This menu lets you add custom RAM watches to observe arbitrary parts of game's memory in real-time. Pressing the plus icon will add a new watch, and pressing the cross next to a watch will remove that watch. After adding a watch, enter a memory address and value type to display the value at that address. These watch types are available:
- u8: one-byte value, unsigned.
- s8: one-byte value, signed.
- x8: one-byte value, hexadecimal.
- u16: two-byte value, unsigned.
- s16: two-byte value, signed.
- x16: two-byte value, hexadecimal.
- u32: four-byte value, unsigned.
- s32: four-byte value, signed.
- x32: four-byte value, hexadecimal.
- f32: four-byte value, IEEE 754 single-precision floating-point.
Pressing the anchor button next to a watch will release the watch from the watches menu so that it's always visible, even when the menu is closed. When a watch is released, a positioning button will appear which lets you change the position of the watch on the screen. Holding Z when positioning the watch will move it faster.
Watches can be imported from text files on an ED64 SD card by pressing the folder icon. Press a watch file to bring up a list of all watches contained in that file. Press a watch to import it to your watch list. When you've imported all the watches you need, press return to go back to the watches menu. The format of watch files is described in the wiki, here.