Hasty Briefsbeta

The world has a running Rational R1000/400 computer again (2019)

4 days ago
  • #SCSI
  • #VintageComputing
  • #R1000
  • SCSI command 0x0d identified as returning the length of burst errors corrected with ECC.
  • Custom SCSI2SD firmware hacked to return specific MODE SENSE values, enabling R1000 to boot successfully.
  • R1000 uses 'modern SCSI' with linear block-numbers for booting but operates with Cylinders, Heads, and Sectors in the real system.
  • Successful restoration of R1000/400 computer functionality, including memory board reconfiguration and diagnostics.
  • PSU repair and capacitor replacement documented, highlighting challenges with soldering and insulation deterioration.
  • Discovery of EEPROM address bit swapping issue affecting reverse-engineering efforts.