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What does the note on the JMP instruction means?

Latest Updated:11/11/2004

Question:

(CPU)  The notes on use of the JMP instruction describe:
"When using the JMP instruction in indirect addressing mode, do not specify the last address on a page as an indirect address."
What does this mean? [2004/11/11]

Answer:

It means that an address of which the lower 8-bit address is "FFh" can not be specified as a memory address (indirect designation addresss) containing the jump destination.
In other words, JMP ($xxFF) cannot be executed.
In addition, JMP ($FF) cannot be executed in zero page indirect addressing mode. In this case, specify 2 bytes of memory containing the jump destination within the zero page area. (#104905)
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