Omron SYSMAC C200HS Operation Manual page 225

BCD Calculations
15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 00
1 0
15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 00
0 0
Flags
Example
To represent the floating point values, the rightmost seven digits are used for the
mantissa and the leftmost digit is used for the exponent, as shown below. The
mantissa is expressed as a value less than one, i.e., to seven decimal places.
First word
1 0 0 0 0 1 0 0
exponent (0 to 7)
sign of exponent 0: +
1: –
Second word
0 1 0 0 0 1 0 0
mantissa (leftmost 4 digits)
= 0.1111111 x 10
ER: Dr and Dr+1 contain 0.
Dd, Dd+1, Dr, or Dr+1 is not BCD.
The result is not between 0.1 x 10
Indirectly addressed DM word is non-existent. (Content of *DM word is
not BCD, or the DM area boundary has been exceeded.)
EQ: ON when the result is 0.
The following example shows how to divide two whole four-digit numbers (i.e.,
numbers without fractions) so that a floating-point value can be obtained.
First the original numbers must be placed in floating-point form. Because the
numbers are originally without decimal points, the exponent will be 4 (e.g., 3452
would equal 0.3452 x 10
secutive words for the final division, including the exponent and zeros. Data
movements for Dd and Dd+1 are shown at the right below. Movements for Dr
and Dr+1 are basically the same.The original values to be divided are in DM
0000 and DM 0001. The final division is also shown.
0 1 0 0 0 1
mantissa (leftmost 3 digits)
0 1 0 0 0 1
–2
–7
4
). All of the moves are to place the proper data into con-
Section 5-19
7
and 0.999999 x 10 .
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