Kontron PCI-COM-8ULP, Руководство пользователя

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PCI-COM-8ULP User’s Guide page 27
Chapter 3: Programming
Sample Programs
There are sample programs provided with the card in C, Pascal, QuickBASIC, and
several Windows languages. DOS samples are located in the DOS directory and
Windows samples are located in the WIN32 directory.
Windows Programming
The card installs into Windows as COM ports. Thus the Windows standard API
functions can be used. In particular:
Š CreateFile() and CloseHandle() for opening and closing a port.
Š SetupComm(), SetCommTimeouts(), GetCommState(), and SetCommState() to
set and change a port’s settings.
Š ReadFile() and WriteFile() for accessing a port.
See the documentation for your chosen language for details.
Under DOS, the process is identical to programming any 16550- or 16750-compatible
UART.
Address Map
The core of the UART function is supplied by the EXAR XR16L788 chip.
This chip is 16550 and 16750 compatible, but has extra features that require
communicating with an additional 8 registers per channel. For instance, it is necessary
to set the “Auto RTS” function. (EXAR refers to this function as “Auto RS485" in their
literature). The required writing to the UART is done automatically when the card is
rebooted.
In order to utilize standard software that communicates only with the first 8 registers of
each channel, addresses are remapped on the card.
The 8 UARTS occupy the first 64 addresses.
The interrupt status register is located at base + 40h.