Megadrive and ASM68k - having trouble with absolute basics

the VDP has 64kB of VRAM, so everything not used by the sprite table, the Hscroll data, PlaneA and B tables is free for the tile generator. In your case from 0 to BFFF and some free spots between the tables.

You can check the VRAM utilisation on regen's VDP debugger (also gens)

 

I noticed all the problems up above with there being junk data the beginning of the file. Simple simple fix. Stick a /p in the commandline for asm68k. Output's a Pure binary rather than whatever format asm68k outputs for the accessory programs that are part of the PsyQ set for MegaDrive.

 

Ahh I see, some sort of metadata for the debugger, I presume?