Talk:CPU: Difference between revisions

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== 6502.txt twos complement ==
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 ==
== Registers article ==



Latest revision as of 21:00, 2 January 2018

6502.txt twos complement

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

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

15625 Hz * 283.75 + 25 Hz = 4433618.75 Hz

source: https://de.wikipedia.org/wiki/Phase_Alternating_Line#Wahl_der_PAL-Farbtr.C3.A4gerfrequenz