Single Channel RS-422/RS-485 Multi-Protocol PCMCIA Card RS-422 or RS-485 serial interface Provides Bisync, HDLC and SDLC synchronous communication protocols 4 Mbps maximum data rate Configured as DTE 2K transmit and receive FIFOs Programmable baud rate generator DOS, Windows and OS/2 supported SYNCDRIVE software included PCMCIA Card Services Specification 2.1 compliant
The MPAP-200/300 is a Type-II PCMCIA card which adds a single multi-protocol serial interface using a Zilog 85230 compatible SCC controller. The port can be configured as RS-422 by connecting an 100 Ohm resistor, or as RS-485 by connecting a 60 Ohm resistor. The SCC can support asynchronous formats, byte-oriented synchronous protocols such as IBM Bisync, and bit-oriented synchronous protocols such as HDLC and SDLC. The SCC also offers internal functions such as on-chip baud rate generators, and digital phase-lock loop (DPLL) for recovering data clocking from received data streams.
Because the PCMCIA 2.1 standard does not support direct memory access (DMA), the MPAP-200/300 supports only interrupt-driven communications. To compensate for the lack of DMA, the card is equipped with 1024-byte transmit and receive FIFOs. With the FIFOs enabled, data can be moved to and from the SCC in large blocks, providing for high data throughput and low interrupt overhead.
The MPAP-200/300 provides standard data rates of 0.6, 1.2, 2.4, 4.8, 9.6, 19.2, 38.4, and 57.6 kbps. Higher data rates up to 2.45 Mbps are achievable subject to the limitations of the cabling and the interrupt response time of the host computer. The MPAP 200/300's top speed is limited by the 85230 SCC, and with an upgraded crystal the card can reach speeds to 4 Mbps.
All necessary software is included to install and configure the card for use with DOS/Windows 3.x, Windows 95/98, and OS/2. In addition, the frame-level HDLC and Bisync driver, SYNCDRIVE, is included free.