PURPOSE: To perform accurate information processing, by providing one-bit control information in a transfer data, in a transfer system of lamp information for terminal devices of a telephone exchange system.

CONSTITUTION: When a head block of lamp information is supplied from a terminal DI of a start-stop synchronous reception circuit 1, illumination or distinguishing information is transmitted from terminals R0∼R6, discriminating information is from a terminal R7 to a transfer number counting circuit 2, and a signal from a terminal DR is transmitted to a set pulse forming circuit 5. One- bit lamp information detecting signal from the terminal DR is controlled for the rise with a clock pulse at a shift register 51 of the circuit 5, outputted from an NOT gate 54, and a one-bit signal delayed for a prescribed time from the rise is applied to a gate GT of a decoder 31. Thus, serial lamp reception information is converted into parallel signals and displayed on lamps, then the discrimination of head data can be executed easily and the order of transfer data can simply be discriminated.