Multi-Tech Systems ISI551PC - Manual (Page 6)

1-1
1.1 Introduction
The introduction of high speed, data compression
modems, such as Multi-Tech's MultiModem II TM
Series, has shown that many PC serial ports are
unable to keep up, essentially becoming a bottleneck
for the entire system. The ISI551PC card provides
processing power to reliably transmit data up to
115.2K bps. Using an ISI enables your system's
processor to perform more efficiently. This is because
the ISI handles all of the byte-by-byte interrupts
generated by the asynchronous terminals and stores
the data in buffers. The ISI then generates one
interrupt for an entire block of information and
transfers the block to the system's microprocessor.
This manual provides the hardware installation
procedures for the ISI551PC card. The ISI551PC
card is used with Multi-Tech's high speed modems;
and is a high speed, buffered, single-port serial card,
with its own on board processor. The operation of
the card provides the basis for its name ISI (Intelligent
Serial Interface), 551 indicating the processing power
of a 16550A UART and one port support, and PC
indicating that it is an ISA bus card (8 bit), which is
able to operate in any 286, 386, 486 or Pentium ISA or
EISA compatible bus personal computer. The
ISI551PC card can be accessed by any software
written to the 16550A specification.