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konForce

changing first down yardage

11 posts in this topic

To change the amount of yards needed to gain a first down edit the byte at 0x24FDF. The default value is 0x50 (or 80 in decimal, 8 * 10). To change to 20 yards, change the value to 0xA0 (160 in decimal, 8 * 20). Each yard is worth 8 "points". Therefore, the possible range is 0 to 32 yards.

----Ignore this part-----------------

This does not update all aspects of the game. The chains still show up ten yards apart, and it says 1st and 10. If you gain 9.9 yards, the ref will measure anyway. If you gain over 10 yards and under the new yardage, it will be X down and 99. The game plays fine though. It appeared to affect both players, including the CPU. Obviously, the CPU has no clue that it now needs to gain more than 10 yards.

I ran out of time, but if somone wants to look for the other places that need to be changed, just keep searching in the 0x24000 bank for the number 0x50 that follows a logical opcode. A good thing to look for are the immediate compare opcodes: C9, E0 and C0. (Ie, any of those three codes mean the NES is going to look at the next byte and do something depending on what it is.)

----End Ignore-----------------

On second thought, probably only the chain measure will follow one of those three bytes because the other areas (distance from chain, 1st and X) probably are the result of some arithmetic.

Update #1

With arithmetic in mind, I found the chain markers. They are at 0x26471 and 0x2649B, using the same yardage system as above.

Update #2

And finally, to update the text '1st and X', change the value at 0x2E495 and 0x2E4C4.

These changes may or may not alter when the refs from bring out the chains. CPU may or may not be affected. When they see they need 20 yards, they may opt to pass more - despite being 1st down. However, itheir logic code may very well have a "x50" hardcoded somewhere that makes the CPU always think its 10 yards for a first down.

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Well there is a slight problem with doing this. It seems unless you use multiples of 10 tecmo gets a bit confused. Like if you make it 15 yards sometimes the sticks will be 14 yards apart other times they will be 16 yards apart.

The numeric value displayed is okay as far as yards left for a first down is concerned but the yaard markers are always off. So sometimes you will be past the sticks and not have a first down. OTher times you will be before the sticks yet have a first down.

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Apprently some kind of arithmetic error occurs when using 15 yards. Using 16 yards which isnt as pretty of a number works fine and there are no issues with the yardage markers.

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could you send me another rom with the RIGHT hack you BUTTHOLE

8)

or i could do it myself...

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Has anyone tried changing the values on the bytes that konforce indicated for the sideline chain markers?

I just shifted the values on these bytes and got no on-screen change of where the chains are located...

The other values are fine. But the markers don't move.

amrush

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Posted (edited)

I added this to my Rom but noticed that the ref is still measuring at 9.9 yards instead of 15.9 yards (Im using 1st and 16). Am I missing something or does the yard markers not update that part?

 

OK i guess after reading the post again that the animation does not realize the change. Is there a place I can edit to change that, or is there a way I can just remove the animation entirely if that can't be done? Any help is appreciated.

Edited by TheRaja

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Yes, there is a separate check for if the ref-chains animation should be done. I will post when i get chance

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