UART 1.5 tells if COM ports are configured correctly.

UART lets you check that your COM ports are configured
correctly, with the standard hex port address e.g. COM4:
should be at 2e8, and with the standard IRQ, e.g. COM4
should be IRQ 3.  It also tells you what type of UART chip
you have, usually the old fashioned unbuffered 8250 or the
newer fifo buffered 16450 that is needed for Windows and
OS/2.

It expects this pattern COM1: COM2: COM3: COM4:
                  port:  378   2f8   3e8   2e8
                   irq:    4     3     4     3

usage: UART COM4:
returns:
COM4: is at hex port address: 02E8.
AT style 16450 unbuffered UART.
Port correctly configured to IRQ 3.

UART will tell if the hex port address and IRQ configured
is correct and what it should be.

Copyrighted but may be distributed freely for non-military
use only. Use by UN-sanctioned police actions is expressly
permitted. OPTASM/MASM included. Version 1.5 just embeds the
new phone number and has a bit more documenation.