Raspberry Pi and an A500 expansion thought experiment

[jackflash]

Has anybody thought about using the Raspberry Pi as an Amiga 500 accelerator/expansion board?

I  think this could be used but with the board designed to plug directly  into the 68k socket and running a 68k emulator on the Pi  https://www.raspberrypi.org/products/compute-module-development-kit/

You could use the other features on the board such as Video output for RTG

I'm not an electrical engineer or programmer so it's out of my league

[whabang]

Has anybody thought about using the Raspberry Pi as an Amiga 500 accelerator/expansion board?

I  think this could be used but with the board designed to plug directly  into the 68k socket and running a 68k emulator on the Pi  https://www.raspberrypi.org/products/compute-module-development-kit/

You could use the other features on the board such as Video output for RTG

I'm not an electrical engineer or programmer so it's out of my league

The thought has struck me - the problem is that I doubt the Pi would be able to boot fast enough to actually be a usable system as a proper emulator.

The easy way would be to build an interface from the Amiga to something like a Zero, and then write an API on the Pi for running computing tasks for the Amiga.

That way, you could write datatypes, libraries and such, which would then connect to the Pi, run the code and return the result.

On the other hand, I doubt that it would be worth the effort - there is only so much to gain from such a setup.

[Acill]

Or you can use it with UAE on it and hide it in an A500 getting better results?

[johnklos]

The Raspberry Pi doesn't have enough pins, nor the speed to react to those pins, to replace an m68000 processor. You'll just have to wait for the Vampire 500 for that.

On the other hand, there's no good reason a Raspberry Pi couldn't be used to provide an older Amiga with ethernet and storage, and perhaps some other services. With 17 or so GPIO, it wouldn't be ideal to use a Pi as a Zorro expansion because it'd take a bit of circuitry to multiplex the address and data busses for the GPIO, but it's possible.

What's within the realm of possibility with just a handful of wires is a parallel port to Raspberry Pi connection for ethernet and storage. One would just have to adapt some of the drivers which already exist in Aminet to the Pi.

I've used Pis and other small computers (PogoPlugs, Beaglebones) to speed up compiling on retrocomputers. Right now a faster machine is helping my m68060 Amiga 1200 compile binary packages for NetBSD. If we had newer toolchain tools for AmigaDOS, some of this might be applicable.

https://hackaday.io/project/218-speed-up-pkgsrc-on-retrocomputers

[QuikSanz]

I was thinking about if you could route a Pi3 thru a vampire and be able to use 3.9 and Linux at the same time.

[nicholas]

I've always dreamed of an x86 CPU running nothing but a 68k emulator sitting on a CPU accelerator board that appears to the Amiga as a real 68k.

It's far beyond my capabilities though so I sit in hope that one day a genius will have the same idea and make one.

[psxphill]

I was thinking about if you could route a Pi3 thru a vampire and be able to use 3.9 and Linux at the same time.

You can have 3.9 and Linux at the same time if the Pi isn't connected to the a500 at all.

Or you could run Linux on the a500.

[QuikSanz]

Linux on a 68k? Old Linux is of no interest to me, something a bit faster and more productive is what I had in mind.

[kolla]

An obvious problem is voltage differences, the Amiga using 5V and the Pi using 3.3V, but that can be worked around. A general interface adapter that plugs between Amiga parallel port and RPi, offering a PLIP-like service (for example like PlipBox, only connected to a bridge interface on the Pi) on which you can run netfilesystem, mounting directories etc on the Pi. A bonus could behaving console on the Pi on the serial port

[ChuckT]

The Raspberry Pi doesn't have enough pins, nor the speed to react to those pins, to replace an m68000 processor. You'll just have to wait for the Vampire 500 for that.

On the other hand, there's no good reason a Raspberry Pi couldn't be used to provide an older Amiga with ethernet and storage, and perhaps some other services. With 17 or so GPIO, it wouldn't be ideal to use a Pi as a Zorro expansion because it'd take a bit of circuitry to multiplex the address and data busses for the GPIO, but it's possible.

What's within the realm of possibility with just a handful of wires is a parallel port to Raspberry Pi connection for ethernet and storage. One would just have to adapt some of the drivers which already exist in Aminet to the Pi.

I've used Pis and other small computers (PogoPlugs, Beaglebones) to speed up compiling on retrocomputers. Right now a faster machine is helping my m68060 Amiga 1200 compile binary packages for NetBSD. If we had newer toolchain tools for AmigaDOS, some of this might be applicable.

https://hackaday.io/project/218-speed-up-pkgsrc-on-retrocomputers

Correct.  I'd probably use an ARM chip or a CPLD.
In this game, you pretty much have to own a $400 Oscilloscope, have a circuit board drawing program like Diptrace, be able to read a schematic, know basic electronics and know voltages.  On top of that, you have to know how to program to interface with that port which is another ballgame.

[Gulliver]

I would just use a null modem connection. It is slow but pretty inexpensive to add to the Pi an RS-232 port.

On the software side, I would use Happiga and either a Remote Desktop Client and XRD on linux, or just Siamese 2.5.

[psxphill]

Linux on a 68k? Old Linux is of no interest to me, something a bit faster and more productive is what I had in mind.

Port a modern Linux to 68k and run it on Vampire.

Rpi isn't particularly fast and connecting it to an a500 would not make it better.

An Arm chip on an a500 expansion is slightly more interesting, although it would have no software so a vampire is much better.

[kolla]

Port a modern Linux to 68k and run it on Vampire.

Rpi isn't particularly fast and connecting it to an a500 would not make it better.

An Arm chip on an a500 expansion is slightly more interesting, although it would have no software so a vampire is much better.

Modern Linux already runs on m68k, the problem is that Apollo Core is not a supported architecture, and most likely never will be. Anyways, a rPi runs in circles around Apollo core, so I don't see your point.

[psxphill]

Anyways, a rPi runs in circles around Apollo core, so I don't see your point.

Use an rPi then, but it makes zero sense trying to combine it with an a500. What are you going to do hook the a500 up with rs232? That sounds modern (http://amiga.resource.cx/exp/siamese).

You could use an Ethernet card on your a500, but you're still not really integrating the two together. You've just created a LAN.

An RDP server for Amiga would be interesting as you could use the rPi for video output, but you could also use a PC. You could also run an X server on the a500 and connect the rPi to it, so you can output Linux software to 4 colour ECS. It might be fun for a few minutes, although it will be really slow (even slower if you run 8 or 16 colour). At least the software for that has been around for 20 years already.

Hopefully as some point Apollo will wake up and support the 060 MMU so you can use Linux too (well you can use Linux without an MMU but some things don't work https://www.kernel.org/doc/Documentation/nommu-mmap.txt)

I hope that eventually Vampire supports Wifi somehow.

[Zardoz]

guys, it can be done. but it's slow as you would have to use the a500 serial port that is limited to 19200 bps speeds. basicly you set up ppp connection on the rpi you would need a USB2Serial cable and a null modem cable then set up a ppp between them.

might be a youtube on it...

*ADDED*

https://www.youtube.com/watch?v=fEonOb5SkEg
http://jmp.no/blog/cheap-overkill-amiga-network-adapter
http://www.amiga.org/forums/showthread.php?t=67150