C64 timing diagrams

sta write test

start:
	sei	    
end:
	nop
	nop
	nop
	nop
	sta $ffff
	nop
	nop
	nop
	jmp end

inc write test

start:
	sei	    
end:
	nop
	nop
	nop
	inc $ffff
	nop
	nop
	nop
	jmp end

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ROML timing