BETA RELEASE OF OS/2 COMMUNICATION DRIVERS
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WITHOUT LIMITATION, WARRANTIES OF FITNESS AND MERCHANTABILITY WITH
RESPECT TO THE INFORMATION IN THIS DOCUMENT AND INCLUDED SOFTWARE
PRODUCTS. . BY FURNISHING THIS MATERIAL, IBM GRANTS NO LICENSES TO ANY
RELATED PATENTS OR COPYRIGHTS.
Copyright IBM Corporation, 1992, all rights reserved.
1.0 INSTALLATION PROCEDURE
a. The following files will be replaced:
These files will be backed up with the extension *.392. If
files with this extension already exist, then NO BACKUP will
take place. The installation utility is assuming that you
are using IBM OS/2 2.0 GA release drivers.
b. Switch to the drive and directory where the BETA files
c. Enter "cominst x:" at the command line where
x: is the drive letter of the OS/2 Partition.
d. To DE-Install the BETA drivers communication driver,
Enter DEINSTL x: where x: is the drive letter of the
2.0 DESCRIPTION OF DRIVERS
The following is a brief description of the BETA
communication drivers for OS/2 2.0. There are new
parameters for the COM.SYS which is located in the
COM.SYS now has new parameters to indicate the COM port
number, the I/O address, the UNIQUE IRQ level and how to
handle spurious interrupts. An example follows:
DEVICE=C:\OS2\COM.SYS (n,xxxx,ii,s) [(n,xxxx,ii,s)]...
where the last parameter is optional.
n : COM port number (usually 3 and 4 but it is
possible to configure any communication port to a
differrent IRQ or I/O Address
xxxx : COM port address
ii : IRQ level
s : Spurious interrupt handling switch
D or d to deinstall COM driver if
more than 1000 consecutive
spurious interrupts occur.
I or i to ignore spurious interrupt.
P or p to post error if more than 1000
consecutive interrupts occur. When
posting an error, some DOS applications
NOTE : Some UART chips or malfunctioning modems can cause
interrupts when no interrupt is expected. These
interrupts are known as spurious interrupts.
COM.SYS also has the following fixes:
1. COM.SYS now uses a different algorithm to test for the
presence of a communications port at the given address.
There were certain cases where a port was not recognized.
2. COM.SYS does not detect Hayes ESP card so that Hayes
ESP card can be used as a regular dual asynch card.
No parameters or settings required. This version of VCOM.SYS
should work better with X00.SYS (and other similar
applications) when COM_DIRECT_ACCESS is ON. COMDD.SYS (which
is required by older DOS applications such as BASIC) should
also perform better. COMMDD.SYS is loaded into the DOS_DEVICE
setting for a Virtual Dos Machine.
2.2.1 COM_DIRECT_ACCESS DOS property
When COM_DIRECT_ACCESS is ON, VCOM.SYS will allow a DOS
application to access the communication ports directly. This
DOS property makes LapLink III, FaskLynx, FSDUAT, AS/400
Asynch Router, MS WORD work in VDM session. However, since
the buffers in COM.SYS cannot be used, characters may be lost
and and some applications may suffer from the lack of
buffering. With most DOS applications, COM_DIRECT_ACCESS
should be set to OFF as its default setting.
2.2.2 COM_SELECT DOS Property
COM_SELECT allows the DOS session to select only one
communication port to be used by the session. The
communication ports which are not selected will be hidden from
the DOS session. There are some DOS applications which take
over every available communication port. This DOS property is
effective in preventing those DOS applications from taking
over all the communication ports. An example of a DOS
application which attempts to control all the communcication
ports is LapLink Pro. If LapLink Pro and another application
which accesses a communication port are executed at the same
time, it is necessary to set COM_SELECT. The default setting
COMM.DRV contains the support for COM3 and COM4 in WinOS2.
This COMM.DRV requires the new VCOM.SYS.