HP-91 Simulator

[Joe Horn]

'Nuther bug: The three LIST commands (e.g. LIST STACK) don't work in MAN mode. "LIST" is printed, then nothing else.

And another one: -1E-10 prints as -0 in any FIX setting.

And -5.6E-78 displays ok in SCI 2 mode, but ENG 2 mode displays it as -5.6E-22.