FCEUX breakpoints: Difference between revisions

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(clueless figured it out)
 
(redirecting to FCEUX debugger)
 
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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.
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.
 
After the programmer had been staring at the problem for too long, a fox came and helped him.
 
# Address: <code>28</code>
# Click "Write"
# Memory: <code>CPU</code> (the default)
# 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.
 
== References ==
*[http://nesdev.parodius.com/bbs/viewtopic.php?p=75485#75485 Forum post]

Latest revision as of 18:31, 4 September 2012

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