While the SMB1 uses sprite 0 hit of the coin sprite to split the screen under status bar, SMB2J needs external IRQ source.
* Various FDS ports - M2 counter
* Loopy's MMC3 port - A12 scanline counter
* Mario All Stars MMC5 hack - M2 counter
Why? Because FDS adapter has IRQ counter so the lazy programmers used it?
I thought SMB1 and SMB2J use the same engine, just with different levels/graphics
There appears to be one version without external IRQ hardware, but then the status bar is completely sticked to the background:
https://archive.org/details/youtube-M2-ovBQW978
-
Bonus question: Why does the SMB1 2 players hack (VRC6) also need IRQ counter?
* Various FDS ports - M2 counter
* Loopy's MMC3 port - A12 scanline counter
* Mario All Stars MMC5 hack - M2 counter
Why? Because FDS adapter has IRQ counter so the lazy programmers used it?
I thought SMB1 and SMB2J use the same engine, just with different levels/graphics
There appears to be one version without external IRQ hardware, but then the status bar is completely sticked to the background:
https://archive.org/details/youtube-M2-ovBQW978
-
Bonus question: Why does the SMB1 2 players hack (VRC6) also need IRQ counter?