Someone asked on the previous discussion why there's no heap but no one answered and replies are locked out, so I'll answer here:
There's no heap on the SNES because the system has only one program running at all times (the game). There's no point using dynamic memory allocation when all of the memory on the system is available to the program, so you can just start writing to any valid, writeable address you want. Some addresses are, of course, not writeable (such as ROM space), and some addresses are not memory (memory-mapped IO) but that's not a problem.
The really nice thing about the SNES is that it uses a 24-bit address space instead of the 16-bit address space of the NES. Most NES games needed to use mapper chips to swap between different ROM banks since with 16 bits you can only address 64KB of memory at a time and many NES games were larger than that. Having 24 bits allows you to fit your game into far fewer ROM banks, greatly simplifying the programming model and making it much more realistic to use a high-level language like C#.
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Someone asked on the previous discussion why there's no heap but no one answered and replies are locked out, so I'll answer here:
There's no heap on the SNES because the system has only one program running at all times (the game). There's no point using dynamic memory allocation when all of the memory on the system is available to the program, so you can just start writing to any valid, writeable address you want. Some addresses are, of course, not writeable (such as ROM space), and some addresses are not memory (memory-mapped IO) but that's not a problem.
The really nice thing about the SNES is that it uses a 24-bit address space instead of the 16-bit address space of the NES. Most NES games needed to use mapper chips to swap between different ROM banks since with 16 bits you can only address 64KB of memory at a time and many NES games were larger than that. Having 24 bits allows you to fit your game into far fewer ROM banks, greatly simplifying the programming model and making it much more realistic to use a high-level language like C#.