Author Topic: ...Breakpoints?  (Read 1560 times)

justin3009

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...Breakpoints?
« on: September 24, 2008, 09:26:58 am »
I get the basic concept of breakpoints, but I'm lost when it gets farther. 

How exactly do you figure out breakpoints?
How do you know whether to use Execute, Write, or Read?

Those are pretty much the things that are getting me.

syntax error

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Re: ...Breakpoints?
« Reply #1 on: September 24, 2008, 11:26:02 am »
simplest case is read.

If you want to get the ROM address of a constant that you know,search for the value and note all
occurrences.Then set read breakpoints to them and if you see if the code reads from this address at a well known situation
,then you know that if you change this value the game sets a variable via "LDA ####" instruction.

(sorry I need to buy a drink)

Vehek

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Re: ...Breakpoints?
« Reply #2 on: September 25, 2008, 01:58:35 am »
I generally use read breakpoints to find when the game loads a ROM or RAM location I already know.
I use execute breakpoints to see what some code I found will do under different situations, or to find out what code leads to an instruction I found with a read or write breakpoint.
Generally, write breakpoints are used when you want to find when it copies something into memory.