Cheat Engine

[Outlivinglife]

I've made several hacks (and even some moderately sophisticated ones) to several video games (including those on NES), but this games is apparently unhackable or something. As I understand it, cheat engine looks for hex written to RAM, so theoretically I should be able to find something like the number "0" (or 00 in hex) if the number 0 is written to the game, but this just doesn't appear to be the case. Let me explain.

I have 0 goods when I start the game. So I attach cheat engine, search for 0, and get a plethora of results. To ensure I'm getting the RAM location I'm looking for, I decided to go as broad as possible searching for All types. I then purchase a single good (1 ton) from the merchant and notice in-game that the 0 turns to a 1. Again, to go as broad as possible, I simply select "Changed" value. I sell that single ton to return back down to 0, selecting "Changed" again, and rinsed and repeated several times to dwindle down my results. This got me to about 800 or so.

There were some other changes as goods increase (such as cargo space decreasing and gold decreasing), so I eliminated those by purchasing sugar and searching for unchanged values and then selling the sugar and, again, searching for unchanged values. This got me to about 100 results or so.

I then added all 100 of those codes to my list, activated them all and purchased a good, expecting my 0 to remain at 0, but this was not the case. There appears to be something else governing what's being written to the screen, but this level of programming is far beyond the basics.

If you're looking for a challenge, I suggest trying to crack this nut. Or if you just want to help me out with this, that would be fantastic as well.

BTW, I'm using FCEUX 2.1.1 NES emulator and you can find the Pirates! ROM that I'm using at DopeRoms (filename: Pirates! (U) [o1], although I'm sure all of the Pirates! games would likely act the same way).

[Dark Byte]

go to settings scan settings and confirm 1 byte is part of all
if not (e.g if 4 byte is the smallest type selected) then when you do an unchanged scan but the bytes in front and behind have changed it won't be found

[Outlivinglife]

I didn't see that setting (maybe my Cheat Engine is out-of-date -- using 6.4), but I did see a setting "MEM_MAPPED:Memory that is mapped into the view of a section." (E.g.:File mapping, emulator memory, slow)", and it seemed to work after I checked that one.