The HiMD Walkmen are SCSI disk drives. They only use the LUN zero.

These standard SCSI commands are used:

• 00: Test Unit Ready
• 03: Request Sense
• 12: Inquiry (only page 0, standard inquiry) Vendor specific inquiry part: 36-43 = "UMD ID"; 44/45 = System Info; 46/47 = Command info [16 bit words little endian]
• 15: Mode Select (6) (see below for pages)
• 1A: Mode Sense (6) (see below for pages)
• 1B: Start/Stop Unit
• 1E: Allow/Prevent medium removal; "Start motor" not suppoted
• 23: Read format capacities (see SFF-8070i, link below)
• 35: Synchronize Cache, "Immed" bit at Byte 1, Bit value 0x02
• 55: Mode Select (10) (see below for pages)
• 5A: Mode Sense (10) (see below for pages)
• A3: Send Key - SCSIDRMInfo
• A4: Report Key

They support the following extensions to standard SCSI disk drive support:

• C0: Read HiMD
• C1: Write HiMD
• C2: SCSIHiMDControl
  • C2/00: Erase HiMD
  • C2/01: Format HiMD
  • C2/0E: Begin ICV Transaction
  • C2/0F: Recommend Synchronize Cache
  • C2/10: Switch Interface
  • C2/11: Get Leaf ID
  • C2/20: Load Audio TOC
  • C2/21: Pause Audio
  • C2/22: Play Audio
  • C2/23: Scan Audio
  • C2/24: Search Audio
  • C2/25: Seek Audio
  • C2/26: Stop Audio
  • C2/40: Read Defect List
  • C2/41: Read Zone List
  • C2/50: Get Time
  • C2/60: Read Audio Status
  • C2/90: Set Time
  • C2/A0: Extended Play Audio

The following mode pages are supported

• 01: Read/Write Error recovery parameters
• 08: Caching
• 1B: Removable Block Access
• 1C: Timer and Protect
• 21: HiMD Playing

See SFF-8070i for more information about all mode pages except for the HiMD playing page.

See HiMDDownload for a trace of downloading a short LPCM track to an HiMD device using Sonic Stage