## Using the Wang 600 as a Calculator

All calculations on the Wang 600 are performed on either the display or between one of the main registers 00 through 15 and the display.

### Display Functions

The trigonometric, logarithmic, and root functions (keys on the left-most keypad) are all performed on the current value of the display. No registers are altered by these functions. Some of these functions interpret the display as being either Degrees or Radians, depending on the position of the pushbutton switch "Deg ↔ Rad".
KeyFunction
SINCompute the Sine of the display
SIN-1Compute the ArcSine of the display
COSCompute the Cosine of the display
COS-1Compute the ArcCosine of the display
TANCompute the Tangent of the display
TAN-1Compute the ArcTangent of the display
1/XCompute the Inverse of the display
LOGeXCompute the Natural Logarithm of the display
LOG10XCompute the Base-10 Logarithm of the display
exCompute the Natural Exponent of the display
10xCompute the Base-10 Exponent of the display
X2Compute the Square of the display
INT XTruncate the display to an integer
√XCompute the Square Root of the display
|X|Compute the Absolute value of the display

### Register-Display Functions

General math functions (add, subtract, multiply, divide), and moving data around, are all done between the display and a register.

For convenience, two of the main registers are available directly using the "left" and "right" access keys, located to the left and right, respectively, of the central numeric keypad. These keys have the following functions:
KeyFunction
TOTALMove register value into display, and clear register
STORECopy display value into register
RECALLCopy register value into display
+Add display to register, copy sum back into display
-Subtract display from register, copy difference back into display
×=Multiply register by display, copy product back into display
÷=Divide register by display, copy quotient back into display

The "left" register is register 15, the "right" register is register 14.

The rest of the main registers may be accessed using the same functions, but by using the pushbuttons labeled "T" (TOTAL), "+", "-", "×", "÷", "St" (STORE), and "Re" (RECALL). This is accomplished by depressing one of the pushbuttons, for the desired function, and then pressing one of the keys 00 through 15 to perform that function on the specified register. No action is taken until one of the keys 00 through 15 is pressed, in other words changing the pushbuttons takes no action by itself it only prepares an action for when a key is pressed.

### Calculator Example

As an example, consider converting degrees Fahrenheit into degrees Celsius. The basic formula is:
```C = (F - 32) * 5 / 9
```

Note, the calculator has no concept of precedence or parenthesis, so the calculation must be performed in a deliberate order so that precedence is maintained. The first part to perform is the F - 32. Next, that result is multiplied by 5. Finally, that result is divided by 9. Note, an alternate order is to compute 5 / 9 (and possibly store it someplace more permanent) and then multiply by that pre-computed value. For simplicity in example, the first approach is used.

So, the steps required to convert 70 degrees Fahrenheit into degrees Celsius would be:
KeyDisplay, after pressing key
7+7
0+70
STORE (left)+70.000000000
3+3
2+32
- (left)+38.000000000
5+5
×= (left)+190.00000000
9+9
÷= (left)+21.111111111

So, the answer is that 70 degrees Fahrenheit equals (approximately) 21 degrees Celsius.

### Extended Registers

Extended registers may be accessed using the RECALL and (SHIFT) STORE button (on the right-most keypad). This key expects another key to follow, which is used as the register to access. These registers are numbered by a pair of numbers, for example 01 00. Note, register 00 00 is the same as the register accessed using the 00 key. Likewise, register 00 15 is the same as that of the 15 key. Extended registers start with 01 00 and proceed to 15 15. Note, however, that registers above 15 06 are actually system memory and using those registers may crash the calculator (requiring PRIME to recover). Also, registers 01 00 through 15 06 use the same memory as program steps 1847 through 0000, each register consumes 8 program steps. For example, register 01 00 consumes program steps 1840 through 1847.

Using the extended registers normally requires constructing a special code that is not normally created by keys on the keyboard. This is done using the pushbutton switches labeled "1" through "7", and "8" (or "Sp"). The pushbutton "8" actually adds 8 to the value selected by "1" through "7" (if none of "1" through "7" are depressed, then the value "0" is used). So, to create the code for register 15 06, you would depress pushbuttons "7" and "8", then press the key 06. So, to recall the value of register 15 06, you would press RECALL (not the blue left or right keys, but the green key in the right-most keypad) and then, with pushbuttons "7" and "8" depressed, press the 06 key.

While no math functions may be performed directly on extended registers, there is a way to indirectly access these registers. If the register number is converted to a decimal value, as such register 01 00 would be "16", and that value is stored in one of the main registers, then the INDIR key may be used in conjunction with the normal math functions on main registers to perform that same math function on an extended register. For example, if the value "16" were stored in register 00, then performing a INDIR +00 would add the display to register 01 00 (not register 00 00).

Converting a register number (pair) to a decimal value is done by multiplying the first number by 16 and adding the second. For example, register 15 06 would be 15 * 16 + 6 or 246.