Mode 7 Force Blank test rom #431
Description
Two different test roms. One with Force Blank through Vblank and one with short Force Blank in the middle of the screen.
You can see that if Force Blank goes through Hblank then the next line always starts at the top left tile of the Tile map. This is because during VBlank and Force Blank the multiplier is set to M7A * (M7B[15:8] * 8) and M7B is initially 0000 in this rom.
After Force Blank is disabled the first few pixels are from color $FF (Purple) and then there are 3 pixels where it still read the pixels with multiplier set to the Force Blank multiplier.
With PR #429 the behavior is the same as original hardware.
Controls:
L/R: Move IRQ
Left/Right: Change M7A
Start+Y/A: Change M7B
Start+X/B: Change M7C
Up/Down: Change M7D
Start+Left/Right: Change M7X
Start+Up/Down: Change M7Y
Y/A : Change H Scroll
X/B: Change V Scroll
Videos from original hardware:
Vblank:
https://youtu.be/6i5YUSRnVwY
Short FB:
https://youtu.be/cwwKOOZn3CE