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Section 4: Programming 269
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Press
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Comment
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4000
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STO 1
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Initial downpayment
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STO 2
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($4000).
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1.005
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STO 3
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Monthly inflation factor
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(1.005).
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2000
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STO 4
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Initial savings
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STO 5
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($2000).
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185
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STO 6
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Monthly savings
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($185).
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1.01
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STO 7
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Monthly interest factor
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(1.01).
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Note that the initial downpayment is stored.in both R1 and R2. This is because
in our program r1 will remain the same as the initial value but R2 will contain
the downpayment in successive months. We can at will reset R2 to the initial value saved in
R1 and start over again. The same reasoning holds for R4 and R5 containing
the initial savings.
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One final word before we actually start our program. Normal procedure is to write the entire program
sequence, enter it, and then test it. For the sake of greater understanding, we will write one label
at a time and obtain the answers for that segment of the problem as we go along.
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Programming Label A : Monthly Total Downpayment
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1.
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Switch to W/PRGM.
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2.
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Press fPRGM to clear memory.
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3.
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Key in the sequence of steps below.
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KEY ENTRY
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CODE SHOWN
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COMMENTS
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LBL
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23
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A
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11
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RCL 2
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34 02
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Dnpmt
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RCL 3
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34 03
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Inflation factor
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×
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71
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STO 2
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33 02
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New dnpmt
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RTN
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24
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KEY ENTRY
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CODE SHOWN
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Dnpmt × 1.005 = New Dnpmt
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