Re: mass storage for Apple //c

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

Riccardo <rigreco.grc@gmail.com> wrote:
> Il giorno martedì 21 maggio 2013 07:05:04 UTC+2, Ivan X ha scritto:
>> On Monday, May 20, 2013 2:09:06 PM UTC-4, Riccardo wrote:
>> 
>>>> I'm kind of excited about this. And the Raspberry Pi model A (the $25
>>>> one with only a single USB and no Ethernet) can supposedly be powered
>>>> with 5v 300 mA, which makes me wonder if the 12v 300 mA pin on the //c
>>>> video expansion port can be used with some sort of device to reduce
>>>> the voltage, and then the Pi becomes a true self-contained storage
>>>> device for the //c. (I'm completely clueless when it comes to
>>>> electricity, so I don't know how viable this is.)
>> 
>>> 
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>> 
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>> 
>>> You can use +5V - GND from: External disk port, Game port or direct
>>> from internal power supply grid by two wires (but is a rough work to see).
>> 
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>>> Ric.
>> 
>> 
>> 
>> There's an excellent idea. I know Apple says that you're not supposed to
>> draw more than 100 mA from the +5V pin on the game port -- does anyone
>> have any idea what the max current available from the +5V pin on the disk connector is?
> 
> The Maximum supply currents from internal converter are:
> 
> (Max Total power is 25 W)
> 
> +5V --> 1.5 A
> +12V --> 0.6 A
> 
> - Be careful! If the currents are over this limits for few millisecond it
> can be like a short circuit and damage the circuits of the internal converter - 
> 
> (see pag. 234 of Apple IIc Technical Reference Manual)
> 
> Ric.

The supply has internal protection. It will probably work fine--just give
it a try. 

-michael (http://home.comcast.net/~mjmahon)