Given a sufficiently fast USB stick, I could verify that FlashFloppy 3.39 and 3.44 work well for 2.88MB images connected to an Asus PVI-486SP3. That board has an SiS 496/497 chipset (which is not that relevant) and an UMC8669F Super I/O chip. On the other hand, a Biostar MB-8433UUD with an UMC8663BF does not support 1MBit/s.
I have two Goteks with a SFRKC30AT3 PCB at hand. One is running FlashFloppy 3.39 and has the original AT32F415 processor (32KB internal RAM) on it, while the other one has been upgraded (chip swap) to the AT32F435 (640KB of internal RAM, split between 384KB work RAM and 256KB shadow RAM for the flash), and sports the most current 3.44 firmware. I tested formatting a DOS floppy, running the SYS command, reading in VGACOPY, writing in VGACOPY with and without the "verify" and the "format" option enabled, and every operation worked perfectly. I used a Kingston DataTraveler G4 16GB USB stick for the positive results, and can confidently report that I didn't notice a major difference between the "stock" Gotek and the "upgraded" Gotek.
On the other hand, with a slower USB stick (generic unbranded 1GB stick, which looks like https://www.nordexmedia.com/1gb-black-custom- … wivel-usb-drive), I can report that the bigger RAM (which results in FlashFloppy having more cache available) in the upgrade processor improved things from "any kind of writing is completely unusable" to "in limited circumstances, writing is OK" This list shows the limited usability on the processor with more buffer space. None of the items on that list work with the unupgraded Gotek on using the cheap stick.
- Formatting in DOS works if you hit PAUSE every 20% of the formatting process (to allow buffers to be flushed).
- Running "SYS A:" in DOS 6.22 on a blank floppy pops up multiple "Drive not ready" prompts, which you can answer by "retry" and then the system files get correctly copied (but the second FAT copy was bad afterwards, according to scandisk).
- Writing with VGACOPY works if "format" is on, but one track in the middle of the image and the last 4 tracks required retries by VGACOPY. Maybe this is due to flash-level or FAT-level fragmentation.
- Writing with VGACOPY works not at all if "format" is off
The final result is though that if you experience issues when writing 2.88 floppies, upgrading the processor is just papering over insufficient speed of the USB stick. On the other hand, if your USB stick is sufficiently fast, you even the cheap 32KB works well. So swapping the processor on a Gotek PCB is not worth the hassle in this use case.
Please note that this experience is about using sector-based images (.IMG files) with flash-floppy. I also tried a .HFE file generated using the HxCFloppyEmulator software , and nothing worked with them, not even reading using the fast USB stick in the upgraded Gotek.
