[HN Gopher] Micro Beast: Self contained 8-bit computer kit in a box
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Micro Beast: Self contained 8-bit computer kit in a box
Author : throwaway71271
Score : 74 points
Date : 2024-01-05 11:12 UTC (11 hours ago)
(HTM) web link (feertech.com)
(TXT) w3m dump (feertech.com)
| uticus wrote:
| > Goals > "These are my principles, and if you don't like them I
| have others." - Groucho Marx
|
| Love it. Great combination of hard work (emulator available!) and
| lightheartedness.
| ithkuil wrote:
| Perfect for 1-D pacman!
| Koshkin wrote:
| ... or Tetris
| Duanemclemore wrote:
| And DOOM of course.
| avhon1 wrote:
| I don't think a 10 MHz Z80 and 512 KB of RAM is enough for
| DOOM as we know it. There are some games called "doom" for
| the similar Ti 83/84 calculators, but they're more similar to
| Wolfenstein 3D: very cut-down from what DOOM is actually
| like.
|
| https://www.ticalc.org/archives/files/fileinfo/238/23843.htm.
| ..
|
| https://www.ticalc.org/archives/files/fileinfo/419/41975.htm.
| ..
| fwsgonzo wrote:
| Yes, you're right. I don't know if you can see this:
| https://i.redd.it/vtswj6s8wh321.jpg
|
| But what it says is that it required 24MB of HDD (12MB
| after installation), and a 386 or equivalent computer. An
| i386 is quite powerful, to be honest. It even has protected
| mode!
|
| And, 4MB RAM, which is more than what I had on my 286
| laptop back in the day.
| throwaway71271 wrote:
| I feel like there is a computing renaissance, so many new and
| creative projects, I am not sure if its because of pcbway or
| because of riscv, cheap parts, accessible knowledge, kicad and
| opensource tooling, but it makes me super excited.
|
| People are having fun with computers.
| Duanemclemore wrote:
| Yeah, it really feels like people are going back to the
| pre-5150 personal computer era and looking at things from the
| ground up again.
|
| This is especially exciting to me as someone juuuuuust old
| enough to have extensively used those machines (C64, //e, Atari
| 800, etc) when they were contemporary but now diving deep into
| an interest in the fundamentals of computing while in the
| middle of a completely different career. A project like this is
| specifically exciting because I could look at 8 bit computing
| from the ground up without having to worry about buying a
| vintage machine and a whole host of gremlins it might have
| built up over the years.
| mechagodzilla wrote:
| I'm too young to have participated much with 8-bit machines
| the first time around, but I've played around with Z80 + CP/M
| machines (both vintage and new/custom) a lot in recent years.
|
| To me it is an extremely fun, human-scale design space.
| Machines of lower capability are mostly toys or needlessly
| painful, but an 8-bit CPU running at a few MHz with 64KB of
| RAM is enough to provided a very nice text-only computing
| experience. You can run self-hosting development tools (Turbo
| Pascal!), get access to all kinds of CLI tools, real file
| systems, etc, while still keeping the entire memory map in
| your head.
|
| I love the idea of a computing environment that just provides
| you with a thousand fully-independent, 64KB 8-bit machines
| and just drops time-slicing and task switching completely.
| bluescrn wrote:
| A lot of things came together over the last decade or two to
| enable ever-more-impressive 'maker'/hobbyist projects.
| Ubiquitous 3D printing, cheap PCBs, powerful CAD software
| available to hobbyists, YouTube's growth as an educational
| resource, excitement over FPGAs, super-affordable
| microcontrollers and single-board computers, and a big wave of
| 80s/90s nostalgia often giving it direction.
|
| At the same time, modern 'mainstream' computing has become
| increasingly user-hostile, built to encourage spending, ad-
| views, and content consumption rather than experimenting and
| creating.
| phkahler wrote:
| That's a LOT of RAM for an 8bit, and to think it has no video
| display.
|
| This is not the 8bit world so many cut their teeth on, it's Kim-1
| or Altair era but with more memory than anyone knew what to do
| with.
| mkesper wrote:
| This is a CP/M 2.2 installation, with the CCP loading from
| address D800h giving approximately 54Kb free for user programs.
| The system supports two 248K drives - Drive A is in ROM (and
| therefore readonly at present) and Drive B is in RAM.
|
| Seen like that, you could have something like that on a C128, I
| guess.
| whartung wrote:
| Adding video is apparently quite difficult.
|
| Apparently it's straight forward to breadboard a legacy CPU
| today and get serial I/O, which solves many ills. But getting
| video is a large wall to scale.
|
| There have been several video solutions out there that folks
| have made. I think Ben Eater has a video of banging together
| something that can drive VGA (but not, necessarily, what one
| would consider "video" for a computer).
|
| The original home 8-Bit computers were essentially video
| display systems that had some spare cycles to actually run some
| software. The fundamentals of the system design revolved around
| the video. Everything was a slave to the video clock cycle.
|
| There is no real one chip device folks can drop on to a CPU bus
| and "get video", not that I've seen yet, especially not the way
| folk remember the 8-bit experience with memory mapped video.
| Even integrating something like the ubiquitous 6845 (which was
| used everywhere back in the day) is challenging, as it's not a
| one chip solution, plus, today, interfacing it to a generic
| HDMI monitor is a trick. (Also, I'm not sure today how
| availability of the 6845 is today.)
|
| Even the Commander X16, which went through great lengths to
| reinvent the 8-bit experience, created their own video chip
| (FPGA I think), and it does not share video memory with the
| host 6502, it use a memory mapped I/O interface.
