USB is in the AMR/iFi DNA - part #5
Over a decade of development
2013. The Great USB 3.0 Crisis.
It was not all smooth sailing. In 2013 we started to receive reports that the iDSD nano was not working correctly with the latest Mac laptops. After much hair pulling, cussing and copious amounts of black coffee, working closely with XMOS, we were able to pin down the problem.
It turned out that that the latest Intel chipset's USB3.0 hardware was
actually not 100% backwards compatible with the USB2.0 standard. How these chips ever passed validation and formal USB testing - well, one has to email Intel. Now in theory, Intel and Apple should have gone and fixed this mess. But they just shrugged and replied "You want us to recall millions of laptops and computers – don’t think so."
The bottom line was that there were millions of machines out there and more coming by the day, with USB systems that had USB2.0 broken on the (often only) USB3.0 ports and not only our products, but every product using XMOS Audio ended up not working. Ohhh my.
https://superuser.com/questions/482...wards-compatibility-problems-with-2-0-devices
There was a workaround in disabling the USB3.0 hardware in the BIOS for Windows and a by far more involved sequence of actions on Apple Macs. In practice, it proved difficult to convince our customers that the fault lay with Intel and that they needed to disable USB3.0 (even if they were not using any USB3.0 devices).
Thus, it was clear we had to fix the XMOS firmware, in such a way that would not only work well with the new Macs & PCs but remain fully USB standard compliant. It took many nights burning the midnight oil by both software teams (XMOS and our own) before suitable firmware updates could be made available.
If we learned anything from this episode (other than more about the inner workings of the XMOS USB Audio solution than we ever wanted to know, though it came in handy later), USB3.0 was here to stay and to ignore it would be pure folly.
We learned a great deal from this incident. The lesson was that Apple and other PC makers were moving to USB3.0. As the old adage goes, “the trend is your friend.”
To us, back then, we saw USB2.0 in the same light as the Nokia3310 (original) well, kinda old.
https://www.thesun.co.uk/news/2823091/oldest-mobile-phone-uk/