SASI — Shugart Associates System Interface. Он стал стандартом SCSI, который используется до сих пор.

In 1982 I had the opportunity to design a hard disk interface for use with SWTPC 6800 and 6809 Computer Systems. The drives were to be the new 5 1/4 inch Seagate Technology ST506 style (MFM) and the computer interface was to use the SASI.

Схема интерфейса
оригинал

SASI Hard Drive

ASCII HD Interface