2018-12-17 16:01:23 +11:00
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# Save RAM (SRAM)
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* **Address Span:** `0xE00_0000` to `0xE00FFFF` (64k)
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The actual amount of SRAM available depends on your game pak, and the 64k figure
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is simply the maximum possible. A particular game pak might have less, and an
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emulator will likely let you have all 64k if you want.
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As with other portions of the address space, SRAM has some number of wait cycles
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per use. As with ROM, you can change the wait cycle settings via the `WAITCNT`
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register if the defaults don't work well for your game pak. See the ROM section
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for full details of how the `WAITCNT` register works.
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The game pak SRAM also has only an 8-bit bus, so have fun with that.
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The GBA Direct Memory Access (DMA) unit cannot access SRAM.
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2018-12-22 18:26:52 +11:00
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Also, you [should not write to SRAM with code executing from
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ROM](https://problemkaputt.de/gbatek.htm#gbacartbackupsramfram). Instead, you
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should move the code to WRAM and execute the save code from there. We'll cover
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how to handle that eventually.
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