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6502.txt twos complement[edit]

Various places in the 6502.txt document that refer to negative numbers don't seem to realize that it's 6502 uses twos complement - not just a simple sign bit. This is semantically important, for example in the section about branch instructions it states that they have a range of 127 forward and backward - this is inaccurate, twos complement represents 128 values backwards (which is its advantage over a simple sign bit representation, which loses a bit by representing +0 and -0).

Registers article[edit]

Creating an article describing the registers as this seems to be a blindspot in the Wiki. alphamule (talk) 02:09, 20 February 2015 (MST)

PAL frequency formula[edit]

15625 Hz * 283.75 + 25 Hz = 4433618.75 Hz