RS-232/RS-485/RS-422 fiber modem,provides port-to-port transparent transmission among RS-232, RS-485 and RS-422 serial ports/ OverviewFM280 is a RS-232/RS-485/RS-422 serial fiber modem, designed according to industrial standard. The hanging designs support DIN-rail installation. Now many users choose RS-232/RS-485/RS-422 serial fiber modem to cope with electromagnetic interference and extend RS- ...