This read-write enumeration (mapDE(1), setDEzero(2), setDEone(3), ignoreCLP(4)) controls how the ATM CLP bit is translated back to the Frame Relay DE bit, with values 1-3 valid for SIW channels and 1 and 4 valid for NIW channels; on FRSM12 cards, frForward channels must use ignoreCLP and must not use setDEzero/setDEone. An administrator selects mapDE to have DE marking follow the incoming CLP bit, or ignoreCLP to leave the DE bit as received regardless of CLP. For example, on an FRSM12 channel of type frForward, chanCLPtoDEmap must be set to ignoreCLP rather than setDEzero, per the object's card-specific restriction.