There's renewed interest on the development of drivers for Realtek PCIe card readers and it's fantastics news!
Last year, we reported here on Cholonam's work that, building on the original work of developper Sinetek, gave a new life to some of our Realtek card readers. It was pretty good stuff and allowed many of us with, say RTS525a card readers, to finally be able to use SD cards under macOS. Performance was however pretty limited.
This year, Austere.J (aka Firewolf) has embarked on writing a brand new driver and, my God, is it good! The driver is under active development as we write but Austere.J has started on the RTS525a with super results and he's adding support for other Realtek RTS models too.
2 x major improvements compared to Cholonam's driver:
the card reader is now reported as built-in in SysInfo the card's full performance is being achieved
You can follow the on-going R&D here at Insanelymac and drivers are posted here on FireWolf's GitHub repo.
Please join me in helping Austere.J in the testing and give him the support and thanks he deserves.