Question about USB on the minimig

[techie]

So Recently I have been going through some of the Minimig threads and I've noticed that whenever the topic of adding USB to the Minimig is brought up people seem to jump to the conclusion that it would be impossible to add. Now this really made me start to ask the question -

Just what really is preventing us from adding this feature into future revisions?

A lot of people seem to say it's the 68000 cpu that is the biggest hurdle but according to an Article entitled
'USB Stack for AmigaOS 1.3' in Amiga Future (NR.67) there  already is a solution for running USB on 68000 equipped Amiga's. Now granted this USB stack does not support the one thing I'm really interested in (i.e. USB joysticks/gamepads) but it does at least appear (to me anyway) to be a step in the right direction.

Now don't get me wrong here, I'm not assuming that we could just tack this stack onto the MiniMig and BOOM instantly have access to USB devices. But I do think it would be helpful if people could just explain to us non-hardware people just what else is stopping us from having USB in future designs?

Edit:
Please Note: I do understand that the current design of the MiniMig was not built with USB in mind but I am curious about the possibility in future versions.

Edit Edit:
Also Note: I'm also aware that some people don't feel that USB is worth the effort of adding. Now while I respect that some people feel this way (and I can sort of understand the reasons behind this opinion) I still think it's important for us to at least discuss the possibility of adding USB without necessarily delving into the debate of whether or not it is worth adding.

 

[techie]

Piru wrote:
IMO USB isn't suitable for Minimig, but lets consider it:

To be of any use the USB-stack would need to run outside of the emulation in the first place (this is kind of obvious if you think about it: How would you go on about launching the USB-stack if you're booting from a game floppy? You obviously want to be able to use the keyboard and mouse in games...)

IMO the only sensible way would be to have some sort of independent USB-on-chip solution that'd give PS2-like signals easily, without actual need to have custom USB-stack. That'd be "easy" (relatively speaking) to wire to the current Minimig design.

However, once the USB is outside of the emulation itself, it means that the running system will not get any real benefits from the USB in the first place (actually, it won't see USB at all, just keyboard and mouse/joystick thru the CIA/Custom registers).

In fact, you'd get much of the same (except amiga joystick) by connecting some external USB-to-PS2 bridge to current minimig.

Okay so let's consider this option for a moment.

The benefits:
1) Access to a wide variety of USB based joysticks.
- Which could also include Amiga joysticks too if you happen to convert them to USB with something like this RetroUSB Atair/Commodore Adaptor Kit

2) Access to multiple USB Mice for two player games (examples: Marble Madness, Lemmings, etc...)

3) Access to USB Keyboards and Mice.


The Downside:
1) Most USB Keyboards and Mice can already be converted to PS/2 so there really is little to gain.

2) Still no access to USB storage devices
- To me this really isn't a big loss as since we already have an SD Card reader built into the MiniMig. Plus it has been stated before that EIDE could be added to the MiniMig which would also give us access to harddrives and other storage media.

3) No Access to other USB technologies (i.e. Printers, Camera's, Misc devices...)
- Again to me this really isn't a big loss either since there is little reason to run these devices on the MiniMig in the first place.


Hmm...so the only REAL benefit from this particular solution would seem to be:

A) USB joysticks
B) Multiple Mice (which I must say I would LOVE to see again but that's just me  :-) )

Admittedly this doesn't seem to make a strong case for adding USB to the MiniMig (using this solution anyway). Can anyone else think of reasons I have missed for Adding USB to the MiniMig design? Or other solutions which could bring added benefits?

[techie]

downix wrote:
Alright, let's crunch the numbers:

USB is a CPU-driven, not DMA driven, system.  That means for every batch call, the CPU must be utilized.

For a single mouse, you will, at peak, utilize 12Mbps, roughly 1.5MB/sec.  Now, the Amigas RAM speed is only 7MB/sec.  So, for a single, solitairy mouse, you'd be tying up 40% of RAM access.... just imagine adding a keyboard.

Sorry I'm probably just being Thick here but if this is the case then I have to ask; How does the Anaiis USB stack work then???  :-?
Because it claims to be working on a pretty much stock Amiga 2000 with ZorroII Highway USB and 68000 processor (7.14 Mhz).
(http://aminet.net/package/driver/other/anaiis)

Hattig wrote:
If you eventual point in all this is that you want to use a USB gamepad to play Speedball 2, then this is nigh-on impossible.

Yes, you can attach a USB port to a 68000, the rest of the system is just code. However due to the nature of the software part of USB, you would need to run what is probably quite a heavy duty bit of software alongside the game that already probably uses >90% of the 68000's available power. Alongside that you would need to map the USB gamepad input into standard Amiga joystick inputs. And then you'd realize that Amiga games boot from ADFs on the MiniMig, and that there's no way to stick the USB stuff into that.

The only way it could be done would be to have a second CPU that runs the USB stack transparently, and also does the mappings to classic Amiga hardware transparently. Here, of course, you start seeing the level of work that would be required.

Agreed, this does sound like it would undoubtedly be a project in and of itself but that doesn't necessarily mean it's impossible (just improbable :-))

So my next question would be; would the Vinculum solution that jkonstan mentioned make such a project any easier? If so what would this solution do to the overall cost of the minimig?

[techie]

JimS wrote:

techie wrote:
So my next question would be; would the Vinculum solution that jkonstan mentioned make such a project any easier? If so what would this solution do to the overall cost of the minimig?

Yes, the Vinculum would make things easier. You can buy an assembled board from them for a reasonable price. They even have one with a MP3 decoder chip for playing music. So all you'd need to do is make a cable..... oh yeah.... and write the software. ;-)

I'm sure it wouldn't be just plug'n play but it could be an asset.

Personally, I'm beginning to more into the "USB is pointless" camp. It would be cheaper to just use the SD cards... after all to use a minimig you'll need to put an SD card interface in your PC....

Which is probably right if all you wanted out of USB is access to storage devices but if you also wanted to use USB joysticks and mice then access to SD cards doesn't really help :roll:



More and more it sounds to me like there are really two groups of people who are asking for USB 1) You have people who want access to USB Mass Storage devices and other high tech gadgetry and 2)You have people who just want access to USB joysticks, mice, keyboards. Now I think it's safe to say that it is looking more and more unlikely that the first group will ever see this functionality without redesigning the MiniMig completely but what about the second group?

What if we only focused on making USB joysticks, mice (2x), and keyboards compatible with the minimig for classic gaming? Would that help reduce the complexity of this sort of project and would that be enough to satisfy most people when it comes to USB?  

 

[techie]

Belial6 wrote:
I still don't get what the huge focus is for using USB for classic gaming.  I would want to see USB for use from the Workbench.  I'm perfectly happy using a 9-pin joystick and adfs (hopefully, someone will eventually make an open IPF replacement) for gaming.

I want USB to be able to hook up a scanner, or drawing tablet, or mp3 player, or any other device I haven't thought of.  The explanation I keep hearing for why this can't/shouldn't be done is that you can't use it to replace the joysticks and floppy drives for classic gaming.

So, my question is, given that we have already established that the processor speed is not an issue due to solutions with there own built in processor, what prevents USB from working from Workbench?

I guess the focus on USB for classic gaming is partially because people like to have choices when it comes to input devices. I for one would like to have the option of using either a classic joystick or a USB gamepad to play different Amiga games.

There's also the fact that classic controllers simply won't last forever. I have at least two joystick in my apartment which have simply stopped working on me because the cords got a little mangled during my last move (the box they were in got crunched a bit :S). So having access to USB joysticks and mice would give me a lot more options.

I also like the idea of being able to use two mice at the same time in games like lemmings and marble madness without having to resort to using my Amiga 1000 angle mouse + a PS/2 mouse :-(  

[techie]

Hattig wrote:

The whole point is that (2) is really difficult, requires a lot of extra hardware and why not just use PS2 keyboards, mice and 9-pin joysticks?

Like I said before, partly because 9-pin joysticks won't last forever and also because it doesn't let you use multiple PS/2 mice for those few games that have two player mice support.

I get the whole PS/2 keyboards and mice argument and I kind of agree since there are already adapters that let you hookup USB mice and keyboards to PS/2 but it still doesn't solve the joystick problem.

(1) is a lot more possible, if you just want to run USB within Workbench. It might be slow given the 68k, but once you have the software stack, you can attach whatever USB devices you want - including keyboards, mice, gamepads (they just won't work in a non-AmigaOS environment).

Wait doesn't this solution STILL require "a lot of extra hardware" to implement as well? Wouldn't this also require a higher end CPU to be integrated to really get anything out of all those high end peripherals?

Sorry it still sounds to me like option two would be easier (albeit a lot of work) to implement in the current minimig design.

little wrote:

If people really want to use their USB joysticks with 16bit era machines then the solution is to make an usb to de-9, this could also of interest users of msx, commodore 64, sega genesis, etc.

While I would still prefer an on board solution this type of adapter would probably be enough to satisfy people like me as long is it could be used with both USB joysticks and mice.

[techie]

koaftder wrote:
USB on minimig 1, it's not going to happen. ps2 devices are cheap and easy to obtain. Who cares?

If you want USB on minimig 1, talking about it is useless, you will have to do it your self or perhaps hold out for minimig 2.

Which is pretty much what I said in my first post:

techie wrote:
Edit:
Please Note: I do understand that the current design of the MiniMig was not built with USB in mind but I am curious about the possibility in future versions.  

little wrote:
As I have said before, I think an USB to DE-9 adapter for joystick and mice would suffice, but there is another reason for an OS transparent USB interface. It would enable transparent emulation of the CDTV/A570 and later on it would be posible to create verilog code to run other CD-ROM/68000 based hardware. This will be beyond the capacities of minimig 1, but I think we all agree USB 1.1 is all about minimig 2.0 :-)

I think we're on the same page here I agree that such an adapter would suffice for now (provided it can work with both Joysticks and Mice). But like you say it would still be nice to have transparent onboard USB in the future as it would open up more possibilities.

[techie]

So what can we conclude from all this?

1) That USB for classic gaming (i.e. USB joysticks and Mice in games only) is probably not going to happen without some sort of external adapter (Most likely in the form of USB to 9pin adapter) to do the work.

and 2) USB for a Harddrive/Flashdrive based MiniMig running AmigaOS is possible but impractical :-(

Does that about sum things up :-?

[techie]

Gilloo wrote:

techie wrote:
Sorry I'm probably just being Thick here but if this is the case then I have to ask; How does the Anaiis USB stack work then???  :-?
Because it claims to be working on a pretty much stock Amiga 2000 with ZorroII Highway USB and 68000 processor (7.14 Mhz).
(http://aminet.net/package/driver/other/anaiis)

Hello. As you see, I'm the author of this *fabulous* stack... ;-)
ANAIIS is nothing without the uhc124 die (TransDimension), and the help of Michael Boehmer (The conceptor of Subway and Highway).
This non-PCI die can easily manage transactions between the 68000 and the usb world. The only limitation of ANAIIS is the lack of isochronous support (can't use audio, video,...) but a simple 68000 can't manage interrupt each millisecond, and for my own usage, I don't use these peripherals on my 'miga: only hub, mouse, keyboard, printer. For games, it's better to use the original gameport. This stack seem to be closed and limited: normal still in dev, and I'have no time to improve it (maybe a Subway version will be available *soon*)!

On Minimig, it will be good to implement this kind of die (like uhc124, non PCI chip...), and map register with a PIC (or other way), to keep compatibility with original hardware.

Thank you very much for your input :-)
So I guess the only hope for USB joysticks is if someone out there creates a USB to 9-Pin adapter but on the plus side at least it sound like USB mouse and keyboard support is feasible (if only from within Amiga OS).