Jump to content

Need Help With Hacking Robot Tank, Please

Jamcat Reloaded

Recommended Posts

I want to do a hack of Activision's Robot Tank. I want to change the "TANK" text sprite to another word. Using Bithacker, I was able to find where the "TANK" text is in the code, but part of the "T" is missing. I've attached a image below. The red boxes show most of the word, and just a part of the "T" in the code. The blue boxes show the rest of the "T" graphic that is missing. Nothing above lines up to match the missing part segment of the "T". So with that, might anybody know where the missing "T" segment might be in the code? Thanks!



Link to comment
Share on other sites

Use Stella's debugger to find stuff:


First, enter the debugger when the gfx you want are onscreen. Right-click the image at the height of where it appears and choose "fill to scanline". The disassembly window will then be displaying the routine that draws the image onscreen. From the screenshot below, you can see that the routine is grabbing its sprite values from indirect addresses 86-87, 88-89, 8a-8b, 8c-8d, 8e-8f, and 90-91. The left half of T (i.e. the second sprite to be displayed on each scanline) is fetched from ram addresses 88-89...which hold the vector $FEB0. $0Eb0 in a bithacker.


Link to comment
Share on other sites

Yes, I found out the text "BONUS" shares letters "O" and "N" with the text "SQUADRON". So I just replaced "SQUADRON" with "RAID" and changed the "B" to a "+".


As for the section of "T" in the "TANK" text, I couldn't find it. So I made do and just turned the other half of the "T" into a "A".


I was tempted to say hell with it and leave the "TANK" text, but I know somebody would have said "If you're supposed to be driving a car, why does it say tank???".

Link to comment
Share on other sites

As for the section of "T" in the "TANK" text, I couldn't find it.



Same page you quoted...just a bit further down.


Notice that all the surrounding bytes have the low bit set, tho. Makes me suspect that this entire area is shared to do something else, too. Keep the rightmost bit set if you do change them, I'd guess.


Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Recently Browsing   0 members

    • No registered users viewing this page.
  • Create New...