Constants:

6.11E6	(6.11MHz clock frequency)
2	(8085 divides it by two)
DIV
1/X	(Seconds per t-state)
STO 1

98
STO 2	(Fixed cost)

24
STO 3	(Variable cost)

Frequency Calculation
Input: Frequency in Hz
Output: Number of iterations of loop

LBL A
RCL 1
DIV
RCL 2
MINUS
RCL 3
DIV
RTN

Delay Length Calculation
Input: Delay in seconds
Output: Number of iterations of loop

LBL B
RCL 1
DIV
RCL 3
DIV
0.5
ADD
INT
RTN

Decimal To Hex Conversion
Input: Decimal number
Output: Hex digits, starting with most signifcant nibble.  10=A, 11=B, etc.

LBL C
65536	(Shift everything to the right of the decimal point)
DIV
LBL 1	(For each hex digit)
FRAC	(Discard the already displayed integer portion)
16	(Multiply by 16 to move the next digit to the left of the .)
MULT
ENTER	(Push a copy)
INT	(Chop off the other digits)
R/S	(Stop to show result to user)
Rdown	(Pop the copy)
GTO 2	(Do it again)