The Coleco Adam home computer also had tape drives which were random-access seekable block devices. 2 tracks with 128 1k blocks per track for a total capacity o

The Coleco Adam home computer also had tape drives which were random-access seekable block devices. 2 tracks with 128 1k blocks per track for a total capacity of 256k. Coleco called their tapes digital data packs. They were standard compact cassette tapes with some additional holes. If you drilled the appropriate holes you could use standard tapes instead of paying the Coleco premium. CP/M required booting from a block device and as far as I know the Coleco Adam was the only computer which could boot CP/M from a tape. Once booted to CP/M the tape drives were treated just as floppies.