1:Breakpoint is set. ($38 Read and Write)

2:You jump into the hole.
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3:Processing stops by breakpoint.($38)
4:And, you add breakpoint. . ($37 Read and Write)
5:You click "Run".

6:Processing stops by breakpoint.($37)
7:You rewrite A register and Y register to "FF".(The test of  delay and down scroll)

8:If you are "Run" or "Close" clicked, the scroll in the under is caused.
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Processing named NMI is called by delay in the timing of 7 and Y register becomes FF from 04 in this place.
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