PHY Noise CB (u8 channel, s8 noise)

1. If phynoise_state is zero

   1. Return

2. If phynoise_state & 0x1 is not zero

   1. If phynoise_chan_watchdog equals channel

      1. Set phynoise_window[phy_noise_index] to noise

      2. Set phy_noise_index to (phy_noise_index < 7) ? phy_noise_index + 1 : 0

   2. Clear bit 0x1 in phynoise_state

3. If phynoise_state & 0x2 is not zero

   1. If phynoise_chan_scan equals channel

      1. Set phy_noise_list[channel] to noise

   2. Clear bit 0x2 in phynoise_state

4. If phynoise_state & 0x4 is not zero

   1. Clear bit 0x4 in phynoise_state