rt Continous Time
R  Memory Register
A Alpha Register
L Last x Register
X Stack Register (Main LED)
Y Stack Register
Z Stack Register
T  Stack Register
5 Stack Register
6 Stack Register
7 Stack Register
8 Stack Register
9 Stack Register
0 Stack Register
.  Main LED as Fixed Decimal
S Main LED as Scientific Ntn.
E Main LED as Engineering
I Main LED as Integer
$ Main LED as Dollars
£ Main LED as Pounds
¥ Main LED as YEN
H Main LED as Hexadecimal
D Main LED as Dozenal
8 Main LED as Octal
B Main LED as Binary
T Main LED as Time
H Main LED as Hours:Minutes
D Main LED as Degrees
F Main LED as Feet/Inch
Y Main LED as Yard/Feet