Project APS: a new Z80-based retro computer for 2024
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- čas přidán 3. 06. 2024
- The APS is one of many computers I come up with while designing the HEC. It's my response to the 'modern retro computer' trend of adding a bunch of graphics modes and overpowered sound to an 8-bit CPU to create a 'super 8-bit retro computer'. In my opinion, those computers are only 8-bit in name (and CPU) but doesn't catch the spirit. The specs of the APS is designed so that it can be released in 1986. However, this approach is also the reason why I predict the demise of this project. People love to see supercharged version of their childhood favorite which had all the features they saw in arcade machines, not 'yet another 80s home computer/console that no one has played before'. But I'm putting it out here so if you like it, please leave a comment in the comment section!
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chapters:
00:00 What is the APS?
02:30 The specs
04:10 Graphics system
11:54 Memory map
12:45 IO map
13:39 Why is it pointless? - Věda a technologie
![A new OS for the Z80! [Open Source][Zeal 8-bit OS]](http://i.ytimg.com/vi/5jTcWRN8IbA/mqdefault.jpg)
It's never pointless if you have fun doing something. Even better when you share that fun.
I think FPGAs in retro computing is extremely cool. It's kind of like taking it to the next level by designing hardware that could exist in that era.
Z804LIFE ! Make the T-Shirt Designs of your Heart;'s Desires...
"don't click away!" 🤣
Andy, the Windows Pocket PC 2000? had excellent looking colour ramping and shading. The 1980's Amiga and Acorn Arm Risc computers tried this. But, it means smooth ramping and shading, requiring many colours, but looks beautiful retro. One new Atari 7800 game tries it, but it fails, due to 4 colour objects. While you can ramp the background from colour to colour using interrupt, it's messy, and doesn't ramp horizontally. So, a large number of these fill colours are needed for those ultra retro games (the best retro games, but still simple graphics, just lots of shades and lots of colour. Venus the fly trap on Amiga, I think, tried to be like that).
The Mattel Aquarius presentation on the graphics, sounds a lot better and well featured than the X16/Next, at the time (without upgrades).
320*240 is blocky on big TV's we have today, and my favourite, Atari Lynx, far behind at 160*100. 640*480 looks more like the old 320*240, but not widescreen (854) which is excellent for gui productivity, and your wide screen gaming. 1280*720p is not pixel compatible and you start to loose the retro pixel coarseness. Now, 640*360, is widescreen, also fits in 1080. 960*540 also fits in. It's preferable.
The number of typos in your comment makes it a bit hard to read... Also, how is the Aquarius graphics better than the X16?
@@andyhu9542 Thanks. Sorry. Have dysgraphia medical condition but trivial (and google auto spell corrector has moronia).
Sprites, tiles, planes. I forget the colour and resolution. But was impressed at how much more it was. You get different groups of object graphics types, so planes makes it simpler to program, with less mixing and unmixing bit graphic bit maps. Sprites help, but anything bigger than a sprite as an animated special land scape feature is going to have to consume more sprites, or be cpu drawn into the background. The cpu/memory constraints takes away cycles. Any big sized sprite, then that is like a plane, and it doesn't matter. You should look at the Atari 7800 scheme. It was good for the time, but needed to do it with more sprite like objects. It was close. I think Atari has a proposal before the Flare team came, for a graphics system like my proposal for the 2600, where you don't move, or blitter, graphics memory, everything is sprite like objects. The CPU then does little with graphics but change position and attributes pointers. Leaving a lot more for game logic. The 1 mhz 6502 with 32MB memory, could play sophisticated 2D games.
4:49 16/32 bit z80 as fast as possible.
854*480 256 colour per plane, per sprite group. 16, 4 and 2 colour modes.
Basically an Amiga or Acorn ARM machine alternative, upgraded to what we wish they could do. Will give a similar course pixel feel on big widescreen TV, as 320x240 on an old 8 bit computer.
PS2 is now rectro.
The issue is, 16/32-bit Z80 is not produced anymore, and they are almost impossible to find. The closest thing you can get is an eZ80. In which case, the Agon Light is probably for you.
@@andyhu9542 Argon is a PICO with a z80. :)
Shame there is no 16 bit version now.
Thanks Andy.
i am instantly onboard with anything that uses my beloved yamaha fm chips lol
Andy: 64 KiB of RAM!
Me: 🤯*imagining implementing higher order data structures for my retro game logic*
Haha. Most people simply don't have the appreciation of how big 64KiB is. But NES programmers are the real hardcore programmers!
Add some quirky options to your gfx and sound that are hidden away as register flags. That offer something like a burst data mode or blit option or some sort of palette flipping effects - something unique
Interesting. Why do you suggest that? Do you think the current design is too 'vanilla' retro graphics?
@@andyhu9542yes I do believe you have the vanilla part - many of the great 8 bit computers/consoles had points of difference that developers would take advantage of to create games that were a unique experience on a particular console. Example. Commodore 64 had a fantastic sound chip and hardware scrolling, max 2 had great colour modes, nes allowed additional chips in cartridges
@@sergeinester6261 haha you got it right! Being vanilla is the point of THIS design. However, you may notice that in the video I say I have designed many computers. A lot of them do have their own quirks. Therefore, I suggest you subscribe to the channel for future videos on those machines!
