The M1k2 supports two IO boards which can each sport up to eight MADI I/O. At the time of this writing, there are boards with BNC, SC and SFP modules available. To get a current overview of the different IO board configurations, please see the DirectOut web page.
To see the details of your current setup, please go to Misc → Version.
The IO boards can be added, swapped or removed during operation.