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  1. otacon14112's Avatar
    Ok, nice. I have just always used floppy disks instead. This would be really handy.
  2. Chuck(G)'s Avatar
    Suppose you have a library of floppy images; put them on a USB stick and use the Gotek gizmo in place of a floppy drive and never have to deal with the spinning rust again.

    Not every computer has a hard drive or network capability.
  3. otacon14112's Avatar
    Interesting! But if I may ask, what is a floppy emulator used for? I mean, it obviously emulates floppy disks, but how would you use it?
  4. Chuck(G)'s Avatar
    5V CPLD's are still around--and even offered in PLCC. Take the Atmel 15F series for example. You can do a heckuva lot with the smallest 44-pin member and 32 macrocells (ATF1500A).

    Some spot sources still carry the Xilinx XC9500 devices in 5V versions as well.

    Parallel port programmers for both are very easy to throw together.

    However, the market on "jellybean" 5V logic is sunsetting, particularly as device geometries get smaller. The small 90 nm processes being used today just won't support 5V operation.
  5. cr1901's Avatar
    I sometimes wish PALs were used today to let me do address decoding of multiple peripherals with a single chip... without me having to buy a programmer which costs an arm and a leg. Well, I know address comparator ICs and a microcontroller can accomplish the same thing nowadays, but it seems like SSI 'custom logic' is taboo in this day and age.
  6. gerrydoire's Avatar
    I have a 1.44Meg Capable floppy card inside my IBM PC, so I figured what the hell:

    Purchased one of these gotek things today, works like a charm, if you have a XT IDE, you really don't need one of these things, but hey it's all useless when you really look at, just another tinker toy for the pile.

    It booted IBM Dos 7.

    Scouting the internet, I seen another emulator that could do 1000 floppies, but for the price they wanted, not worth it.

    If you have a 1.44 meg floppy card inside your 8-bit computer and do not have an XT IDE, go for it.
    Updated March 18th, 2013 at 05:08 PM by gerrydoire
  7. Chuck(G)'s Avatar
    The first time I saw these boxes being offered was from a place in, of all places, Vietnam. Embroidery machines are big throughout the East, including Vietnam, India, Singapore and China.

    It's odd that Winchip/Nanjing Qinheng Electronics has the description of the box on their site--and the qhsfd.com maps to a directory on the NQE server. And qhsfd offers a slimline version.

    I suspect that the Indians may have had the box produced in China. Like all good IP, the Chinese believe that imitation is the sincerest form of flattery. But the qhsfd.com site links to embnm.cn, a big embroidery machinery site.

    So who knows? At any rate, qhsfd.com, got started around at least by March, 2009. If you believe the wayback machine, Gotek.in only dates to 2010-2011 or so. It's more likely that the common source is probably neither.

    I've been trying to unravel that one for some time...

    But the Qinheng site says that they've been in the floppy emulation business since 2005 and they're the ones who have had their IP pirated. Note the photo of the old-style emulator on the same page.

    By the way, I did a download of all of the public files from the NQE server (a bash script and curl)--there's a ton of stuff there--datasheets, PCB layouts (Protel format), schematics, programs--all for USB-oriented products. Some interesting stuff there, if you have the patience to wade through a bunch of Mandarin. I wonder if that's how the floppy emulator stuff was ripped off.
    Updated January 18th, 2013 at 10:49 PM by Chuck(G)
  8. RickNel's Avatar
    I'd infer that the orgin was the Indian Go-Tek company, aimed squarely at keeping India's ageing textile industry machinery ticking over. Their website indicates that they expect to make their money by developing custom firmware for clients, so no surprise they put a premium on firmware security. The Chinese cloners must have got access to Go-Tek's servers. They have plenty of form in that area.
  9. Chuck(G)'s Avatar
    I'm not the first to be bamboozled by this one. There are plenty of posts around for ways to get around it, all with no success. ST Micro has posted assurances that the bootloader is unbreakable. Sigh.

    However, I did run across this page and in particular:

    All these chinese devices are copies of some original that nobody knows where it came from.
    Now that's interesting. Last night I started browsing one of the Chinese websites. There's a lot of software available for download, but the descriptions are all in Mandarin, so it's slow going. I suspect that the prototype firmware is available somewhere--after all, all of those copies had to get their software from somewhere. I'll give the effort to find it a few days, just to see if anything turns up.
  10. tingo's Avatar
    Hmm, try looking for backdoors in the serial bootloader?
  11. tingo's Avatar
    Following this with great interest!
  12. Chuck(G)'s Avatar
    I've started to do some probing and reading.

