A8DS - An Atari 8-bit Emulator for the DS/DSi/XL/LL

[+llabnip]

Welcome to the newly rebranded A8DS (formally XEGS-DS).

 

https://github.com/wavemotion-dave/A8DS 

 

Given that the emulator was always a bit more than an XEGS emulator and it turned out to be a much more capable general-purpose Atari 8-bit emulator, I've decided to rebrand the XEGS-DS emulator (last version was 2.9 released in 2021) into A8DS (new version 3.0 released today):

 

 

To go with this new release is a new keyboard handler and a nice clean set of keyboard skins included:

 

 

These new keyboard skins can be picked using the GEAR icon. We have skins that cover the Atari 800 XL, XE and older Atari 400 styles so you can pick the one that best suits your tastes (the keyboards all function identically).  This is a big improvement from the aesthetically unpleasing grid-layout that was included previously.  Due to the limited screen resolution on the DS/DSi, a few keys had to be repositioned to optimize the space available. I think the placement still captures the stylings of the original machines.

 

Otherwise all the same Atari 8-bit goodness is included in the emulator. Be sure to read the updated readme.md on the main github page for how to setup and use the emulator.

 

In general this emulator supports:

 

• Memory configurations including 48K (base ATARI400/800), 64K XL/XE, 128K XE, 320K RAMBO, 576K COMPY and 1088K RAMBO
• Cart based games up to 1MB in size (.CAR and .ROM)
• XEX Atari 8-bit Executable images of any size provided they fit into the Memory Configuration configured
• ATR and ATX disk-based games (two emulated drives supported as D1 and D2)
• NTSC and PAL support
• Virtual keyboard in various Atari 800/XL/XE stylings
• R-Time8 Real-Time Clock support (mostly for SpartaDOS X)
• Built in Altirra OS (3.33) and BASIC (1.58) but optional external BIOS/BASIC support to use the real Atari firmware
• High Score support for 10 scores per game
• Full configuration of DS keys to any Atari 8-bit joystick/key/button
• Save and Restore state so you can snap out the memory/CPU and restore it to pick back up exactly where you left off

 

The use of this emulator requires that your DS/DSi/XL/LL unit has the ability to play homebrew games. For older units, this is often accomplished with a flash cart such as the R4 or one of the generic clone cards. For the DSi and above, the SD card slot on the side can be loaded up to boot the handheld directly into a homebrew launcher such as Unlaunch or Twilight Menu++.  The DSi via Unlaunch/TWL++ also will unlock the 2x CPU and 4X Memory of the DSi or above and is a better overall experience for the emulator as I don't have to resort to frame-skip to get the performance needed.

 

 

 

[TGB1718]

Looks very nice, but how do you use this i.e. install, is this on a cartridge etc. I can't seem to find anything

that says how to install it.

[+llabnip]

In the readme there is a short section near the bottom: 

Installation :

• To run this on your DS or DSi (or 2DS/3DS) requires that you have the ability to launch homebrews. For the older DS units, this is usually accomplished via a FlashCart such as the R4 or one of the many clones. These tend to run about US$25. If you have a DSi or above, you can skip the R4 and instead soft-mod your unit and run something like Twilight Menu++ or Unlaunch which will run homebrew software on the DS. The DSi has a convenient SD card slot on the side that saw very little use back in the day but is a great way to enjoy homebrews. See https://dsi.cfw.guide/ to get started on how to soft-mod your unit.
• You will the optional BIOS Files. See BIOS section above.
• You will also need the emulator itself. You can get this from the GitHub page - the only file you need here is A8DS.nds (the .nds is a Nintendo executable file). You can put this anywhere - most people put the .nds file into the root of the SD card.
• You will need games or applications in .XEX or .ATR format. Don't ask me for such files - you will be ignored.

 

I always recommend the DSi XL/LL (the LL is just the Japanese model of the USA's LL). It's bigger, bolder and generally the LCD refresh is a little slower so it more closely mimics the real phosphor fade of an old TV screen.  Such a unit will run all 7 of the emulators under my current care (ColecoDS, StellaDS, A5200DS, A7800DS, Nintellivision, DS994a and now A8DS).

[Rybags]

Looks good.  I used to have a DS Lite and Acecard 2 (I think that's what it was called) - didn't really do much emulation with it, for the most part I played Tiger Woods Golf and Metroid Prime Pinball.

