Re: mass storage for Apple //c

[osgeld <kevin@hackaday.com>]

On Monday, June 10, 2013 4:24:08 PM UTC-5, Riccardo wrote:
> Il giorno martedì 21 maggio 2013 07:05:04 UTC+2, Ivan X ha scritto:
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> > On Monday, May 20, 2013 2:09:06 PM UTC-4, Riccardo wrote:
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> > > > 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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> > > 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.
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> > 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?
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> The Maximum supply currents from internal converter are:
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> (Max Total power is 25 W)
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> +5V --> 1.5 A
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> +12V --> 0.6 A
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> - 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 - 
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> (see pag. 234 of Apple IIc Technical Reference Manual)
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> Ric.

yea I guess the question is how much the computer draws at worst case off the 5 volt rail (floppy disk running, sound full blast, etc) since 1.5 amps is pretty beefy, but everything except the disk drive motors run off of 5 volts