POKE 1,0 would mess up the bank switching of addresses above $A000 and switch on the Datasette motor. Probably not what you wanted. I guess you meant POKE 646,1 (white text on black screen).

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weinzierl 2 hours ago | parent [-]

I memory serves me the sequence turns the screen black and POKE 1,0 hangs it. At least that is what I intended, maybe it was POKE 0,1?

	▲	nathell an hour ago \| parent [-]
		Ah, yeah, POKE 1,0 might plausibly have caused a hang. Sorry!