rasz_pl wrote on 2022-03-02, 18:48:

pi yes, arduino no unless all you want is HID or serial […]
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Shreddoc wrote on 2022-03-02, 06:24:

by way of devices like the Pi and Arduino.

pi yes, arduino no unless all you want is HID or serial

Shreddoc wrote on 2022-03-02, 06:24:

So, the USB4VC an already working proof-of-concept that a generalised "USB Host -> Protocol Convert To Legacy"

at that point you can just remove PC altogether and run dosbox on the pi 😀

Shreddoc wrote on 2022-03-02, 06:24:

Again, not in the specific ISA-card sense, but knowledge of ISA is not what is holding anything back here.

Its not "knowledge of ISA" that is the problem, but strict bus timing requirements forcing use of FPGA unless you are willing to write software support from scratch (then dual ported SRAM will suffice)

There is a difference between:

-connecting PI in some standard way like serial/PS2/keyboard/gameport and emulating standard devices. This is easy and pi is huge overkill.

-connecting PI in non standard way like LPT/dual ported ram. This requires custom software on the PC, devices interfaced thru PI wont "just work" in DOS programs. For example http://www.smbaker.com/raspberry-pi-virtual-f … -xtat-computers

-fully emulating devices on the ISA Bus level (register/memory map) transparently to the PC and DOS programs.

We are discussing in the past few posts digger's suggestion - to paraphrase: "An intelligent ISA USB card that exposes the USB devices you plug into its backplate as typical DOS compatible devices". You seem to be claiming his idea is not technically feasible. If that is the case, then so be it. I'm not the person to say so.

Yes you could just use Dosbox on a Pi instead, as you jokingly noted. However, naturally, if the goal is to interface new gear with old computers, then simply playing on a Pi instead is not meeting many of the project's goal requirements. 😉

In any case, the USB4VC, despite it's limitations, still begins to illustrate the true complexity involved in any such project. And that's just for controllers into ports. Extrapolate that complexity out to digger's idea of doing similar for ISA soundcards ... and I think we both agree that would be a rabbit hole a mile wide.

This is no denigration of having the idea - it's only through discussions like this that we as a community whittle our way towards valid conclusions.

Shreddoc wrote on 2022-03-02, 19:59:

We are discussing in the past few posts digger's suggestion - to paraphrase: "An intelligent ISA USB card that exposes the USB devices you plug into its backplate as typical DOS compatible devices". You seem to be claiming his idea is not technically feasible.

Not infeasible, there is a misalignment of complexity expectations. When you have low level SB/Covox/WSS/Adlib Gold/PAS implemented in FPGA/CPLD the process of actually outputting audio is the trivial bit requiring either 2 GPIO pin pins, some PWM and a filter or $1 codec chip (ES9023). Involving USB in this last step creates needless complications. mcu able to run as USB host and usb audio stack are serious business unless you just throw $pi$ at it ending up spending >$50 for something $1 ES9023 does better.

rasz_pl wrote on 2022-03-02, 23:07:

Shreddoc wrote on 2022-03-02, 19:59:

We are discussing in the past few posts digger's suggestion - to paraphrase: "An intelligent ISA USB card that exposes the USB devices you plug into its backplate as typical DOS compatible devices". You seem to be claiming his idea is not technically feasible.

Not infeasible, there is a misalignment of complexity expectations. When you have low level SB/Covox/WSS/Adlib Gold/PAS implemented in FPGA/CPLD the process of actually outputting audio is the trivial bit requiring either 2 GPIO pin pins, some PWM and a filter or $1 codec chip (ES9023). Involving USB in this last step creates needless complications. mcu able to run as USB host and usb audio stack are serious business unless you just throw $pi$ at it ending up spending >$50 for something $1 ES9023 does better.

We agree that the sound card aspect is difficult.

Anyway, when thinking about an all-in-one device, I prefer the Linux-y philosophy of "do one thing, do it well". Rather than a device trying to immediately be Everything At Once, I would prefer to see separate devices developed first, to show competence, and gain efficiency (of cost, and technicality). Then, combining into Swiss Army Knife Do-Everything version can come later, and is conceptually simple once the separate functions are mastered.

