Mitsubishi Electric MELSEC FX Series - Page 478

7 Applied Instructions
7.12 Floating Point
476
FXCPU Structured Programming Manual
(Basic & Applied Instruction)
Function and operation explanation
1. 32-bit operation (DESUB, DESUBP)
The binary floating decimal point data in the device specified by are subtracted from the device specified
by , and the result is transferred to the device specified by in binary floating decimal point.
When constants (K, H) are specified in the device specified by or in the device specified by , the
values are automatically converted and handled as binary floating decimal point.
Cautions
1) When the same devices are specified, the same device numbers can be specified in and and
. In this case, when the continuous execution type instruction (DESUB) is used, it must be noted that
the subtraction result changes in every operation cycle.
2) When handling 32-bit data in structured program, you cannot specify 16-bit device directly unlike the
simple project. When handling 32-bit data, please use the label.
However, the 32-bit counter is a 32-bit long device, and can be specified directly.
When specifying the device, use the global label.
3) The instruction is provided in the FX
3G PLC Ver. 1.10 or later.
4) Applicable devices are limited.
S1: FX
3U, FX3UC and FX3G PLCs only are applicable.
S2: FX
3U, FX3UC PLCs only are applicable.
Command input
DESUB
EN
s1
s2
ENO
d
[ +1, ] - [ +1, ] → [ +1, ]
Binary floating
decimal point
Binary floating
decimal point
Binary floating
decimal point
ds1 s2s1 s2 d
Label 1
*1
Label 2
*2
Label 3
*3
*1. To define the device for storing binary floating decimal point data to be subtracted.
*2. To define the device for storing binary floating decimal point data to be subtracted.
*3. To define the device for storing the subtracted binary floating decimal point data.
Command input
DESUB
EN
s1
s2
ENO
d
[ +1, ] - [ K2346 ] → [ +1, ]
Binary floating
decimal point
Automatic conversion
into binary floating
decimal point
Binary floating
decimal point
ds1 s1 d
Label 1
*1
Label 2
*2
Label 3
*3
*1. To define the device for storing binary floating decimal point data to be subtracted.
*2. To define the device for storing binary floating decimal point data to be subtracted.
*3. To define the device for storing the subtracted binary floating decimal point data.