Frequency Control - Low-Byte
  |   <A HREF="SID1.HTM">$D401/54273/SID+1</A>       Voice 1: Frequency Control - High-Byte
  |   <A HREF="SID2.HTM">$D402/54274/SID+2</A>       Voice 1: Pulse Waveform Width - Low-Byte
  |   <A HREF="SID3.HTM">$D403/54275/SID+3</A>       Voice 1: Pulse Waveform Width - High-Nybble
  |   <A HREF="SID4.HTM">$D404/54276/SID+4</A>       Voice 1: Control Register
  |   <A HREF="SID5.HTM">$D405/54277/SID+5</A>       Voice 1: Attack / Decay Cycle Control
  |   <A HREF="SID6.HTM">$D406