Olivetti Programma 101 - Rounding Techniques; Addition, Subtraction, Multiplication Rounding; Division Quotient Rounding

Rounding Techniques
Following are routines for rounding to the setting of the Decimal Wheel in addition, subtraction
and multiplication. Assume one value is stored in the B register and the second value in the e
register:
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ADDITION SUBTRACTION MULTIPLICATION ___________________________
B  B  B  Transfer first value to A register.
C + C - C x Perform operation.
R - R - R - Subtract complete result from trun cated result.
   Transfer complete result to A register.
R - R - R - Subtract negative remainder from complete result.
A  A  A  Print rourded result.
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Following are techniques for rounding the Quotient in a division problem to the setting of the
Decimal Wheel:
METHOD 1:
Assume the divisor is in register B and the dividend is in register C.
C  Transfer dividend to A register.
B ÷ Divide dividend by divisor.
R  Transfer iemainder to A register.
C + Add dividend to remainder.
R  Transfer decimally correct dividend + remainder to A register.
B ÷ Divide dividend + remainder by divisor.
A  Print rounded Quotient.
This routine requires 7 instructions.
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