=== Stack There are four registers, called X, Y, Z, and T. X is displayed. The enter key copies the number from X to Y. LastX is updated when a function uses up the X register, but not when the stack is lifted. When the stack drops, the T register always remains unchanged. There are two keys to manipulate the stack directly, one of which swaps X with Y, and one of which rotates the entire stack downward. There is a "storage register arithmetic" function, wherein one presses STO, then an arithmetic button, then the target register number. Only R0 through R4 can be used. === Display Asterisk in upper left of display indicates low battery. D.MY is displayed; M.DY is the default BEGIN is displayed; END is the default C for compound is displayed; simple is the default To set a fixed precision format, press f followed by 0-9. To use scientific notation, press f then dot. To temporarily display the full mantissa, press f:PREFIX === Clearing Memory To intentionally clear all memory, hold down - while turning on. CLx clears the X register. f:CLEAR_SIGMA clears R1 to R6 and the stack. f:CLEAR_PRGM clears program memory; must be used when in Program mode f:CLEAR_FIN clears financial registers f:CLEAR_REG clears all data registers plus financial and stack === Simple Interest Store values in n, i, and PV (negative). f:INT puts the 360-day interest in X, the 365-day interest in Z, and puts the negated principal in Y. n is in days. === Fixed Repeated Payments The n/i/PV/PMT/FV keys are used to store values in this mode. To view the existing value, press RCL before pressing the key. The g=shift of n and i multipley and divide by 12, to easily convert yearly values into monthly. Pay attention to sign conventions. Pressing any of the 5 buttons *immediately after* any of the others, without entering a new number first, runs the calculation for that parameter instead of storing a value. This mode can be used for any situation where all payments except the initial and final are the same nominal value. To toggle compound interest mode, press STO EEX. A C will appear. Use g:BEG/g:END to set whether the payments occur at the beginning or end of the period. END is the default; BEGIN is displayed if active. If the first period is of irregular length, enter a noninteger n, which essentially updates the PV with the interest from that first partial period. To calculate amortization, set up as above. Enter the number of payments after which to caculate, and press f:AMORT. This puts the amount applied to interest in X, to principal in Y, and the number in Z. Furthermore, n and PV are updated for the amount of loan remaining *after* this. === Nonuniform Payments The calculator can handle 20 different cash flows. Consecutive identical payments count as only 1. Store the initial investment with g:CF0. This has the side effect of storing 0 in n. Then, g:CFi stores the next payment and advances n. The 20th payment is put in FV. If one of the cash flows happens more than once, store the repeat count with f:Nj after storing the value. The interest rate goes in i. Then f:NPV calculates the NPV and also stores it in PV. After this, if desired, f:IRR calculates the intenral rate of return. It is also stored in the i register. Press any key to terminate the IRR calculation with the current estimate; the NPV is close to 0 if it is close to the real value. If Error 3 results, or you stop the calculation, you cna restart with an estimate by entering it and press RCL g:R/S. Cash flow entries can be recalled with RCL then a number. Use a leading period for the second set of 10. Alternatively, set n to the desired number and use RCL CFj. To access the repeat count, only the second method can be used. Note that in this case, the count should be recalled FIRST, because RCL CFj decrements n. === Bonds Bonds are assumed to have a par value of 100 and a semiannual coupon. To calculate price, enter desired yield to maturity in i and annual coupon rate as percentage in PMT. Enter the purchase date and then the maturity date, and press f:PRICE. The price is in X and stored in PV; the interest accrued since the last interest date is in Y. To calculate yield, enter the purchase price as PV, the coupon rate as a percentage in PMT, the purchase date, and the maturity date. Press f:YTM. The yield is put in X and stored in i. === Depreciation Enter the original cost in PV. Enter the salvage value in FV. Enter the life in years in n. (for declining balance, enter the factor - as a percentage - in i). Then, press one of f:SL for straight line, f:SOYD for sum of year's digits, or f:DB for declining balance. The depreciation is put in X and the remaining depreciable value in Y. === Calendar g:M.DY and g:D.MY set month-day ordering. D.MY is indicated if selected. g:DATE adds a date in Y with a number of days in X, resulting in a date g:delta-DYS subtracts a date in X from a date in Y, resulting in a day count In date result, finaly digit is a day of week (Monday=1) === Percentage The % key simply divides the X register by 100 and then multiplies it by Y. The delta-% subtracts Y from X, divides by Y, and multiplies by 100. The %T key calculates what percentage of Y X is. There is a special case to reuse the value in Y by pressing CLX before the new X value. === Statistics g:SIGMA+ accumulates statistics, taking the value from both the X and Y registers. Y is unchanged; X is replaced with the count. To remove a value or pair, press g:SIGMA- Available statistics are: Mean (x-bar), Std dev (s), linear estimate (x-hat, y-hat), mean of x weighted by y (x-bar w) Statistics registers are used as follows: R1 count of samples R2 sum of X values R3 sum of X values squared R4 sum of Y values R5 sum of Y values squared R6 sum of X*Y values === Programming Programming on the 12c stores keystrokes directly. The location is shown on the left, and the row-column position of the buttons is shown to the right of it. The 0-9 buttons are special cased as a single digit instead of location. The SST key goes forwards, while g:BST goes backwards. To go to a particular line, use g:GTO - dot - number in program mode. The dot is not necessary in run mode. Location 0 does not store anything, but executes a special case of halting execution. There is always a GTO 00 instruction provided at the end of the program, even if it is not shown. Program memory is expanded by taking over registers, starting with .9 and ending at 0. There are two conditional instructions: x