Based on the naming, I had assumed that FIDO1100, FIDO2100, FIDO5100 and FIDO5200 are fundamentally the same. But I notices that the FIDO1100 in the datasheet is advertised as a "regular" MCU which can be C programmed over JTAG. While the other 3 chips seems to be actual special purpose microcontrollers which acts as a ethernet switch.
What I try to understand, what are the differences between the 5x00 family and the 2100? Newer, more protocols more efficient? And is it correct that the FIDO1100 does not act as an ethernet switch, rather was designed as a 'perfect' host controller for the FIDO2100?
For completeness sake here is a link that describes the RapID use case which encompasses both the fido1100 and the fio5100/5200.
The fido2100 was an older ethernet switch chip developed to support the Device Level Ring feature that is specific to EtherNet/IP. So it is just that an EtherNet/IP switch chip that supports DLR. The fido5100/5200 was developed to take advantage of DLR and other more complex layer 2 features for other Industrial Ethernet protocols.
Thank you very much.