HP 20b Business Consultant User manual

hp calculators
HP 20b Operating modes, clearing options
and error messages
Mode menu options
Begin/End mode
Adjusting display contrast
Clearing options
The reset menu
Number entry
Error messages

hp calculators
HP 20b Operating modes and clearing options
hp calculators - 2 - HP 20b Operating modes and clearing options - Version 1.0
Mode menu options
The HP 20b Mode function, accessed by pressing :u, allows users to customize the appearance and operation of
the HP 20b to suit themselves. Table 1-1 below indicates the options you can change in the Mode menu, and the default
settings, as when the HP-20b is in a new or reset state. When using this menu, you may exit the menu by pressing O.
Table 1-1 Mode Menu Settings
Setting Display Description
FIX= 2 Number of digits displayed to the right of the decimal point. Default is 2decimal places.
Key in the number of digits you want and press I, or press =until the number of digits
you want is displayed.
If you specify a value of -1 for FIX, the calculator displays numbers with the most appropriate
number of digits after the decimal point.
Tip: if you find you need to change the FIX setting often, use this shortcut
1. Press :and release it. Check that the shift key annunciator is displayed.
2. Press :again, and, without releasing it, press a key, 0through 9, that corresponds to
the desired FIX setting, of 0 through 9 digits. Note: pressing .selects FIX= -1 as described
above.
FIX settings for 10 and 11 are not available using this shortcut.
Degree or Radian Angular mode for trigonometric functions. Default is Degree.
Pressing Itoggles between these options.
Date:
mm dd yyyy or
dd mm yyyy
Format for dates. December 3, 2010 is entered as 12.032010 in mm dd yyyy format, or 3.122010
in dd mm yyyy format. Note the (.) in both formats separating the first and second groups.
Default is mm dd yyyy format.
Pressing I toggles between these options.
Note that when a date is displayed, a number between 1 and 7 is displayed at the right of the
display. This number indicates the day of the week corresponding to that date. Monday is 1 and
Sunday is 7. Note: in 360-day calendar mode (Cal.360), days of the week are displayed only if the
date is valid.
1.23 or 1,23 Selects decimal point or comma as decimal separator. Default is decimal point, 1.23
Pressing Itoggles between these options.
1000.00 or 1,000.00 or
1000,00 or 1.000,00 Selects thousands separator. Default is none, 1000.00. Pressing Icycles through these options.
Note: the 1000.00 and 1,000.00 options are only available if the decimal separator is set for point.
1000,00 and 1.000,00 are available only if the decimal separator is set for comma.
Chain, Algebraic, or
RPN Calculation mode. Default is Chain. Pressing Icycles through these options.
English, Français,
Deutch or Español Language settings for the messages. Default is English. Pressing Icycles through these options.
Actual or
Cal.360 Calendar options for bonds and dates. Cal.360 uses twelve 30-day months. Default is Actual. Pressing Itoggles between these options.
Annual or Semiannual Bond interest payment type. Default is Annual.
Pressing Itoggles between these options.

hp calculators
HP 20b Operating modes and clearing options
hp calculators - 3 - HP 20b Operating modes and clearing options - Version 1.0
Begin/End mode
A special mode setting relates to the solution of problems known as annuities. This mode tells the HP 20b to solve these
problems assuming that payments are made either at the beginning of a period or at the end of a period, which is why
this mode is called Begin / End mode. When the HP 20b is in Begin mode, the display will show the word BEG in the top
right corner of the screen. There is no indication in the HP 20b display when the calculator is in End mode, other than by
the absence of the word BEG.
This mode is changed using the shifted BEG and END functions. The begin mode is on the front of the Vkey and you
press :? to activate begin mode. The end mode is on the front of the Fkey and you press :] to activate
end mode. When in begin mode, the HP 20b display will show a small BEG annuniciator in the top right corner of the
screen. If you receive an unexpected result when solving an annuity problem, make sure that the calculator is in the
proper mode and try resolving the problem.
Adjusting display contrast
To adjust the brightness of the display, press and hold Owhile pressing the +or -keys. Each press of the
+or -keys slightly increases or decreases the contrast of the display.
Clearing options
Pressing Oone time cancels current number entries, mathematical operations, or a menu selection, in that order.
Pressing Orepeatedly, with multiple operations pending, cancels one operation at a time, from the latest to the
earliest. In algebraic or chain mode, to ensure nothing is pending at the start of a new calculation, press O twice.
The Reset menu
The Reset menu allows you to reset some, or all, of the menu items, variables, and registers to their default values. To
open the Reset menu, press :x. TVM displays on the top line. Press <repeatedly to scroll to a specific item.
If you select the command to reset all values, All , you will be prompted to confirm your choice. To reset, press I.
At the All Reset message, press Ito reset all data in the calculator or Oto cancel.
Pressing :x while working within a particular menu takes you directly to the item of the Reset menu that allows you
to reset that menu. Say, for example, you are working in the Bond menu and you wish to reset all your entries in the
Bond menu. From anywhere in the Bond menu, press :x. Bond displays on screen. At this prompt, pressing
Iresets the Bond menu and returns you to the last item you were working with in the Bond menu.
Since entering data in menus can represent a significant amount of work, when the reset commands for the cash flows,
statistics and delete all (Del.All? ) functions are used, you will be asked to confirm your choice. At the prompt, press
Ito confirm, or Oto cancel. Once cleared, press O to return to the cash flow or statistics menu.
Number entry
Enter numbers by pressing 0-9, ., the }key, and by entering an exponent by pressing :w.
To correct a number entry, press {. Each press of {erases the last digit or symbol entered, starting with the least
significant digit at the far right of the number. If you press { after a calculation, the least significant digit of the result

