Battery Backed RAM
A real Pro 350 has 50 bytes of battery-backed RAM.  Xhomer emulates this RAM with a
100 byte file (half of the bytes are unused), called "bat.ram."  If this file is
found in the current directory, when Xhomer is invoked, it is loaded.  If it is not
found, then the emulator's 50 bytes of internal RAM are cleared.  Upon exit, the
emulator writes the contents of its emulated battery-backed RAM back out to
"bat.ram."