    That unpopulated block of 8 pads by the power connector is now making sense. The pair of pins labeled RST is just what it says--RESET when shorted. At the top end of the block, near the "J3" label we have a +3.3V supply and the BOOT0 pin from the MCU. Tying the 2 of these together causes the serial programmer to be activated after a RESET. The other pins are variously ground, and the USART1 Rx and Tx pins, as well as the SWCLK SWDIO pins for a JTAG debugger.

    So,unless the manufacturer of this thing happened to blow the "protect" fuse, we can get the firmware out (and into) this thing.

    Stay tuned...
  13. Chuck(G)'s Avatar
    I think they're all the same basic board. Some have a USB-to-host connection, for example. The 10 pin header on the rear of the unit can connect to an external "dongle" that changes the image in use and displays the disk number. Note that the serial interface to the display (clock/data lines feeding 74HC164 shift registers connected to the displays allows for any number digits in the display.

    I strongly suspect that the major difference between any of these lies in the firmware.
  14. RickNel's Avatar
    I see there's quite a range of these (minus the Gotek brand) being sold out of Hong Kong on ebay, $25-40. Look like yours, but display digits vary between 0-3.
  15. Chuck(G)'s Avatar
    Rick - yes, currently you can boot a floppy image, so long as it obeys the standard "DOS" 1.44/1.2MB format. As a matter of fact, AnaDisk, ImageDisk and 22Disk think it's a real floppy, so long as you stay within the high-density 512-byte sector format.

    Tingo - My next-after-the-next step is to see if I can D/L the firmware using JTAG and see if I can disassemble it. The first order of business is to buzz out the PCB and get a schematic of sorts for this.

    There should be absolutely no reason preventing us from rigging it for other sector sizes and formats. I did a similar emulator "from scratch" using SD cards and a much slower 8-bit AVR. But if there's a ready-made product that needs only new firmware to do the job, then that's going to beat any DIY project.

    So at least you know my line of thought.

    Gotek offers what amounts to the same version of this for 720K (keeps the synth people happy), so I imagine that it's just a firmware change.
  16. RickNel's Avatar
    I'm following your adventure with this. Curious whether you could boot from a floppy image via this. Also whether it is recognised by older BIOSs or recognised at all without a loaded OS. And whether images in this format can be written to original media via rawrite or dd.
  17. tingo's Avatar
    Wow, that is worse than I expected (the "format" of the usb stick). OTOH, if we could somehow get the device to recognize other formats it would suddenly become more usable. But then we probably would need a way to "mark" the format type on the usb stick too.

    Any chance of getting at the firmware in that mcu?
  18. Robin4's Avatar
    Is this the one for the REV0 cards?
  19. Chuck(G)'s Avatar
    Quote Originally Posted by fjkraan
    Hi, thanks for the reaction!

    I did try to to add tri-state detection, but it is not yet very clear, and the algorithm might not be complete either.
    If you're running out of pins, you may be interested in a port expander that's interfaced with IC. TI has a good selection:

    http://www.ti.com/lit/sg/sszc003c/ss...2cguide_050611

    Registered PALs can be very difficult, if not next to impossible to decode. Because they're not strictly combinatorial (i.e. they have a memory) and can include feedback terms, it can be extremely difficult to figure them out unless you have some prior knowledge of their function. Many old parallel-port dongles used registered PALs as their security device.
  20. fjkraan's Avatar
    Hi, thanks for the reaction!

    I did try to to add tri-state detection, but it is not yet very clear, and the algorithm might not be complete either. It works as you describe: an input connected to the pin to get the actual level and an output connected via a resistor, to push. The reading algorithm should try each potential tri-state pin to push it high and pull it low. It might be possible to add the tri-state to the software, but currently it is just dumping the measured state. I'll add a diagram to the page.

    Currently I use a AT Mega644, which has 30 pins usable. I might switch to an Arduino Mega256 which has around 50 usable pins. I prefer to use them in complete bytes to keep the program simple, so some extra pins become useful when a lot of pins can become tri-state.

    Some of the PALs I try to decode are PAL16R6 (from the TRS-80 MII 68000 card) which have both registered and tri-state capability.
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