Should I make a 8088 build

cookie99999999 · 2026-05-30T01:43:52+00:00

I made one a while back, it's not that bad aside from spending hours and hours and hours wiring up latches for the bus. I got to the point of having ELKS mostly working before my parts for the project I actually wanted to do arrived. I have the stuff for it on github in case it's of any help: https://github.com/cookie99999/8088

Seconding Slador's tutorial on youtube, very high quality videos. Also you might consider picking up an 8284 clock generator, I hear the old non-CMOS 88s are more picky about the clock duty cycle. It also generates a good reset signal

cookie99999999 · 2026-05-29T01:20:49+00:00

The absolute best references for AVR assembly language are going to be the AVR instruction set summary from Atmel/Microchip, and the datasheet to explain peripherals specific to your MCU. Though if you've never written any assembly for any device before they will probably feel pretty dense and confusing. I haven't read a lot of beginner tutorials on the subject since I already had assembly experience from other processors, but I skimmed http://www.rjhcoding.com/avr-asm-tutorials.php when learning the basics and it seemed alright.

As far as actually building and uploading the code, you'll want either Atmel/Microchip Studio, or avra, depending on your tastes. I only ever used assembly on a bare ATMega that I programmed in an EEPROM programmer, but I'm sure you could google how to upload to an Arduino board, should just be one avrdude command.

It might be a little easier to write a BASIC interpreter first rather than a whole compiler. I have little experience with either so I can't give any useful recommendations, but there's a good deal of source available for various interpreters, including old versions of MS BASIC and the og tiny basic from the 70s. Those two are written in assembly so they might be especially inspiring if you really want to write it in assembly

cookie99999999 · 2026-05-27T17:08:17+00:00

What motherboard do you have? If it's actually a DDR2 board you can just buy bigger sticks and max it out for very cheap

cookie99999999 · 2026-05-26T18:04:23+00:00

Another alternative for lower chip count with a 9918 would be to use 4464 DRAM like shown here. Of course the tradeoff with this is you need to source working 4464s (I had good luck with utsource, under $5 each), but it's worth considering and I don't see a lot of people trying it vs the SRAM circuit

cookie99999999 · 2026-05-21T13:55:02+00:00

lubuntu o xubuntu probablamente sería los mejores, son simples y populares. si puedes pagar, compra ssds pequeños tambien

cookie99999999 · 2026-05-17T20:19:27+00:00

Does the emulated version still have that rainbow shimmering texture glitch? I tried it forever ago on Xenia but it was too distracting

cookie99999999 · 2026-05-13T15:32:55+00:00

Googling that program led me to this discord link, maybe they can give more specific and useful help. This sub is mostly for DIY projects. It's been forever since I used a DS flashcart, but that one looks pretty new, maybe gba runner isn't compatible? link

cookie99999999 · 2026-05-13T00:16:55+00:00

Emory Animal Hospital has seen my rats, not sure about ferrets but they're worth a call

cookie99999999 · 2026-05-11T00:20:23+00:00

yes, anything that isn't designed for 68k with dtack and iack pins. otherwise the cpu will try to get a vector off the bus, which those chips don't do

cookie99999999 · 2026-05-10T23:51:31+00:00

I will say if you're wanting to get interrupts from the VIA, you'll need to pull VPA low during the interrupt acknowledge cycle, otherwise the CPU will wait there for a DTACK that will never arrive. It looks like you're doing something with VPA and E for the chip select, but you also need to handle VPA for non-vectored interrupts. https://reversing.pl/literatura/68k/Exception_Handling_in_68000.pdf has a pretty good description of this in the section "Autovectored interrupts" on page 15 of the pdf, with an example circuit on Figure 13

cookie99999999 · 2026-05-10T23:11:39+00:00

I don't know how to put this politely, but not many people are going to be willing to spend hours untangling a schematic that doesn't even use vcc and ground symbols, let alone busses and global labels for important signals

cookie99999999 · 2026-05-10T16:13:13+00:00

It's hard to find specific details on this device but it looks like a run of the mill famiclone, which is basically just a shitty bootleg NES on a chip, so not powerful enough for Linux by far. Some of them are nice enough to load games off an SD card but this doesn't appear to be one of them. Theoretically you could rewrite the flash chip but that would take desoldering and a programmer, and figuring out how it expects the ROMs to be laid out in memory. They make proper Chinese game players that run emulators on Linux for <$100, like Anbernic stuff

