DATA UPSTREAM/DOWNSTREAM TRANSMISSION APPARATUS IN ADSL LINE STATE USING PARITY

摘要

PURPOSE: A data upstream/downstream transmission apparatus in ADSL(Asymmetric Digital Subscriber Line) line state using a parity is provided to transmit data attached 1 bit parity by a unit of 4 bits to a serial interface of ADSL. CONSTITUTION: A first OR device(21) receives transmission data and then performs an ORing operation. An inverter(22) receives a transmission enable signal(TX_EN1) and performs a phase inverting. Second to sixth OR devices(23-27) receive transmission data of the first OR device(21) and the output of the inverter(22) and perform an ORing operation. A serial/parallel conversion unit(28) receives the output of the second to sixth OR devices(23-27) and then outputs a serial transmission data(TXDA). A buffer(29) buffers 5 divided signal(Q1) of a serial clock signal(TXCKA) and then makes a parallel clock(TXCLK1). First to fourth flip-flops(30-33) receive the serial clock(TXKA) to their input terminals and then divide. An NOR device(34) receives the signal of the first to fourth flip-flops(30-33) and performs an NORing operation.