Recognized flags:
Value	Name			  Set			  Clear
0800  OF  Overflow Flag		OV  Overflow		NV  No overflow
0400  DF  Direction Flag	DN  Down		UP  Up
0200  IF  Interrupt Flag	EI  Enable interrupts	DI  Disable interrupts
0080  SF  Sign Flag		NG  Negative		PL  Plus
0040  ZF  Zero Flag		ZR  Zero		NZ  Not zero
0010  AF  Auxiliary Flag	AC  Auxiliary carry	NA  No auxiliary carry
0004  PF  Parity Flag		PE  Parity even		PO  Parity odd
0001  CF  Carry Flag		CY  Carry		NC  No carry

The short names of the flag states are displayed when dumping registers
and can be entered to modify the symbolic F register with R. The short
names of the flags can be modified by R.
