Quatech's single port RS-232 or RS-422/485 synchronous serial PCMCIA cards support asynchronous data formats as well as byte-oriented synchronous protocols such as BiSync, and bit-oriented synchronous protocols such as HDLC and SDLC. The card's robust design provides 1024-byte transmit and receive FIFOs, and a SCC with advanced internal functions including on-chip baud rate generators and digital phase-lock loop (DPLL) for recovering data clocking from received data streams.