Update notes.md

src/content/docs/dev/notes.md

@@ -13,14 +13,20 @@ Here's some of the mapping I know about :
 
 - `0xA405_0100` may be the touchscreen, where `0xA405_01F3` changes when screen it touched
 
-- RAM is `0x8c00_0000`
+- RAM is `0x8c00_0000` to `0x8cff_ffff`
 
-- ROM is `0x8000_0000` to `0x81ff_ffff`
+- MCS starts at `0x8e00_0000`
+
+- ROM is `0x8000_0000` to `0x81ff_ffff` 
 
 - Cached rom is `0xa000_0000` to `0xa1ff_ffff`
 
 - Display DMAC start at `0xb400_0000`
 
 - There are some "direct Io" from `0xFEC0_0000` to `0xFEFF_FFFF`
 
-When loading a .bin program, it is copied at `0x8cff_0000` and the PC jump to this offset
+## RAM
+
+When [loading a .bin program](https://github.com/SnailMath/hollyhock-2/blob/master/launcher/bins.cpp#L178), it is copied at `0x8cff_0000` and the PC jump to this offset 
+
+> For hollyhock, we usually use the end of the ram, that space is usually occupied by the mcs file system, but if it's not fully full, then it should work. Just note that the hollyhock launcher is running from ram, so it can't overwrite itself...`8C00_0000` to `8CFF_FFFF` is ram, we use [`8CFE_0000`](https://github.com/SnailMath/hollyhock-2/blob/master/patches/file_loader/file_loader.s#L134) for the launcher (from the run.bin file) and [`8CFF_0000`](https://github.com/SnailMath/hollyhock-2/blob/master/launcher/bins.cpp#L178) for [programs](https://github.com/TheRainbowPhoenix/CPAppTemplate/blob/main/linker_bin.ld#L4), just look at the launcher how big it is, you can squeeze out a bit if you start your program at `8CFE_8000`....