determining tile number when editing large helmets?

[ren6175]

Ok, I learned alot of this from asking questions and reading the romhacking.net docs. I know where all the pointers and data are stored for the large helmets. So, lets say I want to put the logo in for a team that isn't there already. I know how to use tile editor to insert the logo. I also understand how the grid works so that I can determine the locations and order for putting together the logo. I know there are 5 banks for storing the large helmet logos.

Consider this example taken from jstout's large helmet editing sticky...

Example: Lets change Houston's logo. Replace their line with:

9E 3D 1E 01 34 05 36 9F 3D 1F 01 35 05 37 80 3D 39 01 3C 05 3D FF. The logo should have the base legs to the right of the upper section. Go ahead and put it back after you looked.

How did he know that tile 1E, tile 34, tile 36, etc were the correct tiles within that bank?

My question is how do I determine the tile number within each bank? Or also, how do I determine where each bank starts? (I know they are numbered 00 to 3F)

Tile editor gives me an absolute hex address within the ROM, but when I am looking at the tiles I need to know which one contains my image so I can draw it using the grid.

Thanks.

[jstout]

To be technical for a second, the NES has a tile section for sprites and backgrounds. TSB will either be 2 2KB banks or 4 1KB banks in those.

CHR ROM bank configuration:

(0: two 2 KB banks at $0000-$0FFF, four 1 KB banks at $1000-$1FFF;

or

1: four 1 KB banks at $0000-$0FFF, two 2 KB banks at $1000-$1FFF)

The 2KB banks will be split into tiles 00-7F and 80-FF. The 1KB banks will be split into tiles 00-3F, 40-7F, 80-BF, and C0-FF.

Ok, now for the rest. The game determines banks by numbers that always have the same size. From the first tile in the game (x40010) every 64 tiles is a 1KB bank. Every bank is always in order as in a tile editor (no random setups).

To find the tile number, you can do it the old fashioned way (change the tile number until you find one you can use for comparison) or use a PPU Viewer. A PPU viewer is in some emulators (FCEUXD is the one I use). When at a screen with the tiles you want, you would open the PPU Viewer and it will show the current tiles loaded (when you select (or move the curser) on a tile there the number is displayed.

[ren6175]

Ok, that's sort of what I thought although I appreciate the explanation. I didn't realize the how the 1kb banks were split into 4 different sections. I was looking at the tiles in the PPU viewer, but the tile number I was looking for said 80. I thought the number had to be between 00-3f so I was confused.

The 2KB banks will be split into tiles 00-7F and 80-FF. The 1KB banks will be split into tiles 00-3F, 40-7F, 80-BF, and C0-FF.

This sentence was very helpful.

As usual, you gave me a quick, helpful answer. Thank you.