Communication38Exception codesThe FSCA-01 RS-485 Adapter Module supports the Modbusexception codes shown below.Exception code Name Description01h ILLEGAL FUNCTION The function code received in thequery is not an allowable action forthe server.02h ILLEGAL DATAADDRESSSThe data address received in thequery is not an allowable addressfor the server.03h ILLEGAL DATA VALUE A value contained in the query datafield is not an allowable value forthe server.04h SLAVE DEVICE FAILURE An unrecoverable error occurredwhile the server was attempting toperform the requested action.06h SLAVE DEVICE BUSY The slave is engaged in processinga long-duration command. Themaster should retransmit themessage later when the server isfree.