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Re: A few technical q's from an apple newbie

Mark McDougall wrote:

Hi Joseph,


The Apple II,II+,IIe do not have a periodic IRQ. The IIc has IRQs


    (snip snip)


decoding was incomplete, and the same RAM location could have multiple
addresses.)



Thanks for that info - very helpful and very much appreciated!!!
Now I just need to know which characters were flashing, but I'm sure I'll find that info *somewhere* on the net... 

Regards,



On the stock ][ and ][+,

Values 0-31 are ASCII codes 64-95 inverted
Values 32-63 are ASCII codes 32-63 inverted
Values 64-95 are ASCII codes 64-95 flashing
Values 96-127 are ASCII codes 32-63 flashing
Values 128-159 are ASCII codes 64-95 normal
Values 160-191 are ASCII codes 32-63 normal
Values 192-223 are ASCII codes 64-95 normal
Values 224-256 are ASCII codes 32-63 normal, or with an expansion kit installed, ASCII codes 96-127 normal. 127 is the checkerboard (like on the //e and later).
On the //e a softswitch toggles between flashing uppercase/symbol and mousetext/inverse lowercase; I can't remember which one this is. 

Moll.