|
| Then, of course, there's things like a Raspberry Pi 0, that (in
| theory) can be bought for $10. Tie that to the serial port, and
| host some software on it, and it can do all sorts of amazing
| things far faster than a 10MHz Z80.
|
| The original creator of this kit (which by the way, looks like
| a really nice, well packaged kit) had this as an original goal:
| * Genuine 8-bit design, don't cheat with "support" processors
| that are more powerful than the main CPU.
|
| Obviously, a Rasp Pi is quite disqualified from that. And, to
| be fair, I'm going to quibble, because the CP2102N chip they
| use for USB connectivity is likely a powerful CPU, more
| powerful than the Z80. You have to be to be able to drive USB
| 2.0.
|
| But I can't condemn them for that, the addition of the UART
| talking to the CP2102N is a very good design. And adding USB to
| the system opens it to a huge variety of peripherals. With that
| clock chip, they can go to 56K baud, that's 5K Bps. That's fast
| for a floppy at the time. Slow for a hard drive, but overall
| not too bad.
|
| At 10MHz, they might have got better transfer rates with a bit
| banged SPI USB driver.
| crq-yml wrote:
| I think the phenomenon of "underpowered host commands OP
| support" is somewhat inevitable in this "retro remake" space.
|
| Uzebox, one of the first projects of this type, found a path
| with the ATMega that really does it all-in-one, but the
| compromise is great - NTSC video, the available space is tiny
| and shared with the software kernel, and you have to program
| it externally. It's not a complete computer.
|
| The Agon Light goes in the direction of completely embracing
| a serial "eZ80 talks to ESP32" architecture, thus achieving
| its boast of being the "fastest 8-bit" by not really
| constraining itself. It's elegant for what it is; video games
| really DO benefit from that kind of setup since they
| typically operate with relatively light gameplay logic
| driving a massive amount of graphics.
| xcv123 wrote:
| > And, to be fair, I'm going to quibble, because the CP2102N
| chip they use for USB connectivity is likely a powerful CPU,
| more powerful than the Z80
|
| It's a black box transceiver with no CPU functionality
| exposed.
|
| https://www.silabs.com/documents/public/data-
| sheets/cp2102n-...
| Duanemclemore wrote:
| It's perfect for CollapseOS http://collapseos.org/
|
| I know the point of it isn't to run on new hardware, but this
| would be a way to learn it on a stable platform without having to
| worry about dealing with constant problems from old hardware
| before trying to implement it on said.
| 01100011 wrote:
| I'm not sure why there is an obsession with 8-bit architectures
| for these sorts of projects. Are there no 32-bit CPUs with a
| simple architecture and easy programming model? I say this as an
| old fart who has a great deal of nostalgia for the 8 and 16 bit
| days. If I were teaching my kids computer architecture these
| days, I don't think I'd start with an underpowered, out dated
| arch.
| avhon1 wrote:
| > Are there no 32-bit CPUs with a simple architecture and easy
| programming model?
|
| There really aren't. You could consider Arm (maybe with the
| simplified but 16-bit "thumb" instruction set), or MIPS, or
| RISC-V. Between all of those, it's rare to find bare CPUs;
| usually you get them in a system-on-a-chip, with things like
| DDR memory and other sophisticated peripherals built-in. You
| need complicated drivers and a bootloader, maybe even with
| signed payloads. Nothing as architecturally simple as wiring
| the address and data lines of a CPU into the address and data
| lines of some RAM or 7800 logic directly wired into a keyboard.
|
| In principle those devices could exist, but as a hobbyist you
| can only really get your hands on hardware with that kind of
| conceptual simplicity by either programming it into an FPGA, or
| by using hardware that dates back to when that approach to
| computer design was cutting-edge.
|
| edit: you could maybe consider some kinds of microcontrollers?
| The Parallax Propeller comes to mind.
| spc476 wrote:
| The Motorola 68k series. A very nice 32-bit architecture that
| was fun to program. The downside, Motorola isn't making new
| ones, and I'm not sure who owns the property. Another nice
| 32-bit architecture was the VAX. It had the most regular
| assembly language I've ever seen, despite being a CISC
| architecture. But sadly, both are obsolete these days.
| avhon1 wrote:
| Freescale owned the IP after Motorola, and they've since been
| acquired by NXP. For now, they are still available in the
| form of the derivative (simplified) ColdFire processors.
|
| Available ColdFire ICs:
|
| https://www.nxp.com/products/product-selector:PRODUCT-
| SELECT...
|
| Differences between ColdFire and 68k:
|
| https://microapl.com/Porting/ColdFire/cf_68k_diffs.html
| noone_youknow wrote:
| Probably not exactly what you're looking for (since you mention
| "outdated") but there are similar projects with 16 and 32 bit
| architectures, e.g. https://github.com/rosco-m68k/rosco_m68k
|
| (Disclosure: I'm the designer and lead developer on that
| project).
| 01100011 wrote:
| Cool. It's more or less what I did for my senior project back
| in the late 90s. I think the 68k is the perfect choice for
| something like this due to the simplicity and much more
| reasonable performance compared to, say, a 6502 based design.
| noone_youknow wrote:
| Thanks I couldn't agree more, the m68k is a great
| architecture, powerful enough yet simple enough that a
| person can keep the whole thing in their head.
|
| That said, we _do_ have a slightly-related 6502 too
| https://github.com/rosco-6502/rosco_6502
| fiscalnonsense wrote:
| The arrow keys seem to be placed for maximum torture, which was
| pretty typical in the 8bit era.
|
| Inverted T forever.
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