• Comparing POS[n] values for IOMEGA PC4n interface adapters

    From Louis Ohland@21:1/5 to All on Mon Jun 13 07:21:41 2022
    Pretty much the same, the PC4 has a PREEMPT item that is moved into
    "Fixed Resources" on later adapters [PC4B, PC4F], the PC4B/HD has a "Termination" item.

    The POS[n] values are the same [except termination, I looked at all bit values]. My SWAG, the PC4n adapters use a 53C9x variant. It is possumble
    the 53C90 was kept in service for most variants, dunno. The later 53C92
    is software compatible with the 53C90, just that the enhancements are
    only accessed with the proper calls, other than that, the enhancements
    are quiet as a tomb.

    What we know of, or suspect, so far:

    PC4 Non-booting, 53C90, GAL/PALs for interface
    PC4A ? Non-booting, 53C9x, 86C01, lacks BIOS/support components, DB37
    PC4B, bootable, 53C9x, 86C01, BIOS, DB37
    PC4B/HD, bootable, 53C9x, 86C01, BIOS, HPDB-50?
    PC4B/F, bootable, 53C9x, 86C01, BIOS, DB37 Adds Floptical, M-O support

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)