rngcalls = 0;
_a = 0;

function RNG()
_a = _a + 1;
if (_a == 3) then
    print(string.format("0x%02X, ", memory.readbyte(0x001E)));
    print(string.format("0x%02X, ", memory.readbyte(0x001F)));
    _a = 0;
    rngcalls = rngcalls + 1;
    end;

end;

while (true) do
  memory.register(0x001F, RNG);
  gui.text(10,10, string.format("RNG CALLS: %2d", rngcalls));
  FCEU.frameadvance();
end;