Midscanline CHR bank switch demo

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Midscanline CHR bank switch demo
by on (#103775)
My good old mid-scanline demo from 2009 uploaded again.

It shows how to change CHR-ROM banks mid-scanline to bypass the 256-tiles limitation. In this example it alternate between the playfield CHR bank and the letter's CHR bank, simulating what the MMC4 does by hardware in Fire Emblem.

I added a second variant of it which changes the low 3 bit of the scrolling by writes to $2005.1
It's less impressive though.

Comes with NTSC and PAL variants, all tested on hardware (powerpak).