I don't think your title matches your post. As for how many devices you can connect to a SATA port, its one device per port.
To answer your post, you can have SATA and IDE devices installed at the same time. For IDE devices you will need to set the hard drive with your OS as the master and the other IDE device as the slave on the jumper settings.
SATA devices don't require master/slave settings and will auto detect.
One of my two answers should solve your problem to the question I think you were trying to ask...
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