B&B Electronics ESCLP-100 - Manual - Manual (Page 13)

2.4 QVCOM.SYS Parameters (Address/IRQ Masquerading)
The QVCOM.SYS device driver virtualizes the base address and interrupt level (IRQ) for
serial ports accessed in a DOS or Windows session. In cases where DOS or Windows software
cannot properly handle the actual hardware settings, the virtual driver can pretend that the serial
port is installed using other values. This is called "Address/IRQ Masquerading."
This feature can be especially useful in trying to use legacy DOS or Windows software
with PCI serial ports. To use it, simply add the proper parameters to the QVCOM.SYS line in
the CONFIG.SYS file and reboot the computer. There is no option for screen output of the
virtual device driver's configuration, so great care should be taken in exercising this option.
2.4.1 Important considerations when using masquerading
{ When a serial port is masquerading, it is still available to OS/2 applications using the
"COMx" port name.
{ DOS and Windows applications using the port must not attempt to use the actual hardware
settings to access the port.
{ The address and IRQ to be used for the make-believe values can not be used by other
hardware.
{ It is not possible to change the port number ("COMx" port name).
Parameter format: (port,io,irq)
port Port number, 1 or 2 decimal digits
The actual port number. For example, for COM3, use "3" or "03".
io Base I/O address, 3 or 4 hex digits
The base I/O address where the serial port will pretend to reside. For example, to masquerade at 3e8
hex, use "3e8" or "03e8". This address range should not be used by any other hardware in the system.
irq Interrupt (IRQ) level, 1 or 2 decimal digits
The hardware interrupt level (2-15) the serial port will pretend to use. This IRQ should not be used by
any other hardware in the system.
Example: (5,3F8,4)
Force COM5, regardless of its actual hardware settings, to appear as a standard COM1 at
base address 3F8 hex and IRQ4 to all DOS and Windows programs. OS/2 programs can still
access the port as "COM5."
Quatech Asynchronous Serial Device Driver for OS/2 10