To unlock the ASIC, a 17-byte "unlock" sequence must be sent to the CRTC's selection port (&BC00) :
RQ00, 0, 255, 119, 179, 81, 168, 212, 98, 57, 156, 70, 43, 21, 138, STATE, <ACQ>
* RQ00 must be different from the value 0.
* STATE=205 for UNLOCK otherwise another value for LOCK.
* ACQ represents sending any value if STATE=205 (not needed otherwise).
= Z80 Assembler version =
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