HP HP-67 User manual

Meet the HP-67*
Congratulations!
With your purchase of the HP-67 Programmable Pocket
Calculator, you have acquired a truly versatile and unique
calculating instrument. Using the Hewlett-Packard RPN logic
system that slices with ease through the most difficult
equations, the HP-67 is without parallel.
As a personal programmable calculator. The HP-67 is so
easy to program and use that it requires no prior programming
experience or knowledge of arcane programming languages.
Yet even the most sophisticated computer experts marvel at
the programming features of the HP-67:
Magnetic cards that record data or programs.
26 data storage registers.
224 program memory steps (expandable to 999**)
Three levels of subroutines, four flags, 20 easily-accessed
program labels.
Indirect addressing using the “I” register.
*Excerpt from the original HP manual
**Added in this emulator!

Topics
In the following pages, we will cover a few topics to get you
started with this emulation of the original HP-67 calculator:
Keyboard layout.
Manual problem solving.
Running programs.
Creating your own programs.
Printing your program listings!
Creating charts!
Instructions on using the built-in program and chart cards.
Keyboard Layout
Each key on the keyboard can have up to three sub-functions
depending on which shift-key is chosen first. The functions
are colored the same as the shift-key: !, !, or !.
For example, this key has three possible shifted functions:!
Black: 1/x, Yellow: SIN, Blue: SIN-1

Manual problem solving
To get the feel of your HP-67, try a few simple calculations.
First, make sure the slider switches at the top are as follows:
(tap them to change their current setting if needed)
!!
!
To solve: 5 + 6 = 11 , press:!
!!!!
You should see 11.00 in your display. This method of
entering calculations, where the numbers are separated with
the ENTER key and the function is selected last, is called
Reverse Polish Notation (RPN), or Postfix entry. It seems a
little odd the first time, but it allows you to enter calculations
without parentheses. For example, if you wanted to divide the
above total by 4, you would simply press 4, then the divide
key:!
!!
You should see 2.75 now in your display. Intermediate
results are stored automatically when you key in new
numbers. This is how you string calculations together.

The value currently displayed is automatically stored as X, it
is always visible. The value that was previously in X is stored
as Y. Functions such as !swap the two values. Press
this:
! ! !, You should see 4.
Now press: !!, You should see 8.00
repeat the above two key and you’ll see 4.00
Some functions, such as Y to the power of X , or !
depend on the numbers being entered as Y ENTER X, then
entering the function !!. If you find you have
entered numbers in reverse, then simply swap them using the
!function. When you select a function, the letters X
and/or Y may appear in the function label - this reminds you
how the function uses the values X and Y.
Negative Numbers
To key in a negative number, press the keys for the number,
then press CHS (change sign). The number, preceded by a
minus (–) sign, will appear in the display. Pressing CHS
again makes it positive again.

Chain Calculations
When you are solving a problem such as:!
(3 x 5) / (3 + 4)
You proceed from inside the parentheses and work your way
out left to right. Intermediate results are displayed and kept as
you go. For the above problem, proceed as follows:
3ENTER 5, then press ×- result 15.00
3ENTER 4, then press +- result 7.00
Finally, press ÷- final result 2.14
As you can see, each sub-result is “stacked” when you begin
a new “nENTER n” calculation. You can go as deep as four
levels. If you need to, you can always save intermediate
results in a register for later recall.
Display more digits after decimal
Press DSP (display), followed by the number of places you
want to see.
Try DSP 4now - if you did the above calculation, you will
now see 2.1429 in the display.

