HP HP-20S - Base Conversions and Base Arithmetic; Switching Number Bases

Base Conversions and
Base Arithmetic
The HP-20S enables you to switch between four number-base
modes—decimal, hexadecimal, octal, and binary. You can convert
numbers from one base to another and perform arithmetic operations
in any of the four bases. The HEX, OCT, and BIN annunciators indi-
cate the current (nondecimal) mode.
Switching Bases
To switch to a different base mode, press:
Mode Keys Annunciator
Hexadecimal (%] HEX
Octal a3 ocT
Decimal () None
Binary (] BIN
44 4: Base Conversions and Base Arithmetic