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| Once upon a time, an NES programmer was trying to determine where in the code a screwed up value was being written to a specific memory location.
| | #REDIRECT [[FCEUX debugger]] |
| Specifically, when the value $EE was being written to location $0028.
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| To figure out what can be put into the "condition" text input field in the breakpoint dialog box, he dug into the source code for FCEUX and found [http://fceux.sourcearchive.com/documentation/2.1.4aplus-prepack-0ubuntu1/conddebug_8cpp-source.html the parser], whose grammar is listed near the top of the source file.
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| After the programmer had been staring at the problem for too long, a fox came and helped him.
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| # Address: <code>28</code>
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| # Click "Write"
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| # Memory: <code>CPU</code> (the default)
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| # Condition: <code>R == #ee</code> if you don't know what CPU register is used for the write or <code>X == #ee</code> if you know it's X. The # is important; leaving it out will screw it up.
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| == References ==
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| *[http://forums.nesdev.org/viewtopic.php?p=75485#p75485 Forum post]
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