* Input
{|{{Prettytable|width: 700px; font-size: 2em;}}class="wikitable"|''!Bit''||''!Description''||''!Usage in CPC''||''!Usage in KC Compact''
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|7||CAS.IN||Cassette data input||Same as on CPC
* upper: output, lower: output
{|{{Prettytable|width: 700px; font-size: 2em;}}class="wikitable"|''!Bit''||''!Description''||''!Usage''
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|7||PSG BDIR||PSG function selection
PSG function selection:
{|{{Prettytable|width: 700px; font-size: 2em;}}class="wikitable"|''!Bit 7''||''!Bit 6''||''!Function''
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|0||0||Inactive