Talk:APU Noise

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Curiously, the noise channel's frequency counter on the die isn't an ordinary counter - it's an 11-bit linear feedback shift register (with taps at the 9th and 11th bits); when I take the counter values from the on-die ROM and run the LFSR until the result is '10000000000', the cycle counts (for NTSC) match once multiplied by 2 (note that this means the PAL frequency for $1 is almost definitely wrong). --Quietust 04:58, 23 January 2011 (UTC)