* for reading data from PSG all bits must be set to input (thereafter, output direction should be restored, for compatibility with the BIOS).
{|{{Prettytable|width: 700px; font-size: 2em;}}class="wikitable"|''!Bit''||''!Description''||''!Usage''
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|7-0||PSG.DATA||[[PSG]] Databus (Sound/Keyboard/Joystick)