[img]https://zxdemos.ru/oldforum/uploads/images/93/38aee12d2a3c7b13b9f1765fc824e984.gif[/img]
Total in line : 32 + 36 + 128 + 28 = 224 tacts
Total in frame: 16 lns + 64 lns + 192 lns + 48 lns = 320 lines

from begin of INT: 3584t + 14336t + 43008t + 10752t = 71680tacts
80 lines = 17920 tacts

Signal INT forms wrong, in this computer time from begin of INT till end of frame is 320 lines = 71680 tacts. Therefore, after INT comes, it is useless to output anything on screen in first 16 lines = 3584 tacts, because in this time ray is moving up ( backtracing ).

[img]https://zxdemos.ru/oldforum/uploads/images/93/aff47a646bcbeec92f793a9339961b9d.gif[/img]
Total in line : 40 + 24 + 128 + 32 = 224 tacts
Total in frame: 64 lns + 192 lns + 40 lns + 16 lns = 312 lines

from begin of INT: 14336t + 43008t + 8960t + 3584t = 69888tacts
from begin of INT till end of frame 296 lines or 66304 tacts.

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