hw6_solution - ECE331 SS-08 HOMEWORK #6 Solution Problems...

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ECE331 SS-08 HOMEWORK #6 Solution Problems from the textbook Chapter 2: Fundamental: 1. Memory mapped I/O partitions the address space into memory portion and I/O port portion. Advantages: Instructions used for operating on memory can be used. Also, no extra pins required. Disadvantages : Loss of memory space. In Isolated I/O, extra pin determines whether the address bus value is meant as the memory or I/O address. Advantages: Large I/O space. Disadvantages: Extra pin required. Separate instructions required for I/O. 2. DDRC establishes the directionality of a bi-directional port. For pins 6 and 7 as input, load $3F into the DDRC. The address of DDRC is $0006. 3. Fundamental-6: The stack is an invaluable tool for temporary storage for cases illustrated in the problem. By storing the contents of the accumulator to the stack and retrieving them after required instructions are processed, we can safely restore the accumulator contents. The required instructions before the subroutine are PSHA, PSHB and PSHY. The necessary instructions after
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This note was uploaded on 03/24/2008 for the course EGR 331 taught by Professor Jayanthirao during the Spring '08 term at Michigan State University.

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hw6_solution - ECE331 SS-08 HOMEWORK #6 Solution Problems...

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