 

Is it incomplete as in lacking total cart support?  That shouldn't really be a barrier, practically all types should be well documented and the various banking schemes should be reasonably easy to incorporate.

[+llabnip]

4 minutes ago, Rybags said:

Is it incomplete as in lacking total cart support?  That shouldn't really be a barrier, practically all types should be well documented and the various banking schemes should be reasonably easy to incorporate.

Correct - right now it's just .XEX and .ATR (and partially working .ATX support).  As with any emulator on a limited resource system and with limited developer time, it falls short of prefect emulation (though I'd put it in the 90% or better category). 

 

The only "cart" supported is the built-in BASIC. I'll probably add support for some of the popular cart types - I'm especially keen on making sure SpartaDOS works. 

 

It's just a matter of time and effort - I've put more than 1000 combined hours into the emulation scene on the DS since 2020 and sometimes perfect is the enemy of good enough. Burnout on any hobby project is real so I have to prioritize and balance my efforts here. 

[TGB1718]

Just had a look and I found my GBA Player and Passkey, I think it's supposed to allow you to

run .NDS images from the GBA player, just about to try it with Super Mario Bros.

 

Fingers crossed🤞

[TGB1718]

There's a shame, doesn't work with Passkey, when I select to run A8DS, it just shuts down the DS

 

[drpeter]

I'm curious- I understand the DS/DSi to have a resolution of 256x192 pixels. How is the Atari resolution of 320x192 pixels managed?

[+llabnip]

42 minutes ago, drpeter said:

I'm curious- I understand the DS/DSi to have a resolution of 256x192 pixels. How is the Atari resolution of 320x192 pixels managed?

The DS/DSi uses hardware A-Line scaling so I map the resolution down to 256x192 but you can scale it back up - it's just that it will cut some pixels left/right or top/bottom (as many games use more than the standard NTSC 192 visible pixel rows).

 

This is usually not a problem - many games just have a bit of sky/ground or don't utilize the entire edge-to-edge graphics ... and even if they do, a small bit of scaling doesn't usually hurt. It's a little tougher for games with a lot of text.

 

So witness Zork I here - if you look closely you will see some missing pixel columns. The O in ZORK here is a little squished.  I use a trick called 'jitter' such that on alternate frames I move the entire frame a half-pixel (this is supported by the DS hardware so it takes no extra CPU time). It's not something you can visibly see but it tricks the eye into thinking you're seeing the whole image.

 

Is it perfect? No. But what in life is!

 

[Beeblebrox]

ahhhh, damn my impulsive nature. Never owned a Nintendo DS or DSi so seeing this great little project/emulator I just had to pick up a cheap secondhand DSi from Ebay just now. (£25 including 4 x games and free postage). I can always sell off the games to pay for it. The idea of running some of my A8 games off this is just too appealing.

[Rybags]

They can be emulated on a low end phone so the appeal isn't what it was.  That said, it doesn't make a lot of sense doing 2 levels of emulation where you could emulate the Atari on the phone to start with.

The intended usage case - original games - didn't do a lot for me really.  There were those few games I played mostly but the rest barely got a look-in.

 

But I'm different to plenty - the only Nintendos I really ever got into were the game/watches and by the time computers became more accessable that was it.  And I never really got much into consoles or handhelds regardless of manufacturer.

 

[+Philsan]

I have PSP and PSVita handhelds with emulators but I prefer Dave's emulators for Nintendo DSi console, especially with latest updates.

 

A8DS (I'll update name) is mentioned in Topic for newbies for years.

 

CAR emulation would be nice for two games only available in cartridge format (FloB, Space Harrier - I think both use Atarimax CAR type).

[invisible kid]

About the resolution. Would it be possible to have a virtual screen of 320x192 but have a 256x192 visible pan. 99% of the time it would just automatically center, but if you wanted to see the edges you could manually pan it. Just don't like the idea of missing pixels. But more importantly, awesome job!

[+llabnip]

33 minutes ago, invisible kid said:

About the resolution. Would it be possible to have a virtual screen of 320x192 but have a 256x192 visible pan. 99% of the time it would just automatically center, but if you wanted to see the edges you could manually pan it. Just don't like the idea of missing pixels. But more importantly, awesome job!

