This is a macro used primarily in multipage applications.
This exits the application. Should be used in every application.
This jumps to an area of memory which "puts away" the application.
Two bytes representing a location in memory, or a label representing a location in memory.
As stated earlier, this serves as a JP or JR for multipage applications. As for exiting an application, brandonw recommends using a B_CALL instead.
If you wish to make a custom putAway for your App, you do need a B_JUMP.
PutAway is a special system call, which will not have its own page yet.
If bit 5, (IY + 25h) is set, nothing happens.