>Who knows how to retrieve the serial port base i/o address programmatically ?

I havent tried to da anything like this since back in the day... But when I looked I felt that the reg has to hold this info, well I don't believe it does. So I looked at the device mgr to see if it knows what the port addy is and it did indeed seem to (and display it). So I thought that if you querry the driver you would get the info. In my case the driver is serial.vxd after looking more I found two functions that appear to be driver independant: Because it appears that you want to do it old school style :) so according to what I read ( I only spent about an hour on this ) You need to get the comm state in order to fill the _DCB structure and then you can convert the DCBN structure to a ring 0 DCB. This should make the port itself accessable directly via code. I did not have the time to really experiment with this but I hope you can get your full answer from some of this.

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_DCB - device control block (structure)

_VCOMM_GetCommState - Gets the current communications settings for a communications resource. Uses the C calling convention

_VCOMM_Map_Win32DCB_To_Ring0 - convert a Win32-style DCB to a Ring 0 DCB.
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