Yes, this is possible. In fact I do such a thing on StellaDS for the homebrew games that really stretch the vertical limit. Most of the Champ Games utilize roughly 220 scanlines to pack all the graphical stuff into the screen. But the top (and sometimes bottom) is really just score and player ships remaining, etc. So I allow a full scale and you can map any buttons to shift the screen up/down and it will smoothly scroll back into place. So you can 'glance up' from time to time to see the score which works great especially for games that have a little cutscene or similar between levels. 

 

The shoulder buttons would be natural candidates to shift the screen left/right. 

 

Right now you can scroll and zoom manually but it's not really designed to take place while you're running a program. It's more to 'set your default' for that game (and you can save out the settings on a given game). 

 

Here is the same Zork I on the same DS unit zoomed in to a 1:1 ratio (i.e. 320 horizontal pixels). You can see the O on ZORK is fully formed but the screen can't fit the entire image. You can scroll it left/right but it's not ideal.

 

 

It's not optimal to have to scale things and it's not optimal to have to manually scroll. I found in practice the scaling was less intrusive than the scrolling. One of the reasons ColecoDS and DS994a work so well on the DS/DSi is that their natural resolution is 256x192 and there isn't really any overriding that. So all games look 1:1 perfect for those systems (and related systems like the MSX or the Spectravideo SVI).

[invisible kid]

Thanks for the in-depth! Very cool!

[+llabnip]

3 hours ago, Beeblebrox said:

ahhhh, damn my impulsive nature. Never owned a Nintendo DS or DSi so seeing this great little project/emulator I just had to pick up a cheap secondhand DSi from Ebay just now. (£25 including 4 x games and free postage). I can always sell off the games to pay for it. The idea of running some of my A8 games off this is just too appealing.

That's a good price - you did well. Assuming it's a normal DSi (not the XL/LL), my recommendation is to bump the default (3) brightness up a notch. The brightness ranges from 1-5 and I find that the original DSi units tend to look better with my emulator on a slightly brighter setting - I tend to use a brightness of 4 (out of 5).  If you find you're having trouble picking out very small bullets or other pixel-level details, adjusting the brightness will help.

 

The XL/LL (which are more expensive) tend to have a slower LCD decay and tend to look really good even at lower levels of brightness (2 or 3 out of 5 is fine on these units).

 

In addition to my emulator, there is another A8 emulator: Atari800-nds. It's more of a direct port done some years ago and isn't under active development. 

[Beeblebrox]

Thanks. Yes I went for the Dsi because it was a 3rd cheaper on average than the XL and I am just  planning on testing it out. Aside it being very cool to be running A8 games I like the idea of the physical control pad controls on a dedicated device such as this, which you just can't get on a mobile phone based equivalent. Also the fact it can emmulate rambo and 1088 and thus run some of my favourite games of recent years, it's worth the initial outlay. I will have to softmod it as you mentioned above. 

 

Thanks for creating this. 😊

Edited May 5 by Beeblebrox

[TGB1718]

8 hours ago, llabnip said:

Welcome to the newly rebranded A8DS (formally XEGS-DS)

I assume you need something like the R4 or it's later incarnations to run this ?

[Beeblebrox]

8 minutes ago, TGB1718 said:

I assume you need something like the R4 or it's later incarnations to run this ?

Yup, installation instructions posted earlier.

 

Edit: R4 really cheap on ebay UK

 

https://www.ebay.co.uk/itm/265808285845

Edited May 5 by Beeblebrox

[+llabnip]

17 minutes ago, TGB1718 said:

I assume you need something like the R4 or it's later incarnations to run this ?

For a DS which doesn't have an SD card slot, yes.  This is, essentially, a flash cart (using a micro SD card) for the DS much like an Atarimax cart for the Atari 8-bit line.

 

For a DSi (or DSi XL/LL or 2DS/3DS) there is an SD card that can be used to run homebrew. In this case you wouldn't use an R4 card.

 

They introduced the SD card slot on the DSi but it was woefully under-utilized during the lifetime of the DSi. But thanks to modern soft-mods, it's the easiest way to allow homebrew games to play on a DSi. Even better - using the SD card to launch homebrews will allow the homebrews to take advantage of the 2x CPU mode of the DSi (134MHz vs the original 67MHz). 

 

For either, any old SD card works fine - I think my main unit has a 4GB card that holds more than 10,000 classic games across a host of 8-bit systems and it's not even half-full. 

 

 

[FifthPlayer]

Installing this right now on my DSi.  Looking at the FAQ on soft-modding the DSi, it looks like there are several options available for exploiting the machine, and some are more compatible with games/homebrew apps than others.  I have a copy of DSi Browser and Flipnote Studio installed so all options are available to me. 

 

Is there a preferred exploit for running A8DS?

 

And at the risk of going off-topic, how compatible is your Nintellivsion emulator as compared to the official Intellivision Lives! collection for the DS?  I really liked that cartridge but unfortunately some sound effects were missing in certain games, which hurt gameplay in titles like Space Spartans and AD&D Cloudy Mountain.

 

Edited May 5 by FifthPlayer

[+Philsan]

Previously I had XEGS-DS and it worked executing roms in roms/xegs folder.

With A8DS, with roms in roms/xegs or roms folder, I get "Start failed. Error 1"

[+llabnip]

39 minutes ago, Philsan said:

Previously I had XEGS-DS and it worked executing roms in roms/xegs folder.

With A8DS, with roms in roms/xegs or roms folder, I get "Start failed. Error 1"

I assume we're talking about the Atari BIOS files? 
 

Interestingly enough, my code doesn't actually put out anything called "Error 1" so I'm not sure where that's coming from. You can send me a PM with a pic that would help.

 

If this is BIOS related, there are three places you can place the BIOS files. From the readme.md file:
 

A8DS supports 3 optional Atari BIOS and BASIC files as follows:

*  atarixl.rom   - this is the 16k XL/XE version of the Atari BIOS for XL/XE Machines
*  atariosb.rom  - this is the 12k Atari 800 OS-B revision BIOS for older games
*  ataribas.rom  - this is the 8k Atari BASIC cartridge (recommend Rev C)

You can install zero, one or more of these files and if you want to use these real ROMs they must reside in the same folder as the A8DS.NDS emulator or you can place your BIOS files in /roms/bios or /data/bios) and these files must be exactly so named as shown above. These files are loaded into memory when the emulator starts and remain available for the entire emulation session.

 

Edit: if you’re using Twilight Menu to launch roms directly then you will have to rename A8DS as XEGS-DS until Rob updates TWL++ to include direct support for the rebrand. 
 

Or you can just put the new version in the root folder and launch it and load roms from within the emulator itself. 

[+llabnip]

29 minutes ago, FifthPlayer said:

Installing this right now on my DSi.  Looking at the FAQ on soft-modding the DSi, it looks like there are several options available for exploiting the machine, and some are more compatible with games/homebrew apps than others.  I have a copy of DSi Browser and Flipnote Studio installed so all options are available to me. 

My personal favorite is Unlaunch but it's a one-way ticket (in theory you can back out of the install... but it's not foolproof). This installs custom firmware to the point where you can run anything and everything... I usually have it launch Twilight Menu++ since that's a nice GUI for your DS but you can also launch directly into any emulator if you just want a fast startup/dedicated A8 emulation machine.

 

I've also used the Camera Exploit with Twilight Menu with great success. That will work just as well but requires a couple more screen presses to launch the emulator.

Quote

And at the risk of going off-topic, how compatible is your Nintellivsion emulator as compared to the official Intellivision Lives! collection for the DS?  I really liked that cartridge but unfortunately some sound effects were missing in certain games, which hurt gameplay in titles like Space Spartans and AD&D Cloudy Mountain.

I-Lives is the reason I made Nintellivision. All the missing sounds, cut-off graphics in Tarmin and a host of other things... Nintellivision will play everything (including ECS games with speech) with a really high degree of accuracy. I'd say the compatibility is close to 98% and you would be hard pressed to play a game and not have it feel 'right' other than a slight loss of the 16-position disc to 8-way dpad. It convers all the useful expansions - JLP, special memory emulation for games like Chess and Land Battle and high-score / cheat / manual support. One of my favorite systems!  If you get it running, PM me for my custom overlay pack. I don't distribute it publicly but for personal use only I'm happy to share the overlays (the generic ones built into the emulator work fine... but are very bland). I even made the run-and-shoot dual controller action for games like AD&D Cloudy Mountain so you can run and shoot at the same time - something that was a problem even on real hardware.

 

[+Philsan]

20 minutes ago, llabnip said:

I assume we're talking about the Atari BIOS files?  Interestingly enough, my code doesn't actually put out anything called "Error 1" so I'm not sure where that's coming from. You can send me a PM with a pic that would help.

I get this error after having launched a game from Homebrew launcher. I don't think it's a bios problem because emulator should run without Atari Bios (moreover they are in roms/Bios).