Emulator Cheats

Posted: **Fri Feb 04, 2011 1:17 pm**

[Modified with suggestions made in post below]

This alters ghost/monster behavior to allow travel up the passages they normally are restricted from using:

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:puckman:20800000:1C15:00000000:FFFFFFFF:Ghosts Go Up All Passages
:puckman:20810000:1CEC:00000000:FFFFFFFF:Ghosts Go Up All Passages (2/4)
:puckman:20810000:1DC3:00000000:FFFFFFFF:Ghosts Go Up All Passages (3/4)
:puckman:20810000:1E9A:00000000:FFFFFFFF:Ghosts Go Up All Passages (4/4)

Here is the XML version also:

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  <cheat desc="Ghosts Go Up All Passages"> <comment>Ghosts can travel up restricted passages in chase/scatter modes</comment>
    <script state="on">
      <action>temp0 =maincpu.mb@1C15</action>
      <action>temp1 =maincpu.mb@1CEC</action>
      <action>temp2 =maincpu.mb@1DC3</action>
      <action>temp3 =maincpu.mb@1E9A</action>
    </script>
    <script state="run">
      <action>maincpu.mb@1C15=00</action>
      <action>maincpu.mb@1CEC=00</action>
      <action>maincpu.mb@1DC3=00</action>
      <action>maincpu.mb@1E9A=00</action>
    </script>
    <script state="off">
      <action>maincpu.mb@1C15=temp0 </action>
      <action>maincpu.mb@1CEC=temp1 </action>
      <action>maincpu.mb@1DC3=temp2 </action>
      <action>maincpu.mb@1E9A=temp3 </action>
    </script>
  </cheat>

This isn't a "cheat", per se -- more an interesting modification for tougher gameplay. Ghosts are normally not allowed to go up the two passages directly above where Pac-Man starts each level or the two passages directly above the monster pen. Removing this restriction definitely makes the game more challenging and renders any existing patterns useless (it also makes the classic "hiding spot" useless) -- ghosts can now go anywhere Pac-Man can go. You can observe the difference in demo/attract mode as the red/pink ghost will immediately go up the previously forbidden passages during their first scatter mode.

It has been tested with the puckman, pacman, puckmanf, and pacmanf ROM sets but should work with most any clone of Puckman.

Posted: **Mon Feb 07, 2011 1:03 am**

Nice & Interesting site there.

The .dat cheats posted don't match the .xml cheats. The dat cheats are poking bytes and the XML cheats are poking words, the dat cheats are not ideal because they NOP the branch instruction but leave the offset set to 3. You could just zero the branch offset like so:-

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:puckman:20800000:1C15:00000000:FFFFFFFF:Ghosts Enter All Passages:This can lead to a much harder game, Ghosts can travel up restricted passages in chase/scatter modes
:puckman:20810000:1CEC:00000000:FFFFFFFF:Ghosts Enter All Passages (2/4)
:puckman:20810000:1DC3:00000000:FFFFFFFF:Ghosts Enter All Passages (3/4)
:puckman:20810000:1E9A:00000000:FFFFFFFF:Ghosts Enter All Passages (4/4)

Anyway I digress, nice codes I'll add them to the next update - thanks.

Posted: **Mon Feb 07, 2011 3:34 am**

Pugsy wrote:The .dat cheats posted don't match the .xml cheats. The dat cheats are poking bytes and the XML cheats are poking words, the dat cheats are not ideal because they NOP the branch instruction but leave the offset set to 3.

You are quite correct and thanks for pointing that out. This is my first time messing with the cheat engine/syntax and I didn't realize I had left a discrepancy between the .dat and .xml versions. I also agree it makes the most sense just to zero out the branch offset and I will edit my original post to reflect these changes for both .dat and .xml.

-J

Emulator Cheats

[puckman]+ Ghosts go up restricted passages

[puckman]+ Ghosts go up restricted passages

Re: [puckman]+ Ghosts go up restricted passages

Re: [puckman]+ Ghosts go up restricted passages