2600 ST Interface

[Mehridian Sanders]

So I have a 2600 that is busted up but the three main chips are still intact and working. (Tested on a second system I retrofitted to allow Chip swapping). Emulation is one thing, however integration is another. I am looking to make or find an interface to play 2600 games through the ST. So it would send video/audio to the ST and allow control from the ST. Tricky to do but, any suggestions? not even sure this will work.

[Zogging Hell]

Think you're out of luck there, although I'm not quite sure what you want to do? Do you mean use the ST like a joystick controller?

 

The ST would struggle with live video - colour RF capture cards for the ST did exist but they struggled with a single paused screen of capture, and could only reliably grab black and white in 'real time' albeit at low frame rates and often at a quarter/ half of the resolution. If the video out isn't working on the 2600 this wouldn't help anyway.  I suppose you could capture video from lines on the motherboard itself, but then why not just use those to connect to a TV anyway?

 

The 2600 chips are actually quite difficult to software emulate for the ST, I don't think there was an ST emulator for the machine during its lifetime although I think something like the Falcon could probably manage. I think the only machines the Atari ST could emulate well were the ZX81 and the Spectrum which had really simple graphics chips (and even the Spectrum one ran slower than the real thing).

 

I suppose in theory you could develop some complex cartridge port cartridge with some sort of FPGA in it that could do the things I think your wanting, but I think you would probably have to do that yourself

 

I'm probably getting the wrong end of the stick (perhaps you mean insert the working chips in some sort of hardware interface? - but see the last point - and you probably find it easier to get a new PCB based on the old motherboard printed) but think you are going to be disappointed...

 

 

[tjlazer]

The only option would be an Emulator.  But you would need a 68030 to be able to play them at full speed.  the 8Mhz would not be fast enough.

[Mehridian Sanders]

On 6/1/2020 at 10:36 AM, Zogging Hell said:

Think you're out of luck there, although I'm not quite sure what you want to do? Do you mean use the ST like a joystick controller?

 

The ST would struggle with live video - colour RF capture cards for the ST did exist but they struggled with a single paused screen of capture, and could only reliably grab black and white in 'real time' albeit at low frame rates and often at a quarter/ half of the resolution. If the video out isn't working on the 2600 this wouldn't help anyway.  I suppose you could capture video from lines on the motherboard itself, but then why not just use those to connect to a TV anyway?

 

The 2600 chips are actually quite difficult to software emulate for the ST, I don't think there was an ST emulator for the machine during its lifetime although I think something like the Falcon could probably manage. I think the only machines the Atari ST could emulate well were the ZX81 and the Spectrum which had really simple graphics chips (and even the Spectrum one ran slower than the real thing).

 

I suppose in theory you could develop some complex cartridge port cartridge with some sort of FPGA in it that could do the things I think your wanting, but I think you would probably have to do that yourself

 

I'm probably getting the wrong end of the stick (perhaps you mean insert the working chips in some sort of hardware interface? - but see the last point - and you probably find it easier to get a new PCB based on the old motherboard printed) but think you are going to be disappointed...

 

 

Well, I have worked with the TI-99/4a and created some of the newer items for it. FinalGROM99, Sidecar 32k RAM, etc. I do love making new things for older systems that improve their use. I am thinking about a Cartridge port connection that would be able to translate Atari 2600 cartridges to the ST. For Instance, in a very basic representation. 

 

2600 Cartridge  -> Connection to (Some micro-controller to translate signals) -> Atari ST cartridge port - Able to be played on 1040 / 540 with joystick from ST. 

 

I have been trying to find a listing o cartridges for the ST but I am not having much luck with my Google. This has been a semi-search, as I only have so many hours with 3 sons and other projects. Even a Multicart for the ST would work. Will look for those as well. 

 

is there a good list of DIY home projects for the ST? or rather one you would recommend?

 

Thank you all for your patience and info.

[Mehridian Sanders]

There are a lot of ports which will go unused. Hard Drive.. Modem.. Seems like a RPI Zero W could emulate some of these functions. Put an IDE / SCSI controller addon into it.

 

I have seen peripherals like UltraSatan Drive, which I am looking forward to building. 

[Zogging Hell]

Ah ok I see what you are aiming at. I can imagine that a cartridge port connector could in theory be built (there aren't many cartridges for the ST, only a programming language Fast Basic and a few utilities for software, on the hardware side it got used more diversely for scanners and lego robotic interfaces for example). I suspect if you track down the developer docs and check out the schematics that would be the place to start. I imagine some of the more technical ST magazines from back in the day had some projects for the cartridge port, so some of the German magazines might have something (ST Computer). The only really 'high tech' cartridge (that isn't more than an interface) I can think of that even did anything vaguely like you mention would be that 3D add-on cartridge (the video is on Youtube).