Register Storage
In addition to the automatic storage used during calculations,
there are registers you can store your numbers to and recall
them for later use. These registers are: 0 to 9 and A to E.
To store the displayed number in a register, press the STO
key followed by the register name. To recall a number in a
register, press the RCL key followed by the register name.
You can swap all 0-9 registers between the P(primary) and S
(secondary) banks (the STO/RCL functions only work on the
registers in the P-bank.) Use the !function under the
(F, CHS) key to swap banks. You can keep up to 20 numbers
stored this way - 10 in each bank. (See Charts below).
Running Programs
Use the “Load Card” button to open a program book. The
book graphic emulates the way the original magnetic cards
looked when stored.
Select the program you want, then press “Open.” An
animation will play of the card loading and the sound of the
“card motor”. This is the actual sound recorded from a real
HP-67. When the card is done loading, it will be displayed in
the card holder area above the A-E keys. Note function key
notes can be stored with a program, allowing you to

remember the functions on the program. Notice some built-in
programs are available such as MOON LANDER.
Instructions for that program are in the appendices). To pause/
resume a running program, press R/S key.
Data and Chart Cards
When you see cards in the “Load Card” dialog, you will see
some built-in chart cards with “_C” extension in their names.
These are special data cards stored as charts. After you load
one of these, the “Open” label will appear over the A
function key. Pressing Awill open the chart graphic.
Data-only Card” cards will have a “_D” extension. Loading a
data card will update all the registers from data on the card
saved when it was created.
Saving Programs
Press the “Save Pgm” button to save the currently loaded
program. You will see another dialog allowing you to enter a
name and any function key note labels you might want
displayed.
More on this when we discuss writing programs.

Saving Data
Press “Save Data” to save data from your storage registers
0-9 (Both S and P banks), A-E, and I. They can be copied to a
“Data Card.” There are two types. Both can be used to save
and restore data. The “Data Card” type simply stores the
registers. The “Chart Card” stores the data but allows you to
specify a chart type to display when the card is loaded and
“Open” is run.
Creating Your Own Programs!
Creating programs is, at the most basic, simply storing the
key strokes you would use to complete a calculation and
assigning the keystrokes to a function key for later execution.
There are also advanced commands that let you loop and
branch according to conditions, pause to display output, etc.
However, to start with, you can create simple programs to
automate keystrokes and work your way up to more complex
programs. Programming can be fun! (and addictive), so be
warned.
There is much more on programming the HP-67 on a few
websites. Links will be provided in the Appendices.
Let’s create a simple program to get your started.
Key Codes

First a word about key codes. When you enter a key sequence
into the calculator while in “W/PRGM” mode, you will see
up to three 2-digit numbers in each instruction line. For
example: 31 25 11.
Each of these is a row/column code that maps to your
keyboard. “31” means row 3 column 1 - which is the “f”
shift-key, and so-forth for “25” and “11”.
The one exception is the digit keys. These will be the actual
value such as ’01’ for the 1digit, ’09’ for the 9digit. Since
there is no row “0”, this doesn’t interfere with the other key
codes, and it makes reading the program a little easier, as
numbers are simply the values you enter. However it takes
one line per digit, so try to store large numeric constants in a
register to keep your programs shorter.
Your Own Program
Now let’s try something a little more involved. To calculate
the surface area of a sphere, the formula A= πd2 can be used,
where:
•Ais the surface area of the sphere,
•dis the diameter of the sphere,
•πis the value of pi, 3.141592654.

Ganymede, one of Jupiter’s 12 moons, has a diameter of 3200
miles. You can use the HP-67 to manually compute the area
of Ganymede. Merely press the following keys in order. For a
3200 mile diameter:
3 2 0 0
X2(g-shift 9 key)
π(h-shift 2 key)
×
The result should be 32169908.78
You calculated the surface area of Ganymede! Now, if you
wanted the surface area of each of Jupiter’s moons, you could
repeat that procedure 67 times, using a different value for the
diameter deach time. An easier and faster method, however,
is to create a program that will calculate the surface area of a
sphere from its diameter, instead of pressing all the keys for
each moon.
Creating the Program. A program is nothing more than the
series of keystrokes you would execute to solve the same
problem manually. Two additional operations, a label and a
return are used to define the beginning and end of the
program.
Entering the Program. To load the keystrokes of the
program into the calculator: