I thought I would start a new thread to prevent the other one becoming too cluttered.

I am not aware of the full potential of this device and was wondering if someone (or Gideon who is very busy making my unit ) could explain.

Would I be able to "swap-out" the C64s memory? For example, if I was writing an assembly program and decided suddenly that I would like to play a game. Could I "freeze" what I was doing and swap-in a game?

Is loading from the device done at turbo / warp speed or is it at the standard 1541 speed?

Will I be able to load multi-load games from a .d64 file? Will the various load stages be done a turbo / standard speed?

Will this unit be able to completely replace a 1541 or are still some things that the 1541 could do that this can't?

If someone could give some more examples of what this unit can do I would appreciate it. From what I have picked-up in various places, this unit seems to be what most people have been looking for. I, myself am looking to be able to store my existing floppies on this device and perhaps retire my existing 1541s.

Ok Borat, here it goes!

This is currently not a feature of the 1541 Ultimate. However, the cart also implements Action Replay, or The Final Cartridge III. I believe that these cartridges have the ability to save the C64 state to a disk, for which you can use the virtual 1541 of the cart.

This depends on the loader that you use. It is a 1541, so it behaves exactly like one. You could use the warp loader of the Action Replay or FC-III in combination with the 1541 Ultimate as well.

Yes, you can. You can just select a .D64 file, and mount it in the 'drive'. Then you can just load the multiloader game as you are used to with a normal drive. Any particular loader-program that is part of the game will also work.

Basically all functions of the 1541 also work on the 1541 Ultimate, even including some programs that make "drive music". However, when it comes to saving data back from the floppy onto the SD-card, there are some limitations, because the software is currently only able to understand "standard" tracks. Similarly, only standard .D64 images can be loaded. Currently, the cart does not support .G64 (GCR encoded) files, but when I have the time, I'll see what I can do to implement this.

Excellent! I am sure that the 1541 Ultimate does a lot of what you're looking for. I am not sure on how to describe all features, but these are a few:
1. complete 1541 virtualization
2. cartridge emulation: Action Replay + FC-III
3. user friendly disk-selection menu
4. FAT/FAT32 SD-cards (up to 2GB, no SDHC support yet)
5. Long filenames
6. Browsing inside .D64 and .T64 files
7. DMA-load (ultra fast!) of single files from SD / .D64 / .T64
8. emulated drive sounds (tracking and motor hum)
9. 'direct' access to the SD-card by means of a second device on the IEC bus (try load"$",12 [or whatever address you configured for it] hehe..)

and for the plus version... REU (up to 16 MB).

...what else?

Gideon

[removed the second post]

Thanks for the info Gideon. Really appreciate it.

If I can think of any more questions I'll post them. When do you expect production and testing to be complete? I believe the end of February was mentioned somewhere?

Thanks again.

How? - I mean, in which fashion is the audio output? - Line Out? Piezo? Speaker Output?

And can we disable it if we don;t like it ?

Mark

You can disable any part of the cartrige. The output is just a line-out kind of jack plug. You could attach it to a speakerset if you want.

What? Wait! Does it emulate the sounds from a 1541 too???

Yup, of course! 100% compatibility, right?

The 1541U seems very interesting and I am tempted to buy one.

I have read that the 1541U does not work in a cartridge expander? Is this true?

I read that there are some limitations to writing to the SD card. What are these limitations? Will I be able to save my highscore in a game? Can I save a text document that I have written on the C64 using some word processor? Can I save a program I have written on the C64?

90% of games and demos should work. What does not work? Will it be possible to make the remaining 10% work or is there a limit in the technology?

Or to EXT_IN on the SID

After this bit of information I think that we can safely assume that you've thought about everything

Great!Well, the first prototype doesn't work with all expanders. The second (final?) version might work in more expanders, but.. as I can't guarantee that it will work in all expanders (just because I don't know all expanders), it is safe to assume that it doesn't. You might be lucky.
The limitations are related to the format of the tracks and sectors. As long as the standard format is used, the cart will be able to save write data back to the .D64 image. This is the case in 99% of the cases, I think. So yes, you can save the highscore in a game, yes you can save a text document, and yes, you can save programs that you've written on the C64. For the latter two, you even have two options; you either save them to the 1541 drive (to the mounted .D64 image), or directly to the SD-card through the software-IEC; creating a separate file on the SD-card (in any directory).As far as I can oversee, there is no limit in the technology. What is not guaranteed to work as of now are loaders that make use of illegal opcodes in the loader-code; with the exception of opcode $CB. The latter turned out to be used in the loader of the Wild Bunch. After fixing the cpu this demo also worked. More opcodes might need fixing, but it is not a limitation of the used technology.

What issues does it have with expansions? Is it a buffering issue or just IO address conflicts?

Also brings up a question, AR/FCIII are not compatible with REU due to IO conflicts, which is a problem with a device which implements both speeder cart and REU. RetroReplay works fine with REU. Have you tested with a Retro Replay image?

On the subject of RR, how hard would it be to implement a clockport on U1541? Cart expanders may never be needed again...

Does it also go out of alignment?