hp calculators
HP 20b Operating modes and clearing options
hp calculators - 4 - HP 20b Operating modes and clearing options - Version 1.0
will be deleted, with each successive press deleting another digit. Note: This will delete the least significant digit of the
number, which may not be the least significant digit displayed due to the chosen display setting.
TIP: This is perhaps the easiest way to see all the digits of a number, regardless of the chosen display format. Simply
press { after a calculation to see all the digits. Pressing O one time will exit this edit mode without clearing the
number in the display.
To enter a number in the display, press the digits successively. A number can have up to 12 digits. To change the sign
of a number from positive to negative, press }. Scientific notation is used to enter very large and very small numbers.
For example, to enter the number 1.2345123 in scientific notation, first enter the mantissa, 1.2345, then press: :w
and enter the number representing the exponent, 123. The exponent must have a value between -499 and +499.
Error messages
The table that follows shows the error messages that the HP 20b can produce and their meanings.
Error Message Cause or explanation
ER: Underflow The calculation generated an underflow (result of 0).
ER: x/0 Division by zero.
ER: 0/0 Zero divided by zero
ER:∞*0 Infinity multiplied by zero.
ER: ∞/∞Infinity divided by infinity.
ER:√(x<0) Square root of a negative number.
ER: LN (0) Attempted to take the natural log (LN) of 0.
ER: LN (x<0) Attempted to take the natural log (LN) of a negative number.
ER: ATrig(|x|>1) ASIN or ACOS of a number > 1.
ER: 1^ ∞Attempted calculation of 1^(+/- infinity)
ER: (x<0)^ ∞Attempted calculation of the infinite power of a negative number.
ER: ∞^0 Attempted calculation of +/-∞^0.
ER: ∞^(Frac) Attempted calculation of +/-∞^(non-integer y).
ER: (x<0)^(Frac) Attempted calculation of x^(non-integer y).
ER: Out of Bounds Input out of bounds.
ER: Invalid P/YR Returned by TVM functions if payments per year are invalid (<0 or non-integer).
ER: Invalid Input Returned by any functions if arguments are invalid for any reason.
ER: Invalid I% Returned by finance functions if I% is ≤-100%.
ER: No Solution Returned when there is no solution to the problem.
ER: Many or No Solutions Returned if there is no solution, or more than 1 solution to the problem.
ER: Many Solutions Returned when there are many solutions to the problem.
ER: Invalid N Returned by time value of money or amortization functions if the number of periods per
year definition is invalid.

hp calculators
HP 20b Operating modes and clearing options
hp calculators - 5 - HP 20b Operating modes and clearing options - Version 1.0
Error Message Cause or explanation
ER: User Abort Returned by long functions if user requests break.
ER: ∞Result Returned if the result is infinite.
ER: Insufficient Data Returned by statistics functions if there is insufficient data for analysis.
ER: No Payback Returned by payback function if there is no payback on this problem.
ER: Unique solution to IRR Not Found Returned if IRR tries to calculate a solution but cannot find it. User should supply a new
guess and try again.
ER: Stack Stack overflow.
ER: Parenthesis: An error linked to use of parentheses: unmatched, too many, etc.
ER: Insufficient Memory Insufficient memory.
ER: No Solution Found No solution found.