Changes
CRTC
,Type 2
{|{{Prettytable|width: 700px; font-size: 2em;}}|''b1 ''||''b0 ''||''Function ''||''Read/Write '' |-|0 ||0 ||Select internal 6845 register ||Write Only |-|0 ||1 ||Write to selected internal 6845 register ||Write Only |-|1 ||0 ||- ||- |-|1 ||1 ||Read from selected internal 6845 register ||Read only |-|}
Type 3 and 4
{|{{Prettytable|width: 700px; font-size: 2em;}}|''b1 ''||''b0 ''||''Function ''||''Read/Write '' |-|0 ||0 ||Select internal 6845 register ||Write Only |-|0 ||1 ||Write to selected internal 6845 register ||Write Only |-|1 ||0 ||Read from selected internal 6845 register ||Read Only |-|1 ||1 ||Read from selected internal 6845 register ||Read only |-|}
It is not possible to read from all the internal registers, this table shows the read/write status of each register for each type:
