INTRODUCTION
The Am85C30 and Am8530H SCCs (Serial Communications Controller) are dual channel, multiprotocol data communications peripherals designed for use with 8- and 16-bit microprocessors. The SCC functions as a serial-to-parallel, parallel-to-serial converter/controller. The SCC can be software configured to satisfy a wide variety of serial communications applications, including: Bus Architectures (full- and half-duplex), Token Passing Ring (SDLC Loop mode), and Star configurations (similar to SLAN).
The SCC contains a variety of internal functions including on-chip baud rate generators, digital phase-lock loops, and crystal oscillators, which dramatically reduce the need for external logic. In addition, SDLC/HDLC enhancements have been added to the Am85C30 that allow it to be used more effectively in high speed applications.

The SCC handles asynchronous formats, synchronous character-oriented protocols such as IBM BISYNC, and Synchronous bit-oriented protocols such HDLC and IBM SDLC. This versatile device supports virtually any serial data transfer application (telecommunications, cassette, diskette, tape drivers, etc.).
The device can generate and check CRC codes in any Synchronous mode. The SCC also has facilities for Modem controls in both channels. In applications where these controls are not needed, the Modem controls can be used for general purpose I/O.