AXIOMTEK AX10445 Series, Руководство пользователя

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AX10445 Module Series User
’
s Manual
Application
21
C h a p t e r 4
Application
4.1 General
The AX10445 is usually applied in:
Ø
File transfer between two computers.
Ø
Local area network, which include a central computer
(file server) and several remote computers.
There are three ways to access the serial ports in an MS-
DOS system. You can control the serial port through an
installable character device driver, or by installing a TSR
(terminate and stay resident). The third method is to develop
a stand-alone application that includes the interrupt handler
for the serial port.
Before using the serial port, you must set the communication
parameters for each port (these parameters must be the
same for ports transferring data to each other). If you are
using the standard COM1 and COM2 as your serial ports then
the parameters can be defined directly via the function calls
supported in serial high level languages. i.e.:
l
For Turbo C language, issue “bioscom()”.
l
For Microsoft C, issue “_bios_serialcom()”.
l
For Window 3.X, issue “SetComState()”.
Also these two standard ports already have pre-designated
IRQ numbers and interrupt numbers. The pre-designated IRQ
numbers are IRQ3 (interrupt vector number B) for COM1 and
IRQ4 (interrupt vector number C) for COM2.
If these standard parts weren ’ t used, then when you
determine the communication parameter you must write to
the 8-bit registers of the UART (see
Page 13 ) and assign the
IRQ number by selecting jumpers. Once the IRQ numbers are
known, the steps involved in programming are the same as