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RPN Financial 12 manual · Chapter 1 of 16

Getting started

The display, the f and g prefix keys, the first RPN calculation, correcting mistakes and typing with a computer keyboard.

1.1What this calculator is for#

Anatomy of RPN Financial 12: the display and the keys you will use most. The display shows:  0.00 /  0.00 /  0.00 /  0.00.
Anatomy of RPN Financial 12: the display and the keys you will use most.
  1. Display: shows X, the number you work on
  2. n: number of periods
  3. i: interest rate per period (percent)
  4. PV: present value (the amount now)
  5. PMT: the regular payment
  6. FV: future value (the amount at the end)
  7. ENTER: separates two numbers
  8. f: gold prefix (the functions printed above the keys)
  9. g: blue prefix (the functions printed below the keys)
  10. CLx: clear the number in X

RPN Financial 12 is built for money problems. Loan payments, savings goals, leases, mortgages, bond prices and project returns are each solved with a few keys, and you can see every step of the working.

Underneath, it is an RPN calculator with a four-level stack. If you have not used RPN before, read the chapter "How RPN and the stack work" first. It takes ten minutes and then everything else is easy.

See also How RPN and the stack workHow the RPN stack works

1.2The display and its indicators#

The display shows the number in the X register: up to ten digits and a minus sign. Large numbers are grouped with commas, for example 1,234.56. The app also shows Y, Z and T above X.

The default format shows two decimals (FIX 2), which suits money. The display only shows two decimals. The calculator keeps more digits inside, so repeated calculations do not lose accuracy.

IndicatorMeaning
fThe gold prefix was pressed. The next key does its gold function.
gThe blue prefix was pressed. The next key does its blue function.
BEGINPayments are at the beginning of each period (annuity due). Without it, payments are at the end.
D.MYDates are keyed day first. Without it, dates are keyed month first.
CCompound interest is used for a part period at the start.
PRGMProgram mode is on. Keys are recorded as program lines instead of being run.
Error nA calculation could not be done. Press any key to clear it. See the Errors chapter.
While typing: the display shows exactly what you have keyed in. The display shows:  0.00 /  0.00 /  0.00 /  1,234.50 /  1,234.5.
While typing: the display shows exactly what you have keyed in.
After an operation: the result in FIX 2 (the square root of 2). The display shows:  0.00 /  0.00 /  0.00 /  1.41.
After an operation: the result in FIX 2 (the square root of 2).
An error: 1 divided by 0 shows Error 0. Press any key to clear it. The display shows:   Error 0 /  0.00 /  0.00 /  0.00 /  0.00.
An error: 1 divided by 0 shows Error 0. Press any key to clear it.

1.3The f and g prefix keys#

Most keys do up to three jobs. The main job is printed on the key. A gold function is printed above it: press f first, then the key. A blue function is printed on the front slope below it: press g first, then the key.

Press the prefix, release it, then press the function key, one key at a time. For example g√xyˣ is the square root, and f4 sets four decimals. ON cancels a prefix you pressed by mistake.

After pressing f: the f indicator lights. The display shows:  0.00 /  0.00 /  0.00 /  0.00.
After pressing f: the f indicator lights.
After pressing g: the g indicator lights. The display shows:  0.00 /  0.00 /  0.00 /  0.00.
After pressing g: the g indicator lights.

1.4Your first calculation#

To add 3 and 4, key in 3, press ENTER to tell the calculator the number is finished, key in 4, then press +. The answer appears at once. There is no equals key.

Example 1.1

Add 3 and 4

  1. Key in 3, press ENTER, key in 4 and press +.

    3ENTER4+
Result of the example "Add 3 and 4" The display shows:  0.00 /  0.00 /  0.00 /  7.00.
You should see7.00
What happens to the stack in 3 ENTER 4 +.

1.5Clear a mistake#

There is no back arrow. CLx (CLx) clears the number in X. If you are in the middle of typing a number, CLx clears what you typed so far, and you can type it again.

Example 1.2

Clear a wrong number and carry on

  1. Key in 5 and ENTER, key in 7, clear it with CLx, key in 2 and press +.

    5ENTER7CLx2+
Result of the example "Clear a wrong number and carry on" The display shows:  0.00 /  0.00 /  0.00 /  7.00.
You should seeThe 7 was cleared, so the sum is 5 + 2 = 7.00.

1.6Type with a laptop keyboard#

On a computer or Chromebook you can type instead of tapping. Digits, the point, + − * / and Enter work as you would expect. Backspace and Escape clear X, and ^ is yˣ. Capital letters press the five financial keys.

Computer keyCalculator key
0 to 9, .Digits and decimal point
+ - * /+ − × ÷
EnterENTER
Backspace, Escape, DeleteCLx
^yˣ
%%
ff (gold prefix)
gg (blue prefix)
sx⇄y (x⇄y)
rR↓ (R↓)
cCHS (CHS)
eEEX (EEX)
Nn
Ii
VPV
PPMT
FFV

See also Type with your computer keyboard

HP 12C is a trademark of HP Inc.. Trident Calculator is an independent product by South View Studios and is not affiliated with, sponsored by or endorsed by HP. The name is used only to describe the kind of calculator this model resembles; Trident's names, keys, display, fonts and software are its own clean-room design.