Using serial devices under SCO Xenix above COM 2

[barton]

Recently the excerpt below was posted by Ross Oliver at SCO.

>However, if you can set these boards to use other interrupts, then you
>can use them alongside existing COM1 and COM2 devices.  To do this, you
>will have to modify the /usr/sys/conf/master file to tell the serial
>driver to handle the additional interrupts.  Modify the "vec3" and "vec4"
>columns for the "sio" entry, then rebuild your kernel.

>Ross Oliver
>Technical Support
>The Santa Cruz Operation, Inc.


My question is:
How do the entries in the vec3 and vec4 
columns relate to the COM ports and what values should
be placed where? Since vec1 and vec2 are 3 and 4 respectively,
am I correct in assuming that vec1 is for COM2 which is
normally IRQ 3 and that vec2 is for COM1 which is normally
IRQ 4 ??

If this is true, then are the vec3 and 4 columns also reversed
i.e. COM4 and COM3 respectively?

I recently tried this with an internal modem that supports
COM1 thru COM4 and IRQ2 thru IRQ5 to no avail.

Does anyone have any suggestions or better, definate answers?
-- 
Barton A. Fisk          | UUCP: {attctc,texbell,vector}!warble!holston!barton
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