327
BCD Calculation Instructions
Section 5-21
5-21-11 SQUARE ROOT – ROOT(72)
Limitations
DM 6144 to DM 6655 cannot be used for R.
Description
When the execution condition is OFF, ROOT(72) is not executed. When the
execution condition is ON, ROOT(72) computes the square root of the eight-
digit content of Sq and Sq+1 and places the result in R. The fractional portion
is truncated.
Flags
ER:
Sq is not BCD.
Indirectly addressed EM/DM word is non-existent.
(Content of
*
EM/
*
DM word is not BCD, or the EM/DM area boundary
has been exceeded.)
EQ:
ON when the result is 0.
Example
The following example shows how to take the square root of an eight digit
number. The result is a four-digit number, with the remainder rounded off. and
then round the result.
In this example,
√
63250561 = 7953.0221..., which is rounded off to 7953.
Sq
:
First source word (BCD)
IR, SR, AR, DM, EM, HR, TIM/CNT, LR
R
:
Result word
IR, SR, AR, DM, EM, HR, LR
Ladder Symbols
Operand Data Areas
ROOT(72)
Sq
R
@ROOT(72)
Sq
R
R
Sq+1
Sq
00000
@ROOT(72)
DM 0000
001
DM 0001
DM 0000
6
3
2
5
0
5
6
1
63,250,561 = 7953.0221
001
7
9
5
3
Address Instruction
Operands
00000
LD
00000
00001
@ROOT(72)
DM
0000
001
(The remainder is rounded off.)
