vladitx wrote:
On May 7, 12:16 am, pau...@saaf.se (Paul Schlyter) wrote:
The Apple II monitor though has a source for true random numbers,
although
with only 16 bits of entropy. The source is a 16-bit counter which is
incremented each time the monitor input routine polls the keyboard for
a keypress.
The entropy is very low, not 16 bits at all. If I needed random
numbers from Apple II I wouldn't use more than a bit or two per KEYIN.
On the contrary, since the low byte rolls over in less than 5
milliseconds, and since any keypress made by a human has much
more than a 5ms variance, the low bits are essentially random.
If you doubt it, do a test.
And if the input is in response to a prompt that must be read
and responded to, then the variance is more than a second, so
that many bits of the high byte are also random.
-michael
NadaPong: Network game demo for Apple II computers!
Home page: http://members.aol.com/MJMahon/
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