PROTOCOL CONVERSION DEVICE

PURPOSE:To reduce the conversion time of an information block or frame procedure by using a character converter converting a data from an 8-bit code into a 7-bit code and from a 7-bit code into an 8-bit code in the unit of characters respectively at the reception of data. CONSTITUTION:When blocks STX-ETX are received from a basic procedure terminal equipment, a basic procedure control section 5 applies a basic check, a 7-bit of a character code part from a 10-bit code except start/stop/parity bits is extracted to discriminate the block STX. An HDLC procedure control section 6 constitutes a header of the information frame and sends it to a high level procedure terminal equipment. An AND gate 1 gives a data next to the block STX to a character conversion section (B H) 3 through a character buffer 2. Then the code is converted from the 7-bit code of the basic procedure into the 8-bit code of high level procedure together with the shift control and the result is sent to the high level procedure terminal equipment through an OR gate 7.