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PostPosted: Mon Mar 20, 2017 2:09 pm 
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lidnariq wrote:
Branches can go between 129 bytes forward and 126 bytes backwards, and 197 bytes forward is out of range.

Ah ok, thanks lidnariq!! :D Why is it limited to 129 bytes forward? It uses positive and negative numbers maybe... so oh ok, windows 10 calculator in programmer's mode is fantastic!! :D So if... how does that work? How does it differentiate between forwards and backwards? Well, it must use positive and negative numbers... I remember it using negative numbers when it went backwards. But 129 is 1000 0001 and 126 is 0111 1110... but it's confusing to me beyond the fact that those two numbers are inverses. Help? :) *NVM tepples answered!

tepples wrote:
That's 129 bytes forward or 126 bytes backward from the address of the branch instruction's opcode. The apparent imbalance is because the offset is actually measured from the address of the opcode that would be executed if the branch were not taken, and it has the typical range of an 8-bit signed integer: 127 bytes forward or 128 bytes backward.
Thank you so much tepples!! :D Makes sense! :) :mrgreen:

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found Loopy's new site (from Memblers) (through google): http://3dscapture.com/NES/


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