Re: IIc + SmartPort behavior

[Michael J. Mahon <mjmahon@aol.com>]

Peltier Cedric <pcedric3@free.fr> wrote:
> Le 07/11/2011 13:54, Steven Hirsch a écrit :
>> On 11/06/2011 11:36 PM, Michael J. Mahon wrote:
>>> Steven Hirsch<snhirsch@gmail.com> wrote:
>> 
>>>> At this point, the primary issue with IIc+ is that it won't boot the
>>>> spvhd. Both the IIgs and IIc+ try to access the spvhd a bit before its
>>>> firmware comes ready, so you generally need an immediate Oa-Ctrl-Reset
>>>> after powerup. Then, you can do PR#5 and boot from the internal 3.5
>>>> diskette. When P8 comes up, as many as three virtual disks will be
>>>> recognized (assuming you aren't using an ancient ProDOS 8).
>>>> 
>>>> I don't consider this any sort of show-stopper and I'm sure Cedric will
>>>> sort out the firmware.
>>>> 
>>>> Steve
>>> 
>>> I'm a bit surprised that it doesn't keep mapping logical devices until it
>>> runs out of mappable slots.
>> 
>> Apple's specs claim support for a total of (4) devices on the Smart bus.
>> That limit appears to be real.
>> 
> 
> Initialy the SPVHD was limited to 4 virtuals drives, but I pushed this
> limit up to 10 virtuals drives after a discussion with Geoff Weiss.
> Prodos 8 2.0.3 seem to be able to map more than 4 devices using all
> available slots. Nevertheless, some 8 bits applications don't handle
> nicely so much devices.
> The devices limitation should be correlated with electrical limitation at
> the time, and I suppose the maximum number of devices that Prodos 8 can
> handle evolved to follow hardware evolutions.
> 
> Cedric

Exactly as I expected. 

Certainly Smartport addressing would not be limited to four devices. 

Most applications use ProDOS prefixes and therefore have no knowledge of
slots and drives or Smartports. 

-michael - NadaNet 3.1 and AppleCrate II: http://home.comcast.net/~mjmahon