I know that it is very glitchy, especially when its output is connected to a high capacitance or low resistance load, but how is it getting the numbers "-5V", and "-4V"? I think it should give -2V, and 2V, or possibly 2V, and 4V, since it has its own internal ground (as you can see if you look at the output pin giving 0V as the "low", instead of the realistic -6V).
