Simply put, what are the MMC5's capabilities? Here is my doubtless inaccurate list. I know it can support 1MB of PRG-ROM in 32, 16 or 8KB banks. It can switch CHR-ROM in 8,4,2 or 1KB banks. According to the mapper document it can support 512KB for background tiles and 2MB for sprite tiles, separately. It supports two extra pulse and one PCM sound channels. It can do 4-screen nametable mirroring if extra VRAM is on the board. It supports up to 64KB of W-RAM.
It also has a built-in multiplier to speed up mathematical calculations (how often do programs multiply?) It has three graphic extension modes, ExGrafix, ExRAM and Split Screen Mode. ExRAM is 1KB in the chip. ExGrafix can extend the selection of background tiles from 256 to 16384 and allows the programmer to eliminate the attribute table limitations on background colors. Split screen allows multiple sets of nametables to be used and can be enabled after any horizontal tile. The chip uses scanline-based IRQs.
It also has a built-in multiplier to speed up mathematical calculations (how often do programs multiply?) It has three graphic extension modes, ExGrafix, ExRAM and Split Screen Mode. ExRAM is 1KB in the chip. ExGrafix can extend the selection of background tiles from 256 to 16384 and allows the programmer to eliminate the attribute table limitations on background colors. Split screen allows multiple sets of nametables to be used and can be enabled after any horizontal tile. The chip uses scanline-based IRQs.