Gotchas: Difference between revisions
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→JP (HL)
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=={{header|Z80 Assembly}}==
===JP (HL) Does Not Dereference===
For every other instruction, parentheses indicate a dereference of a pointer.
<lang Z80>LD HL,(&C000) ;load the word at address &C000 into HL
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JP (HL) ;set the program counter equal to HL. Nothing is loaded from memory pointed to by HL.</lang>
This syntax is misleading since nothing is being dereferenced. For example, if HL equals &8000, then <code>JP (HL)</code> effectively becomes <code>JP &8000</code>. It doesn't matter what bytes are stored at &8000-&8001. In other words, <code>JP (HL)</code> ''does not dereference.''
Strangely enough, [[8080 Assembly]] uses a more sensible <code>PCHL</code> (set Program Counter equal to HL) to describe this function. So this gotcha is actually exclusive to Z80.
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