a sense of where retro hits home.
bremensaki 7y ago
He and his brother have independent forums as well, and there's a sub dedicated to the X16. https://murray2.com/forums/commander-x16.9/ https://murray2.com/forums/commander-x16.9/ It's still primarily on Facebook, unfortunately, but the forum is starting to finally gain some momentum as well. Lots of information on the project in there. Some good discussions on other retro topics too. Worth a visit.

deleted 7y ago

[deleted]

jmccorm 7y ago

His project certainly has my attention! Only two things have me concerned right now: cost (the question of if it can reach scale) and video. His current choice for a video co-processor "Vera" excites and concerns me in equal measure. At the top-end, it outputs to VGA with a 640x480 bitmap mode using an an active palette of 256 colors (out of 4096 colors) per pixel. It supports 128 sprites and interrupts (used to indicate sprite collisions, an active video line, or vsync). All that sounds great, doesn't it? The majority of what I don't like is that the video processor is essentially off of the main bus. The CPU only has access to video through a set of 8 registers (plus interrupt). So it has 128k of private video memory and an additional 16k for video registers, palette, and sprites. If I'm reading this correctly, its private video memory won't hold a full 640x480 256 color bitmap image, which would be ~300k. So it seems like you'd have to load video memory with the second half while it is drawing the first half (and vice-versa). I'm also wondering if an old-school technical like page-flipping is really going to be possible here. EDIT: Or to put it another way, because the video co-processor doesn't have enough memory to hold the entire image all at once time, and because the video co-processor cannot access main memory, just to hold a static photo-realistic image on the screen you're going to have to constantly copy ~300K of pixels from main memory into video memory... each and every frame. If I'm doing my math right, that'd be more than 36 million operations per second just to pump the data into the video co-processor? It reads to me like the co-processor isn't doing a great job of offloading work from the CPU here. All of these concerns might be dismissed simply by saying "the CPU is much faster than those other 8-bit platforms you're used to". Assuming that isn't the case, I'd probably like to see the video co-processor have enough memory to hold two full pages of bitmapped video. I'd also greatly appreciate it if they could arrange for direct CPU access through one of their pre-existing banked memory regions. Still, I'm eager to see how David's project progresses.

colejohnson66 7y ago
I’d assumed they’d just add more ram to the Vera chip, but I don’t know the details of if that’d be possible.
- jmccorm 7y ago
  I'd hope so. Or they could leave it in as an old-school quirk that you have to hack around in order to get the most out of a bleeding-edge vintage home computer. I'm not sure of their intent here? There's this clip https://www.youtube.com/watch?v=sg-6Cjzzg8s&t=2082 https://www.youtube.com/watch?v=sg-6Cjzzg8s&t=2082 from his "Building my Dream Computer - Part 2". I'm kind of wondering if David understands the issue, or if he just had problems communicating it to his audience, or if I'm just plain wrong and this clip is just a coincidence?