Been trying to find a clear answer on this. I keep seeing notes that USB based concentrators are no longer supported. It seems this is related to the USB to SPI FTDI chips. Does this hold true for the concentrators that have a MCU that are USB connected to the host but SPI connected to the chipset? As an example, the N-Fuse mini-PCIe concentrator has the onboard STM32 MCU. Looks like this is based on the PicoGW reference design but can’t determine if that ref design is now outdated.
The PicoGW design is ‘recent’ and is supported. (It uses a different code base.)
The phased out design based on the USB to SPI chips was retired some time ago, it did not scale due to the communication overhead. Some packet forwarders (poly & mp) still provide support for gateways based on this design to allow owners of older hardware to run up-to-date software.
Best to avoid hardware based on this design when purchasing new as it is unclear if newer software can still be modified to support USB connections.