Now massive ROMs are cheap. could you just take envelope parameters as an address offset and it kinda spits out the right pattern to sum to a generic waveform, resulting in something that does FM/adlib with a large ROM, adders, bit of logic and a big old pile of resistors DAC. Kind of nearly wavetable but not. ROMs are a bit like a dumber form of FPGA if you abuse them right.

BitWrangler wrote on 2022-03-03, 01:45:

Now massive ROMs are cheap. could you just take envelope parameters as an address offset and it kinda spits out the right pattern to sum to a generic waveform, resulting in something that does FM/adlib with a large ROM, adders, bit of logic and a big old pile of resistors DAC. Kind of nearly wavetable but not. ROMs are a bit like a dumber form of FPGA if you abuse them right.

You can "reduce" anything to a (in)finite state machine.

The other salient question is "who shall be decompiling all the existing popular soundcards, then programming FPGA versions of them?".

(frankly unnecessary sarcasm follows!) We should cut the long list down to a shorter few candidates and volunteers. :p

Shreddoc wrote on 2022-03-03, 02:16:

The other salient question is "who shall be decompiling all the existing popular soundcards, then programming FPGA versions of them?".

There already are a few open source SB reimplementations, with BLASTERBOARD BLASTERBOARD : A new SB 2.0-compatible ISA sound card being much better than the original.

Hi,

I was going to start a similar thread but found this instead.

A few days ago I finished setting up my Amiga 500 with Pistorm and Emu68 and I was amazed from the quality of the HDMI video output, if compared to any old pc with vga graphics I own.

So if somebody have in their mind anything similar for a motherboard with ISA slots, I'm interested!
I have many AT motherboards laying around, finding more suitable cases for them is an exhausting effort that means spending loads of money and cluttering up the house.
I'd prefer something that would sit horizontally on the ISA slots (and VLB if present), offering HDMI graphics, SB sound, a network interface,disk i/o and UART if necessary
Something like the ZZ9000 but for ISA and not upright. Taking advantage from the bare metal raw power of a raspberry pi, similarly to emu68.
No need for a standard AT case anymore, everything can be fitted into a smaller 3d printed case that makes a nice appearance in a living room.
This kind of adapter would be good for motherboards with ISA/VLBUS slots, so I think another shall be made, with more advanced features, for those with PCI slots.

So, how do you like it?
Also, what is a cool name that could be given to these sawed-off retro systems?

Somebody's relevant project.

https://hackaday.com/2022/11/13/emulate-any-i … pi-and-an-fpga/

https://github.com/eigenco/frankenpi

From the github wrote:

This is an experimental project to connect Raspberry Pi with the help of cheap Cyclone IV FPGA board to 8-bit ISA bus to act as […]
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This is an experimental project to connect Raspberry Pi with the help of cheap Cyclone IV FPGA board to 8-bit ISA bus to act as multiple different devices.

What is currently implemented (to some degree), i.e. PC can access through ISA

• Mass storage access from a file on the Raspberry Pi (written sectors are flushed every 2 seconds by default)
• Adlib output to optical SPDIF
• Sound Blaster 8-bit mono with DMA and IRQ (basic functions only), output to optical SPDIF
• Gravis Ultrasound (basic wavetable only), output to optical SPDIF
• Roland MT-32 (UART only), output to optical SPDIF
• USB mouse plugged into the Raspberry Pi will appear as a kind of serial mouse in DOS, custom ctmouse driver is provided (start with /v)
• Boot from custom TVGA9000i VGABIOS, i.e. no other devices are required to be present in the ISA bus besides FrakenPi and VGA-adapter

In addition to the PicoGUS project, of course, which is already under discussion in it's own Vogons thread.

The first time I heard about such an idea was here: The one sound card to rule them all

Many soundcards on one board is quite appealing to me, graphics-cards on the ISA bus not so much.

A good Soundblaster with RAM, GUS, MT32 and SC55 is hard to get and pretty expensive. And then there's stuff that only supports SB 2.0 or SB Pro or whatever. Replacing all this with one solution is the only way for many people to experience it at all.

Compared to this, ISA-VGA cards are cheap and easy to get. And I wouldn't use ISA VGA on anything >=486