 

I think the main problem will be the ST running the game itself, I'm not exactly a technology knowledge titan (or at all even), but I imagine the custom chips in the 2600 will be a bit tricky for the ST to handle in software, the architecture is pretty different to the ST (even if, or perhaps because, it is quite primitive), but I guess you are thinking of using your spare chips in this interface? I would imagine the cartridge would have to do all the heavy lifting and then translate the output into a format the ST can put on screen, but this seems like quite a heavy duty project.

[ParanoidLittleMan]

" ... 2600 games through the ST. So it would send video/audio to the ST and allow control from the ST. "

Well, I don't see the point in this. Why not sending video and audio to monitor (TV) directly ?  Control from the ST instead using joystick and couple switches of 2600 ?

 

"2600 Cartridge  -> Connection to (Some micro-controller to translate signals) -> Atari ST cartridge port - Able to be played on 1040 / 540 with joystick from ST.  "  Hmmm ...  Cartridge is just a ROM with connector. There are no video and audio signals.  As others said, you need emulator of 2600 CPU, video, audio, etc. circuits to make game on cartridge work with ST. And it's just slow for that.

 

Considering ST cartridge port: it's purpose is mostly diagnostic - for repair, troubleshooting. Not used for games - and reason would be higher price that floppy, limited capacity, read only. Although with special tricks all it can be overridden. And there were made some really complex cartridge port interfaces/adapters for ST.

I think that most complex is NetUsBee - LAN, USB port, even hard disk mode (little slow though) . Myself have experience with it. Made EPROM programmer for it back in 1987. And some 10 years ago very fast IDE/CF card adapter as hard disk:  http://atari.8bitchip.info/astide.php

 

I don't think that there is lot of ports unused on Atari ST. Everything can be used, even today. Serial, parallel for instance for communication with PC, even if it has only USB. ACSI (hard disk) port is probably most used, even now because of SD card adapters made for it (UltraSatan, Gigafile ...) . Cartridge port as mentioned ...

 

But using some console game cartridge (or some C64, TI-99 game cartridge) is different story. It needs emulation of particular machine. And that is most likely already done - not for ST . So, maybe using some Raspberry for that ? Then you just don't need ST - with it's analog video output.

 

Btw.  I converted some ST games for using with it's cartridge port. But it runs from RAM, as original game. Cartridge is just for storage - some people wanted it so.

Even if could solve that some Raspberry or whatever serves ST with video and audio (so emulating 2600) that should go in digital form. And ST could read video enough fast. Audio would be bigger problem - ST has only programmable sound chip. So rather some STE with it's DMA audio. And controls would need trick to solve write to cartridge port. 

Well, I recommend some other project, and that should be something simple, for start ?

 

[Mehridian Sanders]

On 6/3/2020 at 4:39 AM, ParanoidLittleMan said:

" ... 2600 games through the ST. So it would send video/audio to the ST and allow control from the ST. "

Well, I don't see the point in this. Why not sending video and audio to monitor (TV) directly ?  Control from the ST instead using joystick and couple switches of 2600 ?

This should be easy to accomplish with a toggle switch some DB9's (male and female) and some through-hole soldering skills .... 3d Printer if you want it pretty. 

On 6/3/2020 at 4:39 AM, ParanoidLittleMan said:

Considering ST cartridge port: it's purpose is mostly diagnostic - for repair, troubleshooting. Not used for games - and reason would be higher price that floppy, limited capacity, read only. Although with special tricks all it can be overridden. And there were made some really complex cartridge port interfaces/adapters for ST.

I will do some research and see what I can find. This is excellent information.

On 6/3/2020 at 4:39 AM, ParanoidLittleMan said:

I think that most complex is NetUsBee - LAN, USB port, even hard disk mode (little slow though) . Myself have experience with it. Made EPROM programmer for it back in 1987. And some 10 years ago very fast IDE/CF card adapter as hard disk:  http://atari.8bitchip.info/astide.php

Now we're talking... I see that people were having problems creating the PCB, on last update. I will read this page thoroughly. 

On 6/3/2020 at 4:39 AM, ParanoidLittleMan said:

Well, I recommend some other project, and that should be something simple, for start ?

This is the most sensible. I tend to jump into a hard project first, and work until it is accomplished. There is still much I do not know about the Atari ST. When I got into my TI-99/4a, I built my own FinalGROM99. I ended up making

my own AVR Programmer, along with my FG99. I also learned how to use the AVR programmer. The MIDI ports interest me. I must learn more about the interfaces. I have some DB breakout connectors coming soon. With any luck something will shake loose from my brain. Too many marbles missing already ?

 

DB25 Breakout Board Solder-Free Male Adapter

D-SUB DB15 Male 15Pin

[Mehridian Sanders]

I detest waste. I would like to see the cartridge port put to some use. hmm... 

 

ah HA something a bit easier.

 

https://www.atarimagazines.com/v4n12/STCartridges.html

 

and one for you @ParanoidLittleMan

 

http://atari.8bitchip.info/cartST.html

Edited June 5, 2020 by Mehridian Sanders

[Mehridian Sanders]

so the cartridge port is pinned as such 

and the RPI zero Pinouts. 

I shall work on it.