Technical information

Using NewBIOS Serial Solutions
Chapter 4
Using NewBIOS.
Introduction.____________
NewBIOS is an INT14 upgrade that is installed
automatically by the device driver NewCOM.SYS, NewBIOS
provides extra function calls designed to make serial i/o easier.
Since a few users may wish to NewBIOS as a stand alone
program and the NewBIOS.com program is provided on the
Serial Solution disks. The NewBIOS.com program ONLY needs
loading if you have chosen not to load NEWCOM.SYS in the
CONFIG.SYS at boot time.
The ROM BIOS._______________
PC compatible computers share a wealth of software
supplied in the machine’s ROM, the ROM BIOS (Basic Input-
Output System). This provides services to assist the operating
system and applications programs in using the hardware of the
machine.
One group of services is provided to manage the
computer’s serial communication ports (RS232 ports). These are
called the asynchronous communications services, and will set
parameters such as baud rate, send characters, receive characters
and report the status of the ports. The asynchronous services are
however limited to only four ports, leaving a machine with more
ports ’out in the cold’. Hence the need for NewBIOS. The code
of NewBIOS replicates the functions of the ROM BIOS but
allows up to 32 ports to be used, and adds functions to support
the extra cards and the device driver NewCOM which uses
them.
NewBIOS is installed either by the device driver NewCOM
or by running the program NewBIOS.com. Both ’patch’ interrupt
14H, through which the ROM asynchronous services are
accessed, so that any program which attempts to use the ROM
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