The Disto Hard drive adapter is SASI. (I don't know about the 4-in-1.) It runs a SCSI to MFM board on my CoCo Hard Drive system. If I understand correctly, the protocols are backwards compatible. Which is one reason I've not given up on "my" Tandy hard drive "controller" yet. Bruce W. > And I'm told it wasn't even scsi, but sasi,