Advantech PCL-849, Руководство пользователя

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4 PCL-849 User's Manual
Description
The PCL-849 series are four port serial communication interface
cards. Each port can be configured individually to RS-232 using on-
board jumpers.
PCL-849A/849B serial ports are implemented using 16C554 UARTs
which make serial I/O more reliable. For higher performance, 16654
UARTs can be installed in place of the 16C554 to create the PCL-
849+. By buffering data into 64-byte packets before putting it on the
bus, UARTs drastically reduce the CPU load. This makes the
PCL-849+ especially suitable for high-speed serial I/O applications
under multitasking environments and for applications involving high
data rates.
PCL-849 series cards support two operating modes: standard mode
and enhanced mode. In standard mode each of the four port addresses
can be set individually. In enhanced mode, all four port addresses can
be set automatically. The PCL-849+ also supports either shared IRQ
or independent IRQ functions. When an on-board interrupt occurs the
interrupt status register (vector address) indicates which port generat-
ed it. The shared interrupt can be set to most common (extended) AT
interrupts. This simplifies programming, speeds interrupt processing
and frees interrupts for other devices.
Each card comes with DOS drivers and PC-ComLIB, a serial commu-
nications library. PC-ComLIB supports most common languages,
including C, Pascal, Visual Basic, assembly and Clipper. The PC-
ComLIB package also includes the DataScope viewer, terminal
emulator and self-diagnostics utilities for easy troubleshooting and
debugging.