Changes
CRTC
,/* CRTC Differences */
* On types 0 and 1, if a Write Only register is read from, "0" is returned.
* CRTC types 3 and 4 are identical in every way, except for the unlocking mechanism , split-screen and the 8-bit printer port functionalities specific to the ASIC.
* See the document "Extra CPC Plus Hardware Information" for more details.