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Ultimate II+ and tape queries

  • ,Hi all,


    A few weeks ago (in another thread) I enquired about compatibility of the Pi1541 & Epyx Fastload cartridge with the MEGA65, as I thought it'd be a good idea to get such a thing to make access to existing software easier.


    However, for various reasons I haven't yet got one. This is partly because of availability: I want one in a plastic case, and they're currently unavailable, with the only options seemingly being bare circuit boards.


    In the meantime, I've also discovered the existence of the Ultimate II+ cartridge. Although it's a lot more expensive than the Pi1541 options, it appears to be a really good product. It comes in a nice plastic cartridge case and appears to do all that I want, and a great deal more too. I've a good mind to get myself one, as it seems like a very futureproof option, even if I don't need all its facilities.


    Anyway, it again leaves me a with a couple of questions…


    1. Will the Ultimate II+ cartridge work OK in the MEGA65, at least in C64 mode? I appreciate that there may be some features that won't work, but I'm primarily interested in it as a 1541 drive emulator. I've been in touch with the guy who designed the Ultimate II+ and he believes it will work OK, but he doesn't have direct experience of the MEGA65, so it'd be useful to know if anyone has any experience, and/or whether there are any problems I should know about. Again, the Ultimate II+ does a great deal and I won't need all of its facilities, but I'd like to use the 1541 drive emulation at the very least, and I'd like to be sure that attempting to use the Ultimate II+ with my MEGA65 won't do any damage to my MEGA65.


    2. The Ultimate II+ offers some form of tape compatibility, and this raises a whole new area of uncertainty! The only time I've used tapes with a Commodore machine, personally, was on the very first computer I ever used, a PET 2001 Series with inbuilt tape drive. As far as I know, the MEGA65 doesn't even have a port to connect a physical tape drive. Is that right? As I understand it, the tape drive needs its own dedicated port and doesn't use the serial port that other peripherals (like the 1541, I think) use. Is that correct? Or is there some way that I'm unaware of to connect a Commodore tape drive to a MEGA65?


    3. If it's true that the MEGA65 can't interface to a cassette drive, does it still contain the necessary software support to load tapes? I.e. the Ultimate II+ also contains a tape emulator, and can therefore play .tap/.t64 files into the machine as though it were loading from tape. Would this work on the MEGA65 (even if only in C64 mode)?


    Point 2 isn't very important to me as I don't particularly wish to connect a physical cassette drive to the MEGA65. However, the ability to load virtual tapes (point 3) would be desirable.


    Sorry for the 'noob' questions, but my experience of Commodore hardware is pretty limited, so matters of cartridges, tapes etc. are completely outside my direct experience.


    Thanks!

  • ... does it still contain the necessary software support to load tapes?

    I have no MEGA65 or DevKit for testing it, but the C65 part and also the C64 part in the C65 ROM doesn't support tape functions.


    In the C64 kernel part, you can read in the sourcecode:

    So I think a solution for tape handling needs some own routines to work. So it wouldn't be "too easy" to use tape images.

  • I've been in touch with the guy who designed the Ultimate II+

    That's Gideon, Yes theoretically the 1541UII+ should work, but it is not supported yet.

    It is on our todo list to finalize the cartridge port.

    For the time being you can use the SD2IEC or a PI1541 to be able to use D64 images.

    As far as I know, the MEGA65 doesn't even have a port to connect a physical tape drive. Is that right?

    The C65 (and the MEGA65) never had a cassette port. iirc the Tape routine was removed from the C64 Kernel for the C65. So in principle it could be possible to re-implement the cassette support, the MEGA65 is prepared for it, but this is planned for the future, after the MEGA65 has been released.

    the Ultimate II+ also contains a tape emulator, and can therefore play .tap/.t64 files into the machine as though it were loading from tape

    The 1541UII requires a Datassette port for that feature (.tap), since you connect a cable from the 1541UII to that port to "simulate" a Datasette. Like i said, the C65 never had a Datasette port...

    supporting .t64 should be easier to implement.

  • Snoopy and adtbm: thanks very much for your responses – very helpful, and much appreciated.

    That's Gideon, Yes theoretically the 1541UII+ should work, but it is not supported yet.

    It is on our todo list to finalize the cartridge port.

    For the time being you can use the SD2IEC or a PI1541 to be able to use D64 images.

    Yes, Gideon. I must say, I like the sound of his Ultimate II+ cartridge: it seems to be an excellent peripheral that does a lot. I'm very inclined to buy one, even if it won't work immediately on the MEGA65. I think it'll be a good thing to have for the future, assuming it'll work eventually once the cartridge port support is finalised.

    The C65 (and the MEGA65) never had a cassette port. iirc the Tape routine was removed from the C64 Kernel for the C65. So in principle it could be possible to re-implement the cassette support, the MEGA65 is prepared for it, but this is planned for the future, after the MEGA65 has been released.

    This is what I was afraid of: I was pretty sure that a cassette couldn't be added to the MEGA65, and if the hardware support is gone, I feared the software support might be gone too… as, evidently, it is.


    That's a pity, because if the MEGA65 is indeed supposed to be highly compatible with the C64, it ought (in theory) to be compatible with its tapes. Not being able to use physical tapes probably isn't a big deal, but it would certainly be nice if it were able to load tape images (.tap/.t64 – I'm not certain of the difference) as files on the SD card.


    This is one area in which I feel quite spoilt as a ZX Spectrum Next user… because the Next has excellent support for a wide range of file formats, and you can have them in a hierarchically organised structure on the SD card. Indeed, you can do that with the ZX-Uno core on the MEGA65 as well, of course; it's just that the Next does a bit more than the Uno, and has a nicer file browser. For example, there's support for disk images if you want them, though the Spectrum only got disks late in its life, so they're much less important than tapes. But with .tap tape files, you can open them and either load them 'authentically' (simulating the original experience) or load them instantly into memory. As for .tzx tape format, which is an archival format designed for emulators, if you have the optional Raspberry Pi fitted, you can pipe .tzx files over to the Pi and have it play them back through the Spectrum's audio circuitry so that it's exactly like physically playing in a tape (though you can accelerate it up to 28MHz for super-fast loading).


    I mention this simply for contrast, because when I first got my MEGA65 DevKit, I was a little surprised that it didn't have more inbuilt support for loading image files. Indeed, given my limited knowledge of Commodore hardware, I've been a little surprised by the extent to which it seems encumbered with some not always terribly well designed storage peripherals. I was aware that the Commodore machines had a relatively slow tape interface (this stands in contrast to the Spectrum's tape handling, which – despite its negative reputation – was actually the fastest and most reliable of any 8-bit system) – but I hadn't known that support for it had been removed from some machines. The extreme slowness of the 1541 disk drive is well known, of course, but I hadn't realised that there were mutual incompatible disk drives that each require their own image file format. And I haven't yet got to the bottom of what the Epyx Fastloader actually does.

    Anyway, it's just interesting to see how different systems handled different things. My favourite 8-bit system in terms of storage is still Acorn (BBC): its cassette system wasn't as fast and reliable as the Spectrum's but it was still very good, and was supported on all the 8-bit machines. And its disk drive support was superb: pretty much standard from the earliest days and it worked brilliantly; you just bought your choice of drive(s) from any of multiple manufacturers, the disks were all compatible, you had a choice of filing system, and the disks were extremely fast and efficient. Great system.

    So, mass storage seems to be an area in which Commodore could have done rather better than it did. Still, I suppose it makes life more interesting! :-)

    As far as the MEGA65 is concerned, it would be really nice if, over the long term, it could gain support for loading all the various common image formats (i.e. .d64, .d81, .t64, .tap; any others…?) off its internal SD cards – and allow them to be organised in hierarchical folders, as can be done on Spectrum machines with SD cards.


    Anyway, thanks for the answers. This is all very interesting and useful to know.

  • 1. I’m afraid the Ultimate II+ might be problematic with native MEGA65 software, as it does not know about VIC-IV video modes, so it might be unable to display it’s menu and restore the previous video settings. I could already see the IEC part of this cartridge working, though. And keep in mind, that 1541 drive simulation using images on SD card is planned for MEGA65 at some point. D81 images can already be mounted to the internal C65 drive controller.


    2. True, the C65 ROM has tape routines removed. Bringing them back for C64 mode can be challenging, I’m not sure how much space is left in the C64 part of the ROM. One option for the user could be to switch the ROM set to original C64 one. AFAIK ROM switching is currently being worked on by someone.


    On the other hand, Open ROMs already has code for loading software from tape (normal and TurboTape 64, with file formad autodetection and a built-in head alignment tool) - but without saving and using data files (OPEN, GET#, etc. mechanisms won’t work). See

    [External Media: https://vimeo.com/466214042]
    and
    [External Media: https://vimeo.com/425935795]
    , you can test it within in the C64 emulator here https://dirkwhoffmann.github.io/virtualc64web/ .
    These functionalities are, of course, not tested on MEGA65 yet, due to lack of hardware.

  • Not only C65 had removed cassette routines (from C64 mode as well) but it's true for hardware level as well. The C64's "CPU I/O port" (realized by VIC-III on C65 for real, but it does not matter too much here) on C65 does not even have functional bits for tape functions, only the lower 3 bits works, needed for memory banking. Surely, on MEGA65 - in theory - it would be possible to "re-add" them, and then the software support as well in some form ... I guess. :)