Re: ProDOS / Autostart ROM ID bytes

["vladitx" <vladitx@nucleusys.com>]

David Empson wrote:
> mdj <mdj.mdj@gmail.com> wrote:
>
> > David Wilson wrote:
> >
> > > Well spotted. Unfortunately this is the original Workbench ProDOS
> > > manual and you cannot believe all you read in it.
> > >
> > > e.g. Page 113 - In reality, only slot 5 supports 3-4 drives and they
> > > end up in slot 2.
> >
> > At least in versions of ProDOS prior to 2.0.1 anyway.
>
> Also of note: the ProDOS block driver mechanism for slot 5 drive 3 or 4
> (remapping to slot 2 if it isn't occupied by a disk controller) was
> added in ProDOS-8 1.2. It only works if the card is slot 5 is able to
> cope with the "wrong" slot appearing in its unit number.
>
> > The last release remaps devices beyond 2 on any slot to the remaining
> > free slot/drive positions.
>
> ... but it only does this for devices which support the SmartPort
> firmware interface, and doesn't make use of any spare drive 2 unit
> numbers where drive 1 is mapped to a real device. For example, a
> "slinky" RAM card in slot 4 would use S4,D1, but nothing will be
> allocated to S4,D2.

Because I have very limited experience with ProDOS in the past, what
should I do if I want to have more than 2 volumes/drives per slot? Is
it possible without SmartPort?

Suppose I have this ProDOS driver at $C600 (Slot 6), which reports at
$C6FE that it has 3 volumes (bits 5:4 == 11b). Will it work not being
in Slot 5? If yes, shall I do something else, except checking unit
number at $43, which will have different slot/drive mapping? And then,
is '3' really meaning 3 volumes or 4?

Finally, Paul's document at
http://linux.cis.monroeccc.edu/~paulrsm/6502/PDOS8TRM.HTM says:

-----------------------------
$43
Unit Number:

    7  6  5  4  3  2  1  0
  +--+--+--+--+--+--+--+--+
  |DR| SLOT|   NOT USED   |
  +--+--+--+--+--+--+--+--+

*Note:* The UNIT_NUMBER that appears in the device list (DEVLST)
in the system globals will include the high nibble of the status byte
($CnFE) as an ID in its low nibble.
-----------------------------

Is "SLOT" field really two bits only, or this is just a typo?

  -- Vladimir