@@sergeinester6261 by the way, what is a max 2? Do you mean MSX2? If you are thinking about the 19268-color modes, they came out on the MSX2+, not MSX2. (However, 256x192 at 256 colors on the MSX2 is also impressive)
@@andyhu9542 Thanks for the heads up -I will do it love these fantasy systems. Something novel would be to have a basic polygon layer you like 1 textured polygons per 8 scan lines (or similar) mixed with a blit option to pick a piece of screen and deform and warp. This would allow many effects Very much what I’d call “in between “ generation tech that something like the Konix system was proposing.
I've been fiddling with a deliberately retro original design for a 16-bit-era console (inspired variously by the SNES, Neo Geo, and Amiga, to a lesser extent by the Mega Drive/Genesis), and my reasoning for why it'll never happen is similar: it won't be compatible with any existing games, so it wouldn't hit the actual nostalgia market, and anybody who wants to make a retro-/styled/ game can do so on more advanced modern hardware with all the conveniences those offer (high-level programming languages, not being locked to a particular color gamut, Steam downloads, etc.). There's really no point to the thought experiment beyond an excuse to teach myself about how these systems work, and to see what I can come up with. And that's fun!
You know what? I have a project leopard that does the same (16-bit-era design).
Zilog's Z84C series are going end of life! They will no longer be manufactured after June 2024 :/
I'm currently making a gameboy color game and man, these specs would be _so_ freeing compared to what I've been working with.
And yet there are still people wanting me to add more features... (for example, a 50MHz eZ80)
Would be interested in your thoughts about a 6809/6309 system. Are there any of these cpus that are 10mhz or faster?
The biggest issue with the 6809 and 6309 is clock speed. The 6809 never went pass 2MHz (probably because anyone who needs more performance went for the 68k), and the 63C09 allegedly run at 3.58MHz. Wikipedia says someone has overclocked it to 5MHz but that's the end of the road for the most advanced 8-bit CPU. (Honestly, with its 16-bit accumulator the 6809 can be classified as the weakest 16-bit CPU with a bit of a stretch. No one calls the 8088 an 8-bit CPU despite it having an 8-bit data bus and using a similar approach to 6809, 16-bit registers, mostly 16-bit instructions, using the second byte of the instruction to indicate addressing modes, etc.)
@@andyhu9542I was thinking maybe a 6502 from WDC might be an acceptable alternative. It is true 8 bit, is available today, and goes up to 17mhz (20 unofficially) which gives you a dream machine for 1980, but is still limited enough to probably give that limitation that some programmers crave.
You ought to consider the 65c816
- it clocks fast and allows good access to 24-bit addressing...
- a bit more interesting than sticking with the Z80 or 6502 (IMO)
I don't know whether you have seen the instruction set of the 65C816: it's less '24-bit addressing' and more '256 16-bit address spaces glued together'. This makes the extended memory very clumsy to use and is the reason why I'm not using the 65C816.
@@andyhu9542 Yes, I do know the instruction set - and it looks interesting to me. I did a lot of 6502 programming back in the day, and going back to that doesn't really appeal .. lot and lots of instructions to do anything. The 65C816 would be interesting as it's 6502-like, but with many more instructions and addressing modes. I've done some Z80 coding, but not a huge amount... anyway, it's just my personal opinion... 65c816 is 8-bit, but with some new things to learn...
@@FlyingPhilUK Then I would suggest looking at the SNES or Apple IIGS. Both systems are superior to the one mentioned in this video in terms of sound and graphics. I like to 'pair' or 'balance' my systems, and those two systems are (in my opinion) suitable pairing for the 65C816. Putting a 65C816 in this system is like putting a V12 in a civic.
@@andyhu9542 Yes, those were the two successful products that used the 'c816...
- I'll probably have a go at a '816 project based on something from the Mister Project...
The c816 is just an enhanced 6502.. and your VDP is quite fancy.. better than Apple II GS and probably better than SNES...
quick question: have you written or tested the HDL for the fpga? (for the APS or the new computer you are designing) I'm asking because I've made an fpga graphics chip, and it was not easy. Admittedly, I had the constraint it had to fit into 32kib of ram, use only block memory, and run at 81mhz, but I just could not meet the requirements if I tried to squeeze in sprites. I'm just curious how you implemented sprites (if you have, that is.)
I have written some HDL code for this as a learning experience. But I haven't started synthesizing the code for a particular FPGA. I wonder which FPGA do you use? How many LEs does it have? Also, I think the 81MHz clock is WAY too high, even for VGA output.
@@andyhu9542I was using a basys3 dev board, which has an artix-7 with 35k logic cells which is aproximately equivalent to 52k LEs. The 81mhz restriction was actually because my only VGA monitor will only accept a 1368x768 resolution signal, which requires that 81mhz pixel clock. I could have halved the pixel clock down to 40mhz, but I was using the graphics as a way to test a CPU I was designing, which is just about capable of running at 81mhz, and using multiple clocks is a huge hassle. I was able to squeeze in a good amount of features into the VDP, though. You could section off the screen into separate windows, each with a different graphics mode, and it had a 2-color 640x384 bitmap mode, which was also an 80-column text mode.
👍 Better 🙂
I don't understand have you heard of the ez80190 at 50 mhz no?
Yes I have, how about that?
Post new video! 😉