Mitsubishi Electric melsec q00ujcpu User Manual page 587

(4)
Replacing the High Performance model QCPU with the Universal model QCPU
(a) Replacing all single-precision floating-point operation instructions with double-precision
floating-point operation instructions
Single-precision floating-point data occupy two points of word device per data.
On the other hand, four points are required per double-precision floating-point data.
Therefore, all device numbers for storing floating-point data need to be reassigned.
Example
1)
Device assignment
Application
Data A
Data B
Data C
Result
2)
Program before replacement
3)
Program after replacement
App - 43
Replacing the floating-point operation [A
data into double precision.)
TableApp.36 Device assignment
Before replacement
Device Data type
D0 to D1
D2 to D3
Floating-point data
(single precision)
D4 to D5
D6 to D7
Figure App.20 Sample program
Figure App.21 Sample program
B+C] (Changing all floating-point
After replacement
Application Device
Data A D0 to D3
Data B D4 to D7
Data C D8 to D11
Result D12 to D15
Data type
Floating-point data
(double precision)
Operation is performed using
double-precision floating-point
data.