Some context about the what happened years ago with fake (but compatible and working) FT232 chips that were intentionally bricked by FTDI updated Windows driver, that is, hitting (often unaware) users instead of counterfeiters.
And amusingly, the bricking worked because again the clones worked better. The clones had implemented FTDI's EEPROM interface as designed, 16 bits at a time, while FTDI apparently had used a 32bit array for the internal FT232 EEPROM, and so would buffer 16 bits and only write all 32 bits when you issue writes to odd addresses. FTDI's bricking code uses writes to even addresses only (including computing a preimage attack on their checksum algorithm, as the checksum is at an odd address so they can't change it), which is why it doesn't affect the real ones.
In this particular case, the commonly-available FT232 clones supposedly worked better than the original - the bit banging mode actually worked reliably on the knock-offs, whereas not so much on the actual FTDI chips. (The difference that FTDI used to brick the clones was that writing to the EEPROM one byte at a time, which wasn't allowed according to the datasheet, worked on the clones but not their own chips.)
Unfortunately, the clones also weren't clock stable at all - they were fine at 115200 and such, but if you pushed them up to 3Mbaud or so, they mostly read/wrote garbage. I put a few of them on a good scope and the timing was just all over the place. The legit FTDIs are rock solid on their timing even up at high baud rates.
So I got some legit chips and just did the surface mount rework to replace the fakes with the legit ones and solved my problem. I had no idea when I got the adapters that they had fake chips on them. :/
Bit bang mode is the opposite. The clones work fine. The legit ones don't work at all (completely random timing) except at 3Mbaud (the official workaround), but at that speed you can't keep the buffer fed via USB so it's useless.
This is incredibly interesting. From the articles I've been able to dig up, it sounds as though they've outright admitted to breaking the counterfeit products and it was not an accident[0].
Rather than simply state "We've detected a counterfeit product. If our driver works at all with this product, it will probably be unreliable. It may also break it, entirely. We recommend buying a replacement from (xyz) and requesting a refund from the retailer your purchased it from" Maybe allow them to continue "at their peril", but intentionally break it? That's just stupid.
Consider that this is a device that is probably being used by a company, a developer or otherwise power-user who will likely purchase more than one, did intentionally breaking the one they had make them want to purchase a genuine one or any future product from you? Or did you just cause a poor sysadmin to make it their mission in life to cause your future bankruptcy? It'd make me investigate any alternative to an FTDI product for any future purchase, and they did that, not the counterfeit-maker.
This is such an awesome "punch the customer" response; it's like the RIAA/MPAA are moonlighting in management over there. I loved the FTDI official response, somewhere highlighted is how awful counterfeits are for their business. It's really difficult to feel sympathy for a company who so recklessly disregarded my business by destroying something I owned that they didn't make -- trademark/counterfeit law aside, the only person who got victimized twice was the person who thought they purchased an FTDI product.
Yeah, I used FTDI back when they first came out and there was nothing else like it on the market (that I know of, anyway). Would never use them again after that little stunt.
https://www.microchip.com/forums/m828027.aspx
Luckily Open Source drivers were unaffected. One more point in favor of Open Source, and a good argument to stay away from products by FTDI.