The following A firmware is compatible with the SA variants of the following:

PX-708
PX-712
PX-716
PX-755
PX-760

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The following external drives of E, U, and UF can use the same firmware as
their internal variants of TS/S and T/TA/A/SA:
[This list will be updated with further research.]

PX-40TS (SCSI unit)
PX-708 (A and A2; note the separate FW for each)
PX-712
PX-716 (both A and AL; note the separate FW for each)
PX-755
PX-760
Premium
Premium2
PX-R412C (SCSI unit with Caddy)
PX-R820T (SCSI unit)
PX-W series (please note your model suffix when flashing your external unit)


Firmware Notes:

* A and SA drives generally use the same firmware, with some exceptions.
  [Exceptions being TS/S variants (which are SCSI units; quite different from
  their ATA variants), later SA (SATA) variants, the PX-S88TU (which is its own
  unit entirely), and the PX-S2410TU. Note the separate FW for later Plextor
  models.]
* Later external U and all UE drives use different firmware from their
  internal variants.

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Suffix Meaning:

C - Caddy units
T - Tray units
L - Slot-loading units

C - SCSI Caddy (only PX-R412C used this from noticing)
CS - SCSI Caddy (very early to early Plextor SCSI caddy units)
TS - SCSI Tray (early to mid Plextor SCSI tray units)
S - SCSI (mid-late to late Plextor SCSI tray units during SCSI to ATA transition)
T - Tray (early Plextor ATA tray units [except PX-R820T, as it's SCSI tray]
    during SCSI to ATA transition)
TA - Tray ATA (early Plextor ATA tray units during SCSI to ATA transition)
A - ATA (mid to late Plextor ATA units; pretty much all tray ones then)
AL - ATA [Slot-]Loading (only one known unit - PX-716AL)
SA - SATA (all are tray units at this point, IIRC)

i - internal (SCSI variants and early ATA variants)
e - external (SCSI variants and early ATA variants)
U - USB (external variants only; usually ATA)
F - FireWire (external ATA variants only; used with U)
E - External (external SATA variants only; used with U)

Suffix Note:

* S and TS were used interchangeably during the SCSI to ATA transition. Units
  would sometimes show S on the front (and sometimes in Device Manager), but
  will show TS on the label. This is not as confusing at this point since caddy
  units were no longer made in the transition's later stages. This also applies
  to early ATA units and T and TA suffixes, though only regarding the label on
  the top of their units.

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Created: 2022/06/08
Last Updated: 2022/06/12