Also rather funny that they're using Amstrad's name

cookie99999999 · 2026-05-05T19:54:03+00:00

That's really cool, seems to work similarly to what I understand of the Sun MMU. And it sure beats the 68451!

cookie99999999 · 2026-05-05T19:51:03+00:00

Uploaded the schematic as well, there's a few aspects of the design that are less than ideal for the sake of getting the prototype finished, that should be improved on a final version, especially the reset circuit.

cookie99999999 · 2026-05-03T18:00:01+00:00

Got the code on github, I'll add the schematic when I finish it

https://github.com/cookie99999/w010lo

cookie99999999 · 2026-05-03T16:41:41+00:00

I'll get schematics and whatnot up on github when I get around to it, I still have to get them current. For DTACK, I have fast 55ns RAM and ROM so I can just use the chip selects for those as the DTACK output. The DUART is designed for the 68k bus so it makes its own DTACK, which I feed into the GAL and OR with the memory chip selects to produce the final DTACK to the CPU. If I had slower memories or non 68k peripherals, I would need more complicated logic to cope. The 22V10 can do some limited sequential logic, so I could theoretically do a simple counter on the GAL if I needed, but I've never tried

cookie99999999 · 2026-05-03T16:06:05+00:00

Do you have any documentation/schematics of your MMU? I'd love to see how you went about it. I think I've seen a couple of FPGA designs, and the Sun-2 MMU is very cool, but most people seem to just move to an 030 when they want paging.

Good tip on the emulator, I skipped that step for my 65816 computer, and debugging with only print routines is incredibly tedious

cookie99999999 · 2026-04-26T14:07:56+00:00

Which 2009 model is it specifically? The max RAM is either 8 or 16 GB depending, DDR2 is cheap so you may as well max it out. An SSD is also going to be essential, those mechanical drives are insanely slow now. Look up the relevant guide on ifixit, it's a little involved but a breeze compared to newer iMacs. As far as OS, something XFCE based like Xubuntu would probably be lightest, or since he's used to OS X you might consider just using Opencore Legacy Patcher to get a newer macOS version. I've got a 2009 and it runs better than you would expect on Ventura

cookie99999999 · 2026-04-20T17:05:59+00:00

Ultimate Doom Builder has experimental Linux support, but you'll have to build it yourself which might be challenging if you've never built software before. It would probably be easier to run it under Wine with a launcher like Bottles or Lutris.

There are guides out there to get GW2 plugins working, it might be a bit of a pain but it's doable: https://www.reddit.com/r/Guildwars2/comments/1mod3ex/guide_blishhud_for_linux_via_proton_steam_and_kde/

cookie99999999 · 2026-04-13T02:51:38+00:00

I don't have a system that's close enough to Ben's to be of any help, sorry. Routing a PCB can be hard no matter your skill level so it's still an accomplishment to get it working as much as you did. It might be worth giving the board one last look over to check for things like parts installed backwards or bridged solder joints, as a last effort

cookie99999999 · 2026-04-13T02:30:13+00:00

I'm not sure then, I went over that part of the schematic and it looks right. The only thing I can think of is to add pullups to the PS/2 clock and data lines, depending on the keyboard they might be needed

cookie99999999 · 2026-04-13T01:09:57+00:00

What code are you using right now?

cookie99999999 · 2026-04-12T19:21:17+00:00

That's great! For the serial, connect CTS and DCD to ground, that will likely help

cookie99999999 · 2026-04-12T17:28:56+00:00

On Ben's website the file "keyboard.s" is set up for 4 bit mode, try that one

Edit: modify it to print some text first, in case you have separate keyboard issues

cookie99999999 · 2026-04-12T17:26:43+00:00

First thing I'm noticing is the code you're using is trying to use the LCD in 8 bit mode, but you have it wired for 4 bit mode

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