Ah, right.
Anyway, buttons (1/x), (x^2), and 3,6,9 don't work right on my ti1270 emulation. I checked the bits on the die pic under the smudge for faults. I found 1 bad bit! But frown seems to have no effect at all on the emulation.

ti1270raw.bin offset $174, change $11 to $51.