ABSTRACT
From the beginning, the Pro¦safe solution was subject to certain design constraints: compatibility with existing Pro¦bus/Pro¦net physical layers, interoperability with existing devices, and compatibility with existingmodulardevices.Anysolutionmustattempttoguaranteetheerror-freedeliveryofdata, orthedetectionofdatawitherrors,betweencommunicatingdevices,suchasaPLC(F-Host)andanI/O
device (F-Device). Implementation of the error-detection mechanism as separate ¦rmware layers in the communicating devices allowed these constraints to be met.
