Eaton ELC-PB, Programming Manual

Page: 480 / 728

3 . I n s t r u c t i o n S e t
M N 0 5 0 0 3 0 0 3 E F o r m o r e i n f o r m a t i o n v i s i t : w w w. e a t o n . c o m
3 - 3 11
API Mnemonic Operands Function
127 D ESQR P S, D Floating point Square Root
Bit Devices Word devices Program Steps
Type
OP
X Y M S K H KnX KnY KnM KnS T C D E F
S * * *
D *
DESQR, DESQRP: 9
steps
ELC ELCB ELCM
PB PC/PA/PH PV PB PH/PA
32 16 P 32 16 P 32 16 P 32 16 P 32 16 P
Operands:
S : Source address D : Destination address to store the result
Description:
1. This instruction performs a square root operation on the floating point value of source S and
stores the result at the destination D . All operations are performed in the floating point format
and the result will also be stored in floating point format.
2. If the source S is a constant K or H, the integer value will automatically be converted to binary
floating point to perform the ESQR operation.
3. If the ESQR operation result in D is 0 (zero), the Zero flag M1020= ON.
4. S can only be a positive value. Performing any square root operation on a negative value will
result in an “operation error” and this instruction will not be executed. M1067 and M1068 = ON
and error code “0E1B” will be recorded in D1067.
5. Flags: M1020 (Zero flag), M1067 (Program execution error)
Program Example 1:
When X0= ON, the square root of binary floating point value in (D1, D0) is stored in register (D11,
D10) in binary floating point.
D0 DESQR
X0
D10
(D1, D0) (D11 D10)
,
Binary floating point Binary floating point
Program Example 2
When X2= ON, the square root of K1234 (automatically converted to binary floating point) is stored
in (D11, D10).
K1234 DESQR
X2
D10