Question about Memory addresses

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Question about Memory addresses

kostya3312
1) What should be the behavior of the Memory chip if program will try to load some value by not allowed addresses ( > 24576 ) ?
2) Why there is a possibility to load value by address 24576 (keyboard). Specification of Keyboard chip says that it hasn't input.
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Re: Question about Memory addresses

cadet1620
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kostya3312 wrote
1) What should be the behavior of the Memory chip if program will try to load some value by not allowed addresses ( > 24576 ) ?
That behavior is unspecified, anything can happen.  Most students return the Keyboard value for values 24576-32767.
2) Why there is a possibility to load value by address 24576 (keyboard). Specification of Keyboard chip says that it hasn't input.
I think that you are confusing directions. The Keyboard chip has an output which is connected to the Memoy's output when reading address 24576. The Keyboard chip has no input, so there is no place to store anything if there is a write to memory address 24576.

--Mark
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