Replying to ATA master, SATA Slave Drive Question

As of recent, my moms computer has been messing up, the master hard drive that is. This main hard drive with all the files on it is SATA format. We do have a slave drive that we currently booted from, which is ATA format. We are attempting to get the files from the SATA hard drive so we can put them back on to the computer. Do you guys know if you can have an SATA drive as a slave to an ATA? And if so, HOW!

Any help